Dictionary of Ecology and Environmental Science.doc converted

Dictionary of Ecology and Environmental Science Dr. Md. Abdul Ahad Professor, Dept. Of Entomology Hajee Mohammad Danesh Science & Technology University,Dinajpur A.S.M Anas Ferdous Student, Department Of Biomedical Engineering Bangladesh Univeristy Of Engineering & Technology EditionFirst Edition-November 2019 CopyrightAll Rights Reserved By Writer PublisherHimachal Publication Bishal Book Complex Banglabazar, Dhaka Price-150 Tk Dedicated To Father Of The Nation Sheikh Mujibur Rahman Preface Ecology and Environmental Science is two complexes, modern and new subjects. These two subjects are directly and indirectly related and also related with the Limnology. Terminology helps to understand a subject clearly and easily. If one wishes to study and easy understand any subject it is very necessary to know the basic term of that subject. But terminological book of these subjects even text books are limited in our country and even in the foreign countries. Glossary terms are also absent in most text book, even inadequate in the internet. Thinking on the above, this book is written. The terms are collected from different Encyclopedia, Scientific dictionary, different text books, internet etc. and have been carefully complied and edited. Each entry in this book has been defined with the utmost correctness, completeness, and reasonable style. Some terms are explained quite briefly, other at some length. Bold headwords provide quick and easy access to 2136 terms (50046 words). Besides these the Ecology and Environmental science; this book will also provide information to the students and professionals person of Biodiversity, Limnology, Crop science, and Meteorology, Biology and Agriculture at all levels with a handy, and reliable source and may achieves its purpose. A Abiotic: Nonliving components of an ecosystem including soil, water, air, light, nutrients and the like. Abundance: The total number of individuals, or biomass of a specie present in a specified area. Abyssal zone: A zone of the ocean depths between 4,000 to 6,000 m; in other words it is the layer from 4000 to 6000 m depth of the oceans. Abyssal: Relating to the bottom waters of oceans usually below 1000 m. Accelerated erosion: Loss of soil due to wind or water in land. Accelerated extinction: Elimination of species due to human activities such as habitat destruction, commercial hunting, sport hunting and pollution. Accidental species: The species that occur with a low degree of fidelity in a community type. Acclimate: To change phenotypically in a new environment. An individual acclimates and adaptation occurs over many generations. Acclimation: Physiological adjustment to change or other capacity to perform a function in a particular environmental factor, such as temperature or salinity. Acclimatization: Changes or differences in a physiological state that appear after exposure to different natural environments. Acid mine drainage: Sulfuric acid that drains from mines, especially abandoned underground coal mines in the East (Appalachia). This sulfuric acid is created by the chemical reaction between oxygen, water and iron sulfides in coal and surrounding rocks. Acid rain (Acid precipitation):: Precipitation (rain or snow) with an extremely low PH; brought about by a combination of water vapor in the atmosphere with hydrogen sulfide and nitrogen oxides from fossil fuel and interact with water vapor to produce dilute sulfuric and nitric acid. Active solar: Capturing and storage of the sun’s energy through special collection devices (solar panels) that absorb heat and transfer it to air, water, or some other medium, which is then pumped to a storage site (usually a water tank) for later use. Active temperature range: Range of body temperatures over which ectotherms carry out their daily activities. Active transport: Movement of ions and molecules across a cell membrane against a concentration gradient involving an expenditure of energy. In other words it is a movement of the ion or molecule is in a direction opposite to direction taken under simple diffusion. Actual evapotranspiration (AET): The amount of water lost from an ecosystem to the atmosphere due to a combination of evaporation by plants. Actual risk: An accurate measure of the hazard created by a certain technology or action. Acute effects: In general the effect that occur shortly after exposure to toxic agents. Its opposite phrase is chronic effect. Acute toxicity: A toxicity in which a single exposure (dose) or ingestion is poisonous to an animal; and poisoning generally caused by short-term exposure to high levels of one or more agents. Symptoms appear soon after exposure. Adaptation: Evolutionary change that makes an organism functions (behavioral, morphological, and physiological) better in a given environment, which improves an organism's ability to survive and successfully reproduce under prevailing environment conditions. The term is also applied to the anatomical, physiological, or behavioral characteristics produced by this process. Adaptive- It is a radiation from a common ancestor. In other words it is an evolution of divergent forms adapted to distinct ways of life. Adaptive radiation: Evolutionary diversification of species derived from a common ancestor into a variety of ecological roles. Adaptive zone: A particular type of environment requiring unique adaptation. Species in different adaptive zones usually differ by major morphological or physiological characteristics. Additive genetic variance: The degree of phenotypic variation in the population caused by genetic variation, which provided that the heterozygote has a phenotype intermediate between those of the two homozygotes. Adhesion-adapted: A term applied to seeds with hooks, spines, or barbs that disperse by attaching to passing animals. Adiabatic lapse rate: Cooling of rising air without external source of energy for expansion. Advanced industrial society: Post-World war II industrial society characterized by great rises is production and consumption, increased energy demand, and a shift toward synthesis and nonrenewable resources. Aeolian: Related to wind; produced or blown by the wind. Aerobic: Living or occurring only in the presence of free uncombined molecular oxygen, either as a gas in the atmosphere or dissolved in water. Aestivation: Dormancy in animals through a drought or a dry season. Age distribution: The ratio or distribution of individuals among each age group (prereproductive, reproductive, and post reproductive) in a population; often called age structure. The age distribution of a population reflects its history of survival, reproduction, and potential for future growth. Population ecologists can tell a great deal about a population just by studying its age distribution. Age distribution indicates periods of successful reproduction, periods of high and low survival, and whether the older individuals in a population are replacing themselves or if the population is declining. Age of fossils: Age of fossils is determined by determining the age of rocks. Rocks have been found to contain certain radioactive elements, which loss their radioactivities and change to other non-radioactive isotopes at a fixed rate for a definite time. Agents synthetic theory of evolution: Agents synthetic theory of evolution are- i) Natural selection ii) Hybridization or migration or gene flow iii) Mutation iv) Genetic drift (drift) or pure chance and v) Recombination. Age-specific fertility rate: Number of live births per 1000 women of a specific age group. Aggrading: Gradually increasing in structure or biomass. Aggregate dispersion: Distribution of individuals in a clumped or aggregate pattern of dispersion (such as herds, coveys, or schools) Aggregative response: Reaction in which consumers spend most of the time in foods patches with the greatest density of prey. Aggressive mimicry: Resemblance of a predator or parasite to a harmless species to in order not to alert potential prey or hosts. Agricultural land conversion: Transformation of farmland to other purposes such as highways, airports, and the like. Agricultural society: A group of people living in villages or towns and relying on domestic animals and crops grown in nearby fields. It is characterized by specialization of works roles. Agro ecosystem Pest Management (AIM): In broad meaning IPM is concern with the control of all pest of a crop, not only insect but also mites, nematodes, rodents, birds and other vertebrate, plant diseases, and weeds. It is still substitutes of the grower’s culture of the crops. The multitude of decisions a grower must make in successfully raising of a crop has been designated “Agro Ecosystem Pest Management”. Agrotis tenuis: Experiments have shown that the grass, Agrotis plants growing on the polluted soils (lead mine soil) are resistant to heavy metal poisoning (1% Lead and 0.3% Zinc). On the other hand, other Agrotis plants growing in an unpolluted habitat (normal soil) have no such resistance. Hybridization between tolerant and non-tolerant population of Agrotis plant produces fertile offsprings. So, it is not a new species, as it is not reproductively isolated. Raven et al. (1980) confirmed that resistant to heavy metal poisoning Agrotis plant and nonresistant Agrotis plant are races only. A-horizon: Soil layer consisting of a mixture of mineral materials, such as clay, silt, and sand. It is characterized by maximum accumulation of organic matter and biological activity. Albedo: Percentage of light reflected by an object as in the extent the Earth's surface reflects solar energy. Alfisol: Soil characterized by an accumulation of iron and aluminum in lower or B- horizon. In other words it is a gray-brown podzolic soil of temperature latitudes. Algal bloom: Rapid growth of algae in surface water due to increase in inorganic nutrients either nitrogen or phosphorus. Alien species (or foreign species): Any species introduced into or living in a new habitat. It is also known as an exotic species. Alkaloids: Bitter, nitrogen containing compounds that tend to be poisonous to animals and are important defensive chemicals in many plants. They include caffeine, nicotine, morphine, and strychnine. Allee effect: Positive density dependence, usually found only when the population size becomes quite low. Allee principle of aggregation: A special type of density dependence, first identified by W.C Allee in 1931, in which a degree of aggregation results in optimum population growth and survival. Allele frequency: Commonness of an allele (or a gene) in a population of organism. Allele: One of several alternative forms of a gene. Allelochemics: Study of use of chemical agents by organisms to influence other organisms, most particularly as defenses or as lures. Allelopathy: Direct inhibition of one plant species by another, using noxious or toxic compounds Allen's rule: Trend among homoiotherms forelimbs to become longer, and extremity (such as ears) to become less compact, in warmer climates than in colder ones. Allergen: Substance that producing a pathogenic sensitivity within an organism. Allochthonous: Refers to organic materials not generated within the community or ecosystem. Allochthonous food material is reaching an aquatic community in the form of organic detritus. Allogenic succession: Successional changes that are largely the result of external forces, such as fire, flooding or storms. Allometric equation: Equation of the form y=axb. Allopatric speciation: Speciation from a common ancestor into distinct species resulting from the geographical distribution (different areas) of populations sufficient to prevent cross breeding between them. For example polar bears and lions are allopartic. Allopatric: Description of the condition in which populations or species have non-overlapping geographic ranges. Allopolyploidy: Increase in the number of chromosomes sets in a fertilized egg, which receives two unlike sets of chromosomes. Allozyme: Alternative form of a particular enzyme, which differs structurally but not functionally from other allozymes coded for by the different alleles at the same locus. Alluvial soils: Soils that have been deposited by running water. Alpha (α) Diversity: It refers to the variety of species within a region and measure on the basis of number of species in a region. Alpha particles: Positively charged particles consisting of two protons and two neutrons, emitted from radioactive nuclei. Alpine tundra: Tundra-like conditions found above the tree lines on the high mountains Alpine: Mountainous. Altricial condition: Among birds and mammals of being hatched or born usually blind and too weak to support their own weight. Altricial: Has naked or helpless offspring. Altruism: Altruism means the risking of loss of fitness in an act that will improve the fitness of another individual. It is the sacrifice of one’s own well-being for the benefit of another. In genetic terms, it contributes to the genetic fitness of another while decreasing it’s own fitness. Altruism is completely opposite to the Darwinian theory; as natural selection distinguishes against any animal that feeds or cares for another without reward. Alual: structure in birds consisting of a few feathers on the ‘thumb’ which forms a leading-edge slot that helps to maintain smooth air flow and allows flight at slow speeds. Alveoli: Small sacs in the lungs where exchange of oxygen and carbon dioxide between air and blood occurs. Ambient air quality standard: Maximum permissible concentration of a pollutant in the air around us. Contrast with emissions standard. Ambient: Existing conditions; encompassing on all sides. Amensalism: Relationship between two species in which one is inhibited or harmed by the presence of another but the other are not affected. American jacana: Jacanas (Jacana spinosa) are Pantropical; moorhen like bird that have long toes and are able to walk on floating lily leaves. Several species of jacanas are polyandrous, which is a rare condition in bird that makes jacanas of special interest in the behavioral ecology. Amino acid sequences: The linear arrangement of amino acids in a protein. Amino acid: Small organic molecules containing an-NH2 group and a -COOH group; some 20 different kinds serve as ‘building blocks’ of protein molecules. In the process of making a protein, amino acids hook together chemically, producing a string of amino acids. Ammonite: An extinct relative of the octopus with a flat, spiral shell. Anabolism: Metabolic reactions usually requiring energy provided by ATP in which molecules are linked together to form more complex compounds. Anadromous: Animals that migrate from sea to fresh water are called canadromous. Some marine fishes migrate from sea to river for spawning (breed) in fresh-water, such as salmon -Hilsa hilsa. Anaerobic: Adapted of an organism to environmental conditions in the absence of free oxygen. Androgen: A sex hormone responsible for the development of male secondary sexual characteristics such as body hair and a deep voice. Androgenital syndrome: Production of too much androgen by a female fetus. Anemophilous or Anemophily: Wind pollinated. Aneuploidy: Aneuploidy deviate from a base number by one, two or a few chromosomes such as monosomy (2n-1), nulliosomy (2n-2), triosomy (2n+1), and tetrasomy (2n + 2) and so on. Angelfish: A crescent-shaped cichlid fish (freshwater) of the genus Pterophyllum either P. scalare or P. eimekei, which are commonly kept in home aquariums. It also includes the poster-colored saltwater fishes of the family Chaetodontidae and the subfamily Pomacanthinae. Angle of attack: Angle at which birds intercept air flow or relative wind with their wings in order to generate lift. Annuals: Plants that grow from seed- for example, domestic corn and radishes. Anoles: Members of the lizard genus Anolis Anolis: A genus of about 300 species lizard; they are the principal ground- feeding, insectivorous vertebrates. They found primarily in South America and in the Caribbean Island. Anopheles: The genus of mosquitoes that carries malaria. Antagonism: In toxicology, when two chemical or physical agents (often toxins) counteract each other to produce a lesser response than would be expected if individual effects were added together. Antagonistic behavior: All types of unfriendly response to other organisms ranging from clear attack to clear escape. Anthropocentric: It focuses on human values; considering humanity to be the standard or frame of reference. Anthropogenic or Anthropogenic hazard: A danger created by humans. Anthrosol: Human-created urban soil type, containing an abundance of pulverized concrete, dust, debris, and fill materials Antibiotic: Substance produced by a living organism, which is toxic to organisms of different species. Apatosaurus: A giant herbivorous dinosaur, more commonly known as Brontosaurus. Aposematic: Being conspicuous and serving to warn-for example, when toxic animals advertise their poisonousness by aposematic black and red coloration. Aposematism: Possession of warning coloration; conspicuous markings on animals which are poisonous, distasteful, or possess some unpleasant defensive mechanism. Apostalic selection: Selective predation on the most abundant forms in a population, regardless of their appearance, leading to balanced polymorphism, the stable occurrence of more than one form in a population. Applied ecology: The subject in which ecological theory, principles, and concepts are applied to resource management is known as applied ecology. Aquaculture: Cultivation of fish and other aquatic organisms in freshwater ponds, lakes, irrigation ditches and other bodies of water. Aquifer porous: Underground strata (limestone, sand, or grave) bounded by impervious rock or clay, containing significant quantities of water. Aquifer recharge zone: Region in which water from rain or snow percolates into an aquifer, replenishing the supply of groundwater. Aquifer: Underground stratum of porous material (sandstone) containing water (ground water), which may be withdrawn from wells for human use. Arbuscular mycorrhizal fungi (AMF): Mycorrhizae in which the mycorrhizal fungus produces arbuscules (sites of exchange between plant and fungus), hyphae (fungal filaments), and vesicles (fungal energy storage organs within root cortex cells). Arbuscule: A bush-shaped organ on an endomycorrhizal fungus that acts as a site of material exchange between the fungus and its host plant. Arena: Alternative term for elk. Argillic horizon: A subsoil characterized by an accumulation of clays. Aril: A fleshy covering of some seeds that attracts birds and other vertebrates, which act as dispersers of such seeds. Arms race: Retaliatory relationship between species over evolutionary time. Arthropods: The animal phylum comprised of crustaceans, spiders, mites, centipedes, insects and related forms. It is the largest phyla, containing more than three times the number of all other animal phyla combined. Artificial selection: Selection in which a plant or animal breeder creates a differential reproduction of genotypes by choosing the parents of each generation. Artiodactyla: Mammalian herbivores with hooves and an even number of toes, such as antelopes and deer. Asbestos: One of several naturally occurring silicate fibers. Useful in society as an insulator but deadly to breathe even in small amounts. Causes mesothelioma, asbestosis, and lung cancer. Asbestosis: Lung disease characterized by buildup of scar tissue in the lungs. Caused by inhalation of asbestos. Ascendancy: The tendency for self-organizing, dissipative systems to develop network flows over time. Asexual reproduction: Any form of reproduction, not involving the fusion of gametes, such as budding. Aspect diversity: Variations in the outward appearance of species that live in the same habitat and are eaten by visually hunting predators. Assimilation efficiency: The fraction of light striking plants that actually is used in photosynthesis or the fraction of energy consumed (e.g., ingested) by animals that actually is absorbed from the food. Assimilation: Transformation or incorporation of a substance by organisms; for animals, absorption of food energy from the gut; for plants the uptake of carbon dioxide. Association analysis: Investigation for the extent to which species co-occur Association: Natural unit of vegetation often characterized by a relatively uniform species composition and often dominated by a particular species. Asthma: Lung disorder characterized by constriction and excessive mucus production in the bronchioles, resulting in periodic difficulty in breathing shortness of breath coughing. Usually it is caused by allergy and often aggravated by air pollution. Atmosphere: Layer of air surrounding the earth. Atoll: A circular or semicircular group of low islands and coral reefs encircling a lagoon, generally formed on a submerged mountain called a seamount. Atom: A basic unit of matter consisting of a nucleus of positively charged protons and uncharged neutrons, and an outer cloud of electrons orbiting the nucleus. ATP: Adenosine triphosphate, a phosphorus containing compound that is the ‘energy currency’ of all organisms. Aufwuchs (or periphyton): Community of plants and animals attached to or moving about on submerged surfaces also frequently called periphyton. But the term is more specifically applied to organism that attached to submerged plant stems and leaves. Australopithicines: Upright, small brained relatives of modern human beings of the genus Australopithecus that lived roughly 1-4 million years ago. Autecology: Ecology of individual species in response to environmental conditions. Autochthonous: Refers to photosynthesis or organic matter generated within the community or ecosystem. Autogenic succession: Successinal changes largely determined by internal self generated interactions. Automimicry: Phenomenon by which a set of different individuals of the same species mimic each other. Autotroph: An organism that can synthesize organic molecules using inorganic molecules and energy from either sunlight (photosynthetic autotrophs) or from inorganic molecules, such as hydrogen sulfide (chemosynthetic autotrophs). Autotrophic succession: Succession beginning when p/r>1. Autotrophic: Producing of its own food by an organism (as photosynthetic plants) and production is greater than respiration. Autotrophy: Ability of an organism to produce organic material from inorganic chemicals and some source of energy. Auxins: Plant hormones responsible for stimulating growth. Available water: Capacity of supply of water that are available to plants in a well-drained soil. Average fitness of a population (r): The average fitness of the genotypes in a population weighted by their frequencies. B B –horizon: A subsoil in which materials leached from above, generally from the A horizon accumulate. This horizon may be rich in clay, organic matter, iron, and other materials. Balanced growth: Cell growth in which all cell constituents, such as nitrogen, carbon, and DNA, increase at approximately the same rate. Balanced polymorphism: Maintenance of more than one allele in a population by the selective superiority of the heterozygote over both types of homozygous. Barren: An area with sparse vegetation owing to some physical or chemical property of the soil. Barrier islands: Small, sandy islands off a coast separated from the mainland by lagoons or bays. Barrier reef: A long ridge like reef that parallels to the mainland and is separated from it by a deep lagoon. Basal metabolism: The energy expenditures of an organism that is at rest, fasting, and in a thermally neutral environment. Batesian mimicry: Mimicry of a dangerous (noxious) or distasteful species by a harmless or tasty one. Bathyal: Pertaining to anything, but especially organisms in the deep sea (below the photic or lighted zone and above 4000 m. Bathypelagic zone: A zone within the deep ocean that extends from about 1,000 to 4,000 m. Beach drift: Wave-caused movement of sand along a beach. Behavioral ecology: Study of the relationships between organisms and environment that focuses on the behavior of organisms in their natural habitat. Benthic zone: Lowermost region or bottom of a freshwater lake or aquatic ecosystem. Benthic: Living habitats on the bottom of the ocean, and other aquatic environment such as seas, lakes, or streams, are referred to as benthic. Benthos: Animals and plants that live on the bottom of a lake, a river or the sea. Berman's rule: Populations of homoiotherms living in cooler climates tend to have a larger body size and a smaller surface to volume ratio than related populations living in warmer climates. Beta diversity: Variety of organisms occupying a number of different habitats over a period. Beta particles: Negatively charged particles emitted from nuclei of radioactive elements when a neutron is converted to a proton. Bet-hedging: Evolutionary strategy in which an individual adopts two alternative tactics so as to maximize the probability of survival or reproduction. B-horizon: A stratum of soil characterized by minerals in which organic matter in the A-horizon has been converted by decomposers into inorganic compounds such as silica and clay. Biennial: Plant that requires two years to complete a life cycle with vegetative growth the first year and reproductive growth (flowers and seeds) the second year. Big Bang: Theory of the universe’s formation which states that all matter in the universe was infinitely compressed 15 to 20 billion years ago and then exploded, sending energy and matter out into space. The matter was in the form of subatomic particles, which formed atoms as the universe cooled over millions of years. Bioassay: It means the assessment or primary test of toxic substance on living organism in the control condition (in the laboratory). Biocide: Any chemical that kills living organisms. Biocoenose: Animal and plant communities are combined to one unit, roughly equivalent to “ecosystem”; through a version of more closely comparable to ecosystem is known as biocoenose. The word is widely used in Russian literature. Bioconcentration: Ability of an organism to selectively accumulate certain chemicals, elements, or substances within its body or within certain cells. Biodegradeable: Capable of being quickly decomposed by bacterial action. Biodiversity convention: Biodiversity convention took place on June 5, 1992. Earth summit held at Rio de Janeiro (Brazil). The objectives of the convention are: i) conservation of biological diversity, ii) sustainable use of its components and iii) equitable sharing of the benefits arising out of the utilisation of genetic resources, including by appropriate access to genetic resources and by appropriate transfer relevant technologies, and by appropriate funding. Biodiversity: During past twenty years or so biodiversity has attracted attention of numerous workers accelerating the fauna and flora of the world. It is the basic science. According to US Congress Office of Technology Assessment (1987)-Biodiversity refers to the variety, variability among living organisms and the ecological complexes in which they occur. Diversity can be defined as the number of different items and their relative frequency. Thus, the term encompasses different ecosystems, species, genes and their relative abundance Biogas: A gas containing methane and carbon dioxide. Produced by anaerobic decay or organic matter, especially manure and crop residues. Biogeochemical cycle: Movement of elements or compound or nutrients through living organism and physical portions of the biosphere. Examples include the carbon, nitrogen and phosphorus cycles. Biogeochemistry: The branch of science that focuses on the movement of elements or nutrients through organisms and their environment. It is the study of natural cycles of elements and their movement through biological and geological compartments. Biogeocoenosis: The used in European and Russian literature equivalent to the term ecosystem or biocoenosis together with its abiotic components. The term emphasizes both the biological and geological aspects of the ecosystem. Biogeographic regions: Major areas of the word with biomes determined by the past and present positions of the earth’s major land masses. Biogeography: Biogeography (Gk, bios, life, geo, earth, and grapho, waiting) is the study of the geographic distribution of animals on earth and their causes.. Biological amplification: The tendency for chemicals, especially toxic ones, to become more concentrated in organisms than they are in the environment. Biological clock: Internal physiological mechanism of an organism that controls circadian rhythms and keeps time independent of external events enabling organisms to respond to daily, lunar seasonal or other periodicities. Biological community: All of the organisms that live in a given area; sometimes a more restricted group is designated, such as the ‘bird community’- all of the birds found in a given area. Biological extinction: Disappearance of a species from part or all of its range. Biological magnification: Process by which a chemically stable substance or element (such as pesticides, radioactive materials or heavy metal) become more concentrated in each successive link of the food chain. Also called biomagnifications. Biological oxygen demand: Indicator of pollution caused by an effluent related to the uptake of dissolved oxygen by microorganisms that decompose organic matter present influent. The Biological oxygen demand (BOD) in a laboratory is usually the number of milligrams of oxygen consumed per liter of water in 5 days at 200c. Biological resources: Genetic resources, organisms or parts there of, populations, or any other biotic constituent of ecosystems with actual or potential use for humanity. Biological species: A group of potentially interbreeding populations reproductively isolated from all other populations. Bioluminescence: Production of light by living organisms. Biomass accumulation ratio: The ratio of weight to annual production, usually applied to vegetation. Biomass: Weight of living materials usually expressed as dry weight per unit area or volume. Biome: A major ecological community of plant and animal, such as grassland or desert. Biometrical: An approach predicting evolutionary change based on parent -offspring correlation as a description of inheritance. Biophage: Organisms that feed on living material. Bioregion (Bioregional planning): A territory defined by a combination of biological, social and geographic criteria, rather than genuineness. Generally, a system of related interconnected ecosystems. Biosphere reserve (zones): These are undistributed natural areas for scientific study as well as areas in which conditions of disturbance are under control. They have been set sideway for ecological research and habitat conservation. Zones of Biosphere Reserve are two types such as- i) core zone and ii) buffer zone. The core zone invariably conserved in its original form and therefore to be protected from even non-native exotic plants and animals. Buffer zone is the zone nears the border of the protected area; a region between areas managed for different objectives. Biosphere: That part of the environment that occurs near the surface of the Earth in which living organisms exist. Biota: All of the organisms, including animals plants, fungi, and microorganisms, found in a given area. Biotechnology (bioengineering): It means any technological application to uses biological systems, living organisms, or derivatives there of, to make or modify products of processes for specific use. The service of biochemical processes on an industrial scale, most notably recombinant DNA techniques to make or modify products or processes for specific use. Biotic community: Any assemblage of populations living in a prescribed area or physical habitat; regional diversity compared to very local or alpha diversity. Biotic environment: Biological components of an organism’s surroundings that interact with it, including competitors, predators, parasites and prey. Interactions within a population are sub classified as the social, sexual, and parent-offspring environment. Biotic potential: Maximum reproductive potential of an organism. Biotic: It refers to the living components of an ecosystem. Birth control: Any measure designed to reduce births, including contraception and abortion. Birth defect: An anatomical (structural) or physiological (functional) defect in a newborn. Birthrate: The number of new individuals produced in a population. Generally it is expressed as births per individual or per thousand individuals in the population. Biston betularia: The peppered moth famous, as the subject of studies of natural selection in the field. Black smokers: Hot water spring in deep ocean trenches. It is supported by small ecosystems based on bacteria that derive energy from inorganic chemical reactions. Blennies: A family of small slender, marine fishes that include cleaner mimics and dash- and- slash predators. Bloom the sudden explosive growth of a plankton population. Bloom: Algal bloom. Blue book: UNEP has compiled endangered species of the world under the title, ‘Blue Book’. Blue-green algae: Photosynthesizing bacteria of the group known as cyanobacteria. Blytt-Sernander: Sequence of Holocene climatic events in northern Europe. Bog: Wetland ecosystem characterized by an accumulation of peat acid conditions and dominance of sphagnum moss. Bombardier beetles: Certain beetles of the genus Brachinus (Carabidae) that defend themselves with a chemical spray from the tip of the abdomen. Boreal forest or taiga: Needle leaved evergreen or coniferous forest bordering subploar regions; Northern forests that occupy the area south of freezing tundra. Though dominated by coniferous trees they also contain aspen and birch also called taiga. The boreal forest, or taiga, is a world of wood and water that covers 11% of the earth’s land area. Bottom up regulation: Regulation of a community (or ecosystem tropihic structure) related to increased productivity of the producer trophic level influence of produces on the trophic levels above them in the food web. Bottom-up control: It is a control of a community or ecosystem by a physical or a chemical factor such as temperature or nutrient availability. Bourgeois: Strategy for an animal of fighting in a conflict only when it is in own territory. Bower birds: Perching birds from Australia and New Guinea (Ptilonorhynchidae) the males of some species build elaborate, often decorated structures for courtship displays. Breeder reactor: Fission reactor that produces electricity but nonfissile uranium-238 into fissile plutonium-239, which can be used in other fission reactors. Breeding dispersal: Movement of individuals out of a population prior to initiation of the breeding season. Broad spectrum pesticide (or biocide): Chemical agent effective in controlling a large number of pests. Broken-stick model: A model of relative abundance of species obtained by random division into segments of a line representing the resources of an environment. Bronchitis: Persistent inflammation of bronchi caused by smoking and air pollutions. Symptoms include mucus buildup, chronic, cough and throat irritation. Brood parasites: Animals that lay their eggs in the nests of other species, which then serve as foster parents and raise the young. Cuckoos are the classic example of brood parasites. Brown air cities: Newer and relatively non-industrialized cities whose polluted skies contain photochemical oxidants (especially ozone) and nitrogen oxides, largely from automobiles and power plants. Tend to have dry, sunny climates. Contrast with gray air cities. Brown earth: Fertile brown soil type with a characteristic soil profile. Browse: Part of current leaf of shrubs, woody vines, and trees that are available for animal consumption. Bryophyte: Member of the division in the plant kingdom of non-flowering plants comprising mosses, liverworts and hornworts. Bubonic plague: An extremely serious disease caused by the bacterium Yersina pestis. It is carried from rats to human beings by fleas and when in epidemics it is transmitted directly from person to person. Buffer zone: The zone or regions near the border of the protected area; it is a transition zone between areas managed for different objectives. Buffer zone bears the necessary as well as inevitable human pressure ands also meets the research, education and where possible aesthetic needs of society too. In this zone controlled exploitation of natural resources is possible. Buffer: Chemical solution that resists or dampens change in PH upon addition of acids or bases; also used in population biology to refer to any prey species that tends to dampen the impact of predation on another. Bulk flow: The movement of liquid or gas caused by pressure differences. Bundle sheath: Structure, which surrounds the leaf veins of C4 plants, made up of cells, where fourcarbon acids produced during carbon fixation and are broken down to three-carbon acids and CO2. Bushmaster: Lachesis mutus the largest poisonous snake in the Western Hemisphere. The bushmaster is a pit viper (Crotalinae) a member of the same group that includes the rattlesnake. Butyl: Plastic that is often used as a pond liner, as it is very resistant to sunlight and frost. Buzz pollination: Pollination technique in which the vibrations of a buzzing bee shake dry pollen from anthers on to the bee. C C- horizon: A soil layer composed of largely unaltered parent material, little affected by biological activity and the deepest layer in our soil pit. C3 pathway: The capture of carbon dioxide and its incorporation into a sugar. C3 photosynthesis: The photosynthetic pathway used by most plants and all algae, in which the product of the initial reaction is phosphoglyceric acid (PGA), a three- carbon acid. C3 Plant: Any plant that produces as its first step in photosynthesis a three carbon compound phosphoglyceric acid; common in plants adapted to low temperatures average light conditions and adequate water supply. C4 pathway: The capture of carbon dioxide and its incorporation into a sugar, in which the product is a molecule with four carbon atoms compound such as malic or asparitic acid C4 photosynthesis: In C4 photosynthesis, CO2 is fixed in mesophyll cells by combining it with a phosphoenol pyruvate, (or PEP) to produce a four-carbon acid. Plants using C4 photosynthesis are generally more drought tolerant than plants employing C3 photosynthesis. Cactoblasis cactorum: A small moth that intronduced into Australia and successfully controlled the plague of Opunitia cactus there. Calcicole plants: Plant which is susceptible to aluminum toxicity, acidity, and other factors influenced by the absence of calcium. Calcification: Process of soil formation characterized by accumulation of calcium in lower horizons Calcifuge: Plants with low calcium requirement that can live in soils with PH of 4.0 or less. Caliche alkaline: Often rock like salt deposit on the surface of soil in arid regions; forms at the level where leached Ca salts from the upper soil horizons are precipitated. Caliche layer: A calcium carbonate-rich hardpan soil horizon; the extent of caliche formation can be used to determine the age of desert soils. Caliche: Desert soils age those tend to form a calcium carbonate-rich hardpan horizon. Calorie: Amount of heat needed to raise one gram of water at 10c (usually from 150c to 160c). Calorific value: Energy content of biological materials expressed in calories or kilocalories per gram dry weight. CAM (crassulacean acid metabolism) photosynthesis: A photosynthetic pathway largely limited to succulent plants in arid and semiarid environments, in which carbon fixation takes place at night, when lower temperatures reduce the rate of water loss during CO2 uptake. The resulting four-carbon acids are stored until daylight, when they are broken down into pyruvate and CO2. CAM pathway: The capture of carbon dioxide and its incorporation into a sugar, in which CO2 is taken up during the day and fixed using the C3 pathway at night. CAM stands for crassulacean acid metabolism, from a family of succulent plants, Crassulaceae. Cambrian: Earliest period of geological time from about 570 to 500 million years ago. Algae and many marine invertebrates appeared in this period. Canalization: Production of the same phenotype by several different genotypes. Cancer: Uncontrolled proliferation of cells in human and other living organisms. In humans, it includes more than 100 different types afflicting individuals of all races and ages. Cannibalism: Intraspecfic predation; killing and consumption of one's own kind. Canonical distribution: A particular configuration of the lognormal distribution of species abundance. Canopy: The overlapping, intertwined crowns (tops) of forest trees. In a tropical rain forest, the canopy is normally so dense as to make the interior of the forest quite dark, and an entire distinct biota occupies the canopy. Capillary action: Ascent of water to a short distance through a very narrow tubes or spaces. Capillary water: That portion of water in the soil that held by capillary forces between soil particles. Capybara: A dog-sized South American rodent (Hydrochaeris hydrochaeris). Carbon cycle: It is a movement of carbon (C) between the atmosphere hydrosphere and biosphere and the transformational (such as photosynthesis and respiration) between its different chemical forms. Carbon fixation: The capture of carbon dioxide and its incorporation into a sugar. Carboniferous: Second period of the upper Paleozoic from about 345 to 280 million years ago. Early amphibians, reptiles, and giant ferns appeared during this period. Carcinogen: A chemical or physical agent or substance that causes cancer to develop often decades after the original exposure. Carnivore: A flesh eater (any animal) that attacks and eats other living animals (scavengers are usually not included.). It is approximately synonymous with predator. Carrying capacity (K): Maximum size of a population of a species in a particular ecosystem that can be supported by the resources of the area it occupies. This term has acquired so many meanings, which is almost useless. Cascade hypothesis: Any hypothesis influencing of lower trophic levels in the food web studies. Cassowary: A large, flightless bird of Australia and New Guinea in the genus Casuarius, which is related to the emu and the ostrich. Caste: A structurally and usually functionally distinct group of individuals found in a social insect. They are physically distinctive and engage in specialized behavior within a social unit, such as workers, soldiers, or reproductive. Catabolism: Metabolic breakdown of complex molecules to simpler ones. Catadromous: Refers to fish that feed and grow in fresh water, but return to the sea to spawn e.g. Eel. Catalyst: A substance that accelerates chemical reactions but is not used up in the process. Enzymes are biological catalyst. Also see catalytic converter. Catalytic converter: Device attached to the exhaust system of automobiles and trucks to rid the exhaust gases of harmful pollutants. Catastrophic agents: A term used by Howard and Fiske to describe agents of destruction in which the percentage of destruction is not related to population density. It is synonymous with density-independent factor. Catastrophic extinction: Major episode of extinction involving many taxa occurring suddenly in the fossil record. Category: Each rank or level is a higherarchie classification, is called category. Catena: A connected group of related soils series. Cation exchange capacity: Ability of a soil particle to absorb charged ions. Cation: Part of a dissociated molecule carrying an electrical charge. Cellular respiration: Process by which a cell breaks down glucose and other organic molecules to acquire energy. It is also called oxidative metabolism. Cenozoic era: The major division of geological time stretching from the end of the Mesozoic some 65 million years ago to the present. Center of diversity: Geographic region with high levels of genetic or species diversity Ceratopsians: Large herbivorous dinosaurs with prominent horns, the dinosaur equivalent of rhinos. Chamaephyte: Perennial shoots or buds on the surface of the ground to about 25 cm above the surface. Chaos: Unpredictability. Chaparral: A vegetation type characteristic of Mediterranean climates that is dominated by shrubs with thick, small leaves. It is a fire dependent ecosystem, which is replaced by other vegetation types Character convergence: Evolution of similar appearance or behavior in an unrelated species. Character convergence: Evolution of similar appearance or behavior in unrelated species for the purpose of facilitating direct interaction between individuals; also called social mimicry. Character displacement: Changes in the physical characteristics of a species (or population) as a consequence of natural selection for reduced interspecific competition; whereby two species are more different from each other and are sympatric than where they are allopatric. Character divergence: Evolution of differences between similar species occurring in the same areas, caused by the selective effective effects of competition. Characteristics diversity: The pattern of distribution and abundance of populations, species, and habitats under conditions where humanity influence ion the ecosystem is no greater that that of any other biotic factor. Checkerboard: A distribution pattern, in which various localities (analogous 10 squares on a checkerboard) have one or two closely related species. Checkerspot butterflies: A group of belong to the family Nymphalidae, subfamily Nymphalinae, and the tribe Melitaeini. These butterflies are small to medium sized, usually with a black, white, and orange checkered pattern on the wings. Chelation: A complex formation of organic matter with metal ions. For example chlorophyll is a chelate compound in which the metal ion is magnesium (Mg). Chemical defenses: Toxic or repellent chemicals used by an organism to discourage predators. Chemical potential: Energy required converting water from some state- for example, as present in soil in air, or in a leaf- to a reference state, such as pure liquid water under 1 atm and at 200c. Chemoautotroph: An organism that oxidizes inorganic compounds (often hydrogen sulfide) to obtain energy for synthesis of organic compounds; e.g., sulfur bacteria. Chemosynthetic: Refers to autotrophs that use inorganic molecules as a source of carbon and energy. Chernozem: A fertile, deep, black soil with a characteristic soil profile through which percolation is incomplete; mollisol. Chilling tolerance: Ability of a plant to carry on photosynthesis within a range of 50 to 100c. Chlorinated hydrocarbons: A synthetic organic insecticide containing chlorine. They tend to be persistent and to move around in the environment. They often accumulate in fatty tissues of organisms that feed high on food chains. So, it is very harmful to human. Chlorofluorocarbons (CFCs): Chemicals (fluorocarbons), which are responsible for the hole in the ozone layer and contribute to the green-house effect. Chohort: A group of individuals of the same age. Chronic bronchitis: Persistent inflammation of the bronchi due to pollutants in ambient air and tobacco smoke, which is characterized by persistent cough. Chronic effects: In general, the delayed health results of toxic agents for example, emphysema, bronchitis and cancer. Its opposite expression is ‘acute effects’. Chronic obstructive lung disease: Any one of several lung diseases characterized by obstruction of breathing. Includes emphysema, bronchitis, and diseases with symptoms of both of these. Chronic toxicity: In which repeated exposure to small doses over a long period causes poisoning.. Symptoms appear long after exposure. Examples: emphysema and cancer. Cichlid fishes: Freshwater fishes of the family Cichlidae, which includes angelfishes, mouthbreeders, and Jack Dempseys. A large number of species of cichlids live in each of the great lakes of East Africa, occupying a great variety of niche. Circadian rhythm: Ability of an organism to time and repeat functions (physiological or behavioral) of approximately 24 hour in duration even in the absence of conspicuous environmental cues such as daylight. CITES: The Washington Convention on International Trade in Endangered Species of Wild fauna and flora. The convention seeks to provide protection for certain species (e.g. Peregrine) against over use through international trade. Class: In taxonomy, a category just beneath the phylum and above the order, a group of related, similar orders. Cleaner wrasses: Cleaner wrasses are Indo-Pacific fishes of the genus Labroides of the family Labridae, which survive by eating parasites and dead tissues of other fishes that permits them to be ‘cleaned’. Cleaning symbiosis: A mutualistic relationship in which one species benefits from having parasites removed by a cleaning species, which gains a food resource. Clear cutting: Removal of all trees from a forested area. Cleistogamy: Self pollination within a flower that does not open. Climate diagram: A standardized form of representing average patterns of variation in temperature and precipitation that identifies several ecologically important climatic factors such as relatively moist period and periods of drought. Climate diagrams were developed by Heinrich Walter (1985) as a tool to explore the relationship between the distribution of terrestrial vegetation and climate. It summarizes a great deal of useful climatic information, including seasonal variation in temperature and precipitation, the length and intensity of wet and dry seasons, and the portion of the year during which average minimum temperature is above and below 00C. Climate space: The set of environmental conditions, in which an animal can maintain a steady-state temperature that is between its lethal limits. Climate: The average weather conditions-temperature, solar radiation, precipitation, and humidity. Climatic climax: Stable seral stage in equilibrium determined by the general climate of the region. Climax community or ecosystem: A community that occurs late in succession whose populations remains stable until disrupted by disturbance. Climax community: The most stable community on a given soil under a given set of climatic conditions; the end of a successional sequence. Climax: The term introduced by F.E. Clementas in 1916, representing stable end or final community of succession that is capable of self perpetuation in the absence of major disturbance. Climograph: Chart or diagram describing a locality based major climatic factor (the annual cycle of temperature and precipitation) is plotted against another. Cline: Change in population characteristics over a geographic area, usually related to a corresponding environmental rainfall. Clone: A group of genetically identical individuals resulting from asexual reproduction from a single ancestor parent. Closed system: A system that can exchange energy, but does not exchange matter, with the surrounding environment. Example: the earth. Contrast with open system. Closed-community concept: The idea popularized by F. C. Elements, that communities are distinctive associations of highly interdependent species. Clumped distribution: A pattern of distribution in a population in which individuals have a much higher probability of being found in some areas than in others; in other words, individuals are aggregated rather than dispersed. Clutch size: The number of eggs lay by a bird, a reptile, an amphibian, or a fish. This term is also sometimes applied to the number of seeds produced by a plant. Co-adaptation: Evolution of characteristics of two or more species to their mutual advantage. Coal gasification: Production of combustible organic gases (mostly methane) by applying heat and steam to coal in an oxygen-enriched environment. Carried out in surface vessels or in situ. Coal liquefaction: Production of synthetic oil from coal. Coarse grained environment: An environment, in which resources occur in patches sufficiently large with respect to an organism's activities that it can select among them. Coarse grained: Qualities, aspects, or characteristics of an environment with respect to the activities of organisms involved. It is a habitat or landscape patch in which the vagility of a given animal species is low relative to the size of the patch. Coastal wetlands: Wet or flooded regions along coastlines, including mangrove swamps, salt marshes, bays, and lagoons. Its opposite phrase is inland wetlands. Coelacanths: Latimeria chalumnae (Class- Osthichthyes, Subclass- Sarcopteryggi, Order- Crosspteryii, Suborder- Coelcanthini) is believed to be the ancestors of the amphibians. It occurs in the fossil record from the late Paleozoic (550-260 millions year ago) to the Mesozoic (260-130 million years ago). Since none occurred in the last 70 million years of the fossil record. So, it is believed that they had become extinct. But in 1939 more than 30 specimen of Latimeria chalumnae (about 5 feet long) is caught from South Africa. They are being intensively studied and found that it is the Mesozoic fish of their kinds. Co-evolution structured guild: A guild whose members have body sizes determined by coevolution. Co-evolution: It is a type of community evolution (i.e., evolutionary interactions among organisms in which exchange of genetic information among the kinds is minimal or absent). In other words it is joint evolution of two non-interbreeding species having a close ecological relationship; through reciprocal selective pressures, the evolution of one species in the relationship is partially dependent on the evolution of the other. The effect of a predator on the evolution of a prey species, and vice versa is an example. Co-evolutionary: It describes population interaction that involves two species affection each other's evolution. Co-existence: Two or more species living together in the same age class, usually with some form of competitive interaction. Cogeneration: Production of two or more forms of useful energy from one process. For example, production of electricity and steam heat from combustion of coal. Cohort life table: A life table based on individuals born (or beginning life in some other way) at the same time. Cohort: A group born at the same time is called a cohort. Coli-form bacterium: Common bacterium found in the intestinal tracts of humans and other species. It is used in water quality analysis to determine the extent of fecal contamination. Collective properties: Summation of the properties of the parts; for example birth rate, which is the sum of individual births within a designated time period. Colonization cycle: The situation in which stream populations are maintained through a dynamic interplay between downstream drift and upstream dispersal. Co-management: The sharing of authority, responsibility, and benefits between government and local communities for the management of natural resources. Combined response: The combined effect of functional and numerical responses by consumers on prey populations; determined by multiplying the number of prey eaten per predator per unit times, the number of predators per unit area, giving the number of prey eaten per unit area. Combined response is generally expressed as a percentage of the total number of prey. Commensalisms: A relationship in which one species get benefits, but neutral or has no benefit to the other. Common law: Body of rules and principles based on judicial precedent rather than legislative enactments. Founded on an innate sense of justice, good conscience, and reason. Flexible and adaptable. Contrast with statutory law. Common property resource management: The management of a specific resource (such as a forest or pasture) by a well-defined group of resource users w authority to regulate its by members and outsiders. Commons: Any resource used in common by many people, such as air, water and grazing land. Communal courtship display: A display of male animals in the same place competing for females. Communication: An action by an animal that creates a response in another, thought to be, on the average, to the advantage of the communicator. Community diversity: Usually the number of different species in a community. Community stability: The speed with which the community, if disturbed, returns to its original state. Community structure: Attributes of a community such as the number of species or the distribution of individuals among species within the community. Community: Includes all the populations (plants and animals) inhabiting of a specific area at the same time. It is an association of interacting specie that living in a particular area; also often defined as all of the organisms living in an area. Comparative advantage: Relative superiority with which a region or state may produce a good service. Comparative method: A method for reconstructing evolutionary processes and a mechanism that involves comparisons of different species or populations in a way that attempts to isolate a particular variable or characteristic of interest; while randomizing the influence of confounding, or confusing, variables on the variable of interest across the species or populations in the study. Compensation depth: Depth in a lake where light penetration is so reduced that oxygen production by photosynthesis balances oxygen consumption by respiration Compensation intensity: Light intensity at which photosynthesis and respiration balance each other so that net production is zero. In aquatic systems usually the depth of light penetration at which oxygen utilized in respiration equals oxygen produced by photosynthesis. Compensation level: In an aquatic community, the depth of light penetration at which the plants are able to balance their respiration by photosynthesis. Compensation point: Depth of water at which respiration and photosynthesis balance each other; the lower limit of the euphotic zone. Competition coefficient: A coefficient expressing the magnitude of the negative effect of individuals of one species on individuals of a second species. Competition: A relationship between two species that is mutually harmful to both populations. It is the use of a limited resource by two or more different individuals, or the interference by one individual with the resource use of others. Competitive exclusion or Competitive exclusion principle: Hypothesis, which states that when two or more species coexist using the same resource, one species must eliminates another as a result of competition. The two species with identical niches cannot coexist indefinitely. In other words the principle stating that no two species can permanently occupy the same ecological niche. Competitive plants: Competitive plants occupy environments where disturbance intensity is low and intensity of stress is also low. Composting: Aerobic decay of organic matter to generate a humans like substance used to supplement soil. Conduction: Conduction is the direct transfer of heat between substances to other substances in physical contact, as occurs when one sits on a stone bench on a cold weathers day. Conductivity: Constant of proportionality of the pathway along which water is flowing, relating the speed of flow to the pressure difference. Congeneric: Belonging to the same genus. Connectance: Ratio of potential links or interactions in a food web to those that actually exist. Conservation biology: Field of science that concerns with the protection (or conservation) and management of biodiversity (or biological resources). Especially it is the diversity of species based on the principles of basic and applied ecology. Conservation easement: Legal mechanism to designate personal property for ecological economic and conservation benefits. Conservation: A strategy to reduce the use of resources, especially through increased efficiency, reuse, recycling and decreased demand. Conspecifics: Members of the same species. Constancy: A measure of the variability of a system. Consumer: Any organism that lives on other organisms either dead or alive. Sc, the term includes all animals- herbivores, carnivores, and decomposers parasitic and decomposer plants; and most microorganisms those life are producers. Continental drift: According to ‘continental drift’ (offered by Alfred Wegner in1912) there was a large single super continent land mass called ‘Pangaea’ in the primitive the earth. This land mass began to break up in the late Permian and over time span it produces several continents. Continental drifts: The continuous slow movement of the continents and oceans as they are carried along on the tectonic plates, which make up to the surface of the globe. Continuum index: Measure of a position of a community on a gradient defined by species composition. Continuum: Gradient of environmental conditions reflection changes in community composition. Contour farming: A soil erosion control technique in which row crops (corn) are planted along the contour lines in sloping or hilly fields rather than up and down the hills. Contraceptive: Any device or chemical substance used to prevent conception. Control or Control group: In scientific experimentation, a group that is untreated and compared with a treated to show what happens in the absence of the factor under investigation (e.g. the files that are treated just like those exposed to DDT in a selection experiment, except that they are not exposed to DDT). Control rods: Special rods c containing neutron-absorbing materials. Inserted into a reactor core to control the rate of fission or to shut down fission reactions. Convection: The process of heat flow or transfer a moving fluid, such as wind or liquid (or flowing water) or gas. Convective heat transfer coefficient: The constant of proportionality relating the speed of heat flow to the difference between body temperature and air temperature. Convergent evolution: Development of similar form or function in unrelated organisms, living in different areas but under similar environmental conditions, such as the shapes of whales and fishes. Co-operation: Generally involves exchanges of resources between individuals or various forms of assistance, such as defense of the group against predators. Coprophagy: Feeding on feces. Coral atolls: It marks the tropical Pacific and Indian Oceans. This is consisting of coral islets that have built up from a submerged Oceanic island and ring a pond. Coral reefs: Colonial groups of cnidarians that secrete an external skeleton of calcium carbonate, usually in a mutualistic relationship with algae Core zone: Core zone forming the study sanctorum. The core zone invariably conserved in its original form and therefore to be protected from even non-native plants and animals. The area may possibly be open strictly so supervise entry by scientists, research workers and conservation authorities. Coriolis Effect: Physical consequences of the law of conservation of angular momentum as a result of the earth's rotations. So, it produces a deflection of winds and water currents to the right to their direction of travel in the Northern Hemisphere and to the left of their direction of travel in the Southern Hemisphere. Corridor: Connection between two patches of landscape habitat. Cosmic radiation: High-energy electromagnetic radiation similar to cosmic rays but originating from periodic solar flare-ups. It is a process of extraordinary ability to penetrate materials, including cement walls. Cosmopolitan: The organism which is widely distributed over the world. Cosmozoic theory: It is the second theory of the origin of life. Some authorities suggest that the primitive biological systems could have evolved in inter cosmological space, and could have been carried to the earth by meteorites This theory is completely unsatisfactory as due to the intense cold, extreme dryness, and the intense radiation of inter solar space, the living spore may not survive. The theory does not explain the origin of life at all, but just changes the view of origin from the earth to some remote and undefined parts of the universe. Counter adaptation: Evolution of characteristics of two or more species to their mutual disadvantage. Counter evolution: Development of traits in a population in response to exploitation, competition, or other detrimental interaction with another population. Countercurrent circulation: Anatomical and physiological arrangement by which heat exchange takes place between outgoing warm arterial blood and cool venous blood returning to the body core. It is important in maintaining temperature homeostasis in many vertebrates. Country of origin of genetic resources: It means the country which possesses those genetic resources in situ conditions. Country providing genetic resources: It means the country providing genetic resources collected from in situ sources, including populations of both wild and domesticated species, or taken from ex situ sources, which may or may not have originated in that country. Crassulacean acid metabolism (CAM): Method of Co2 fixation that conserves water in certain succulent, drought-resistant desert plants. Crepuscular: Animal that actives at dawn or dusk. Cretaceous: The last period of the Mesozoic from about 136 and 65 million years ago when much of the present land area was covered by shallow seas. Evolution of modern birds and fish; appearance of primitive mammals observed of the period. Cretaceous-tertiary boundary: The boundary between the last period of the Mesozoic and the first period of the Cenozoic, some 65 million years ago. The boundary is marked by the destruction of many group organisms including the dinosaurs, thought by some to have been caused by the crash of an asteroid with Earth. Critical habitats: Habitats under special fears are called critical habitats. Critical population size: Population level below which a species cannot successfully reproduce. Critical thermal: Maximum temperature at which animals have no capacity to move and is so reduced that it cannot escape from thermal conditions that will lead to death. Critically Endangered (CR): Species faces very high risk of extinction in the wild in the immediate future. Crocodilians: Crocodiles, alligators, gavials, and their extinct relatives. Crop rotation: Alternating crops in fields to help restore soil fertility and also control pests. Croppers: Browsers or grazers but not animals that eat seeds or fruits that must be sought out in a manner analogous to hunting. Cropping principle: Predation that keeps prey populations low (works to allow increased diversity). Cross resistance: Resistance or immunity to one disease organism resulting from infection by another, usually closely related organism. Cross-fertilization: Sexual reproduction in which the two gametes come from different individuals. Cross-media contamination: The movement of pollution from one medium, such as air, to another, such as water. Crude birth rate: Number of births per 1000 people in a population at the midpoint of the year. Crude death rate: Number of deaths per 1000 people in a population at the midpoint of the year. Crude density: Number of individuals per unit area. Cryogenics: The branch of physics relating to the effects and production of very low temperatures, as applied to living organisms’ preservation in a dormant state by freezing, drying or both. Cryophytes: Buds is buried in the ground on a bulb or rhizome. Crypsis: An aspect of the appearance of organisms whereby they avoid detection by others, usually applied to the prey of visually hunting predators. Cryptic coloration: Coloration of organisms that makes them resembles or blends into their habitat or background. Cuckoo dove: Fruit eating pigeon that lives in the middle story of shaded forest from India to Melanesia. Cultivar: A cultivated variety (genetic strain) of a domesticated crop plant. Cultural control (of pests): Techniques to control pest populations not involving chemical pesticides, environmental controls, or genetic controls. Examples, cultivation to control weeds and manual removal of insects from crops. Cultural diversity: Variety or multiformity of human social structures, behalf systems, and strategies for adapting to situations in different parts of the world. Cultural eutrophication: Over fertilization of freshwater ecosystems by nutrients, mainly nitrogen and phosphorus, from anthropogenic sources. Cyanbacteria: Group of bacteria (blue green algae) that possess chlorophyll ‘a’ and that carry out photosynthesis. Cyberanetics: The science that deals with communication systems and system controls in ecology and the life sciences the study of feedback controls in homeostasis. Cyclic climax: A steady-stage, cyclic sequence of communities, none of which by itself is stable. Cyclic replacement or Cyclic succession: Succession caused by periodic rhythmic disturbances in which the sequence of seral stages in repeated, preventing the development of a climax or stable plant community. Cyclomorphosis: Changing of shape with succeeding generations. Cyclops: A tiny freshwater crustacean. D Daily energy expenditure: Amount of energy needs for a free-living organism over 24 hours. Dark reaction: Group of light independent reactions following the light reactions in photosynthesis (the second part of photosynthesis); adenosine triphoshate (ATP) and nicotinamide adenosine dinucleotied phosphate (NADPH) are used to capture carbon dioxide to produce glucose and other carbohydrates (sugar). Daughter nuclei: Atomic nuclei that are produced during fission of uranium. Day neutral plant: A plant that does not require any particular photoperiod to flower. Death rate: The number of individuals in a population dying during a given time interval divided by the total in the population at the midpoint of the period. Decibel (dB): A unit measures the loudness of sound. Deciduous (of leaves): Shed of leaves of trees during a certain season such as winter in temperate regions and dry seasons in the tropics. Deciduous forest: A forest in which the dominant trees drop leaves before an unfavorable winter conditions or season, temperate deciduous forests are a major biome-type in Eastern North America. Decomposer: An organism that survives by feeding on the wastes of other organisms. In other words organism that obtains energy from breakdown of dead organic matter to more simple substances. Decomposers play a crucial role in nutrient cycles by breaking down complex organic molecules into simpler constituents. Most precisely it refers to bacteria and fungi. Decomposition: Breakdown of complex organic materials into simpler ones; accompanied by the release of carbon dioxide and other inorganic compounds. It is a key process in nutrient cycling. Deductive or Deductive method: In testing hypotheses, reasoning from the specific to the general conclusions. Deep scattering layer: Plankton at depths in the oceans by day as recorded by sonar. Defaunate: To remove all animals form. Deforestation: Destruction of forests by clear cutting. Defuitive host: A host in which a parasite becomes an adult and reaches maturity. Deleterious allele: Allele possession of which (usually in the homozygous state) harms an individual. Deme: Local population or interbreeding group within a larger population. Demographic stochasticity: Random fluctuation (or variations) in population birth and death rates caused by entirely to chance differences by individuals when the environment is practically uniform. Demographic transition: A phenomenon observer in a population industrializing nations. As industrialization proceeds and wealth accumulates, crude birth rate and crude death rate decline, resulting in zero or low population growth. Demographic unit: A population sufficiently isolated from others that its dynamics are independent of migration. Demography: The rate of growth and the age structure of populations, and the processes that determine these properties. Dendrochronology: Dating by tree rings. Denitrifaction: The conversion of nitrate and nitrite to elemental nitrogen (atmospheric nitrogen) by microorganisms Density dependent: Influenced by the size of the population (varying in relation to population density), usually caused by weather-related changes. Density independence (Density independent): Unaffected by population density; regulation of population growth not related to population density. So, changes in population number are independent of population size. Density: The number of individuals in a population per unit area. Density-dependent factor: Biotic factors in the environment, such as disease and competition, are often called density-dependent factors because their effects on populations may be related to, or depend upon, local population density. Density-independent factor: Abiotic factor in the environment, such as floods and extreme temperature, arc often called density-independent factors because their effects on populations may be independent of population density. Dependent variable: A variable, which yields the second of two numbers in an ordered pair (x, y). It is the set of all values taken on by the dependent variable is called the range of the function. Its opposite term is independent variable. Deposit feeder’s: Organisms that ingest grains of sediment and assimilate the bacteria and other microorganisms. Depressurized zone: Aquifer containing superheated, pressurized water and steam trapped by impermeable rock strata and heated by underplaying magma. Desert: An arid biome occupying approximately 20% of the land surface of the earth and with less than 25 centimeters of rainfall per year, where water loss due to evaporation and transpiration by plants exceeds precipitation during most of the year. Desertification: The creation of desert as a result of human activities in arid and semiarid regions from overgrazing deforestation, poor agricultural practices and climate change. Desertification is found today in Africa, the Middle East and the southwestern United States. Deterministic model: mathematical model in which all relationships are fixed and a given impute produces one exact production as an output. Deterministic: Without a concept of probability or measurement uncertainty. Detoxification: Making a substance harmless by reacting it with another chemical, through chemically modifying it, or destroying the molecule by combustion or thermal decomposition. Detritivores: Organisms that feed on nonliving organic matter (decaying organic matter), usually on the remains of plants (such as earthworms). Detritus food chain: Food chain in which the primary producers are not consumed by grazing herbivores, but where dead and decaying plant parts from litter on which decomposer (bacteria and fungi) and detritivores feed, with subsequent transfer of energy thought the detritus food chain. Detritus: Dead or partially decomposed plant and animal matter; nonliving organic matter. Developed country: A convenient term that describes industrialized nations, generally it is characterized by high standard of living low population growth rate, low infant mortality, excessive material consumption, high per capita energy consumption, high per capita income, urban population and low illiteracy. Developmental response: Acquisition of one of several alternative forms by an organism, depending on the environmental conditions under which it grows. Devonian: Period between the Ordovician and the Carboniferous some 405 to 355 million years ago; the age of fish; evolution of early amphibian; appearance of vascular plants, insects, and spiders. Dew point: Temperature at which condensation of water in the atmosphere begins. Diameter breast height (dbh): Diameter of tree measured 4 feet, 6 inches (1.4 m) from ground level. Diapause: A resting state (period of dormancy) of an insect usually seasonal, in which development is ceased, little energy is used and metabolism is greatly decreased. Insects often enter diapauses prior to a period of unfavorable environmental conditions. Didinium: A barrel-shaped predatory protozoon. Differential reproduction: Reproduction of some individuals more frequently than others. Diffuse competition: The sum of weak competitive interactions with species that are ecologically distantly allied. Diffuse-co-evolution: Co-evolution among more than two species, for instance between predators and their prey. Diffusion: Transport of material due to random movement of particles; net movement is from the areas of high concentration to the areas of low concentration. Dimer: A molecule composed of two distinct subunits. Dimictic: Refers to mixing or inversion of a lake twice a year. Dimorphism: Occurrences of two forms of individuals in a population. Dioecious: Plants in which male and female reproductive organs are borne on separate individuals, so that the entire plant may be called male or female. Diplacus: A snapdragon plant that serves as the larval food for some checkerspot butterflies. Diplodocus: A large, Apatosaurus-like dinosaur. Diploid: Having two sets of chromosomes in undifferentiated cells. Direct competition: Exclusion of individuals from resource by aggressive behavior or use of toxins. Directional selection: Selection favoring or leading to an individuals at one extreme of the phenotype trait in the population. Disclimax: Seral stage of succession maintained by anthropogenic (human-generated) disturbance. Disease: Any deviation from normal state of health. Dispersal: Movement away from the place of birth (or origin) to another area, movement of individuals or their seed, larvae, or spores into or out of a population or area. Dispersion: Distribution of organism within a population over an area i.e. the spatial pattern of distribution of individuals in a population over an area. Dissolved oxygen concentration: Measure used as an index of the pollution of lakes because it is a measure of Eutrophication. Distribution: The natural geographic range of an organism or the spatial arrangement of individuals in a local population. In other words the geographic area occupied by a taxonomic group (a species or genus). Disturbance corridor: A linear disturbance through the landscape matrix. Disturbance: A disturbance more broadly as any relatively discrete event that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment. Disuptive selection: A selection in which two extreme phenotypes in the population leave more offspring than the intermediate phenotype, which has lower fitness. Diversity productivity hypothesis: A hypothesis based on the assumption that interspecific differences in the use of resources by plants allow more diverse plant communities to more fully use limiting resources and, thereby, attain greater net primary productivity. Diversity stability hypothesis: A hypothesis based on the assumption that primary productivity in more diverse plant communities is more resistant to and recovers more fully from major perturbations such as drought Diversity: Abundance in number of species in a given location; a measure of the number of different species in an ecosystem. DNA: It denotes deoxyribonucleic acid, the chemical that carries the genetic code in the sequence of the four kinds of subunits (nucleotides) of which it is made. It is a sequencing method for determining the sequence of nucleic acids in DNA molecules. Domesticated or cultivated species: Domus= ‘home’ means species in which the evolutionary process has been influenced by humans to meet their demand. Dominance (ecological): Control within a community over environmental conditions influencing associated species or several species, plant or animal, enforced by number, density or growth form. In genetic it is an ability of an allele to mask the expression of an alternative form of the same gene in a heterozygous condition Dominance diversity curve: Number or percentage of each species plotted in sequence from the most abundant to the least abundant in a defined habitat. It is an expression or graph of species diversity based on species importance. Dominance hierarchy: Orderly ranking of individuals in a group, based on the outcome of aggressive encounters. Dominant population: Possessing ecological dominance in a given community and thereby governing type and also abundance of other species in the community. Donor control: A predator-prey interaction in which the predator does not control the prey population size. Dormant: State of cessation of growth and suspended biological activity during unfavorable condition through which life is maintained. Dose-response curve: Graphical representation of he effects of varying doses of chemical or physical agents. Doubling time: The length of time that takes some measured entity (population) to double in size at a given growth rate. Dove: Strategy of never fighting in a conflict. Drag: Force resulting from the components of pressure and friction. Drift: The active or passive downstream movement of stream organisms. Drosophila: The genus of fruit flies (sometimes called vinegar flies) that are used extensively in genetic research. Drought avoidance: Ability of a plant to escape dry periods by becoming dormant or surviving the period as a seed. Drought resistance: Sum of drought tolerance and drought avoidance. Drought tolerant: Ability of plants to maintain physiological activity in spite of the lack of water or to survive the drying of tissues. Dung flies: Flies that survive as larvae living in decomposing feces, especially Scatophaga stercoraria (Scatophagidae). Dynamic pool model: Optimum yield model using growth, recruitment, mortality and fishing intensity to predict yield. Dystrophic: Refers to a body of water with a high content of humic organic matter, often with high littoral productivity and low plankton productivity, with deeper water depleted of oxygen such as a shallow freshwater lake. E Earth Summit: The international Rio Earth Summit of 1992 set a path for sustainable development in the 21st century. A key element was a treaty to conserve biodiversity. Over 150 countries, signed the Convention of Biological Diversity. Some of the countries have prepared and many more are preparing blueprints to save study and use biodiversity Ecesis: Establishment of the first stage in succession. Ecocline: A geographical gradient of vegetation structure produced by responses of vegetation to environmental gradients of rainfall, temperature, nutrient concentration, and other factors. Ecological (Lindeman) efficiency: Ratio of gross production between trophic levels. Ecological backlashes: Ecological effects of apparently safe activities for examples, the greenhouse effect. Ecological density: Number of individuals per area of available living space or habitat space (that is, the area of habitat that can actually be colonized by that population). Ecological Diversity: Ecological diversity is the complex network of different species present in local ecosystems and the dynamic interplay between them. Measuring ecological diversity is difficult because each of the Earth’s ecosystems merges into the ecosystems around it. Ecological economics: Field of study that attempts to integrate economic capital (gods and services provided by humankind, or the human workforce ) with natural capital (goods and services provided by nature). Ecological efficiency: Percentage of biomass produced by one trophic level that is incorporated into biomass of the next highest trophic level. Ecological equivalents: Organisms that occupy similar ecological niches in different regions of the world. Ecological footprint: The area of productive ecosystems outside a city that is required to support life in the city. Ecological isolation: Avoidance of competition between two species by differences in food, habitat, activity period, or geographical range. Ecological release: Expansion of habitat and resource utilization by population in regions of low species diversity, resulting from reduced interspecific competition. Ecological study unit (ESU): Physical size of the experimental study area, mesocosm, or patch required in order to achieve proper replication. Ecological succession: Sequential appearance of species or communities; process of change and development whereby previous seral stages are replaced by subsequent seral stages until mature (climax) community is established. Ecological time: Duration of interactive process among existing species. Ecologism: Linkage of ecological ideas with energy economics; the environment movement. Ecologist: A person who studies ecology. Ecology: (Greek, oikos, ‘household’ and logos, ‘study of’) Branch of science that deals with interactions and relationships between organisms and the environment. It is the science that trades with the relationship between organisms and their physical and biological environments. Ecomorph: An animal with a characteristic size, shape, color, and modal location in the habitat. Economic depletion: Reduction in the supply of a resource to the point at which it is no longer economically feasible to continue mining, extracting or harvesting it. Economic externality: A cost of manufacturing, road building, or other action that is not taken into account when determining the total cost of production or construction. A cost generally passed on to the general public and taxpayers. Ecophysiology: That branch of ecology concerned with the responses of individual organism to abiotic factors such as temperature, moisture, atmospheric gases, and other factors of the environment. Ecoregion: Classification of major vegetation types or ecosystems developed R.W Bailey in 1976, based on a continuous land area in which the interaction of climate, soil, and topography permit the development of similar types of vegetation Ecosphere (biosphere): All the living organisms of Earth interacting with the physical environment as a whole. Ecosystem approach: Measurement based on ecosystem functions and processes is called ecosystem approach. Ecosystem services: Services provided to humanity by natural ecosystems such as amelioration of weather, control of water flows, maintenance of soils, disposal of wastes, and recycling of nutrients. Ecosystem: The term is first used by A. G. Tansley in 1935. The biological community in an area and all of the abiotic factors influencing that community; here a biotic community and its abiotic environment functions as a system. Ecotone: Zone of transition from one type of community or ecosystem to another for instance, the transition from wood land to grassland. The change along an ecotone involves analogous changes in the structure of vegetation. Ecotype: Subspecies (or race or local populations) adapted to a particular set of environmental conditions. Ectocrine: Chemical secreted into the environment that influences other organisms. Ectomycorrhizae (ECM): An association between a fungus and plant roots, in which the fungus forms a layer around roots and a netlike structure around root cells. Ectotherm: An organism that relies mainly on external sources of energy for regulating body temperature. Ectothermy: Determination of body temperature primarily by external thermal conditions Edaphic climax: Stable plant community equilibrium dependent on soil, topography, and local microclimatic conditions as opposed to the general climate. Edaphic: Relating to soil. Edge effect: Response of organisms in particular environmental conditions created by the edge where two or more communities or ecosystems meet (typically creating an increase in biotic diversity along the edge site). Edge species: Species that inhabit edge or boundary habitats; species that use edges for reproductive and survivorship purposes. Edge: Place or site where two or more vegetation types (structurally different communities or ecosystems) meet, such as the edge of a pond or lake. Effective population: Size of an ideal genetically distinct population that would undergo the same amount of random genetic drift, as the actual population. It is the minimum population size, below which a given species might lose its evolutionary potential. Sometimes it is used to measure the amount of inbreeding in a finite, randomly mating population. Egestion: Elimination of undigested food material. Egyptian vulture: Nephron perconpterus also known as Pharaoh's chicken EIA (Environmental Impact Assessment): A report, based on detailed a study that discloses the environmental consequences of course of action as an aid to decision making. Eighty-nine butterfly: Various species of the genera Callicore and Diaethria (Nymphalidae) that have a pattern on the underside of the hind wings that resembles the number 89. El Nino: A large-scale coupled oceanic-atmospheric system that has major effects on climate worldwide. During an El Nino, the sea surface temperature in the eastern Pacific Ocean is higher that average and barometric pressure is lower. Elaiosome: A structure on the surface of some seeds (tissue on the seed coat) of many plants generally containing shiny oils attractive to ants, which act as dispersers of such seeds. Electrophoresis: An analytical technique involving the separation of molecules in an electrical field. It is a procedure for separating different proteins on the basis of their electric charge. Elfin wood: Low-growing wood found on certain tropical mountains. Emergence theory: A theory that the whole possesses properties not possessed by the individual components. Emergent property: Refers to properties at various levels of organization that cannot be derived from lower-level systems studied in isolation. eMergy: Amount of one type of energy required to develop the same amount of another type; amount of energy already used directly or indirectly to create a service or product. Emigration: One way permanent movement of individuals out of an area. Emissions offset policy: Strategy to control air pollution in areas meeting federal ambient air quality standards, whereby new factories must secure emissions reductions from existing factories to begin operation; thus the overall pollution level does not increase. Emissions standard: The maximum amount of a pollutant permitted to be released from a point source (see definition). Emphysema: A progressive, debilitating lung disease caused by smoking and pollution at work and in the environment. This disease is characterized by gradual breakdown of the alveoli and difficulty catching one’s breath. Emu: Australian flightless bird (Dromiceius novae-hollandiae) related to and almost as large as the ostrich. Endangered (EN): Species faces very high risk of extinction in the wild in the near future. Endemic (species): Animals living with in a restricted geographic region are called endemic or native for that area in other words it is a species which occurs continuously in a given area and found nowhere else. Endorheic: Interior drainage (used of closed basin lakes). Endosymbiotic theory: A view that several of the important components of eukaryotic cells, such as mitochondria, were once free-living organisms. Endotherm: An organism that relies mainly on internal sources of energy for regulating body temperature. Endothermic thermoregulator: An animal usually bird or mammal that uses its metabolism as a primary source of body heat and uses physiological mechanisms to hold its body temperature nearly constant. Endothermy: Regulation of body temperature by internal heat production, which allows maintenance of appreciable difference between body temperature and external temperature. Energy budget: The rate at which an organism takes its energy relative to the rate at which it expends energy. Energy budget gives an indication of the amount of energy available for functions such as reproduction. Energy flow: Concept that food transfer between prey and predator is calorate transfer with energy release, hence s unidirectional flow. Energy pyramid: Pyramid of energy. Energy quality: The amount of useful work acquired from a given form of energy. High quality energy forms are concentrated (e.g. oil and coal); low-quality forms are less concentrated (e.g. solar heat). Energy subsidies: Subsidies from outside the system (such as fertilizer, pesticides, fossil fuels, or irrigation) that enhance growth or rates of reproduction within the system. Energy system: The complete production consumption process for energy resources, including exploration, mining, refining, transportation and waste disposal. Energy: Capacity to do work. Energy is found in many forms such as heat, light, sound, electricity, coal, oil and gasoline. Enthalpy: State of order in a thermodynamic system. Entomophilous: Insect pollinated. Entomophily: Insect pollination. Entrainment: Synchronization of an organism's activity cycle with environmental cycles. Entropy: Physicist’s term describing transformation of matter and energy to a more random and a more disorganized state. It is a measure of disorder. The second law of thermodynamics applied to matter says that all systems proceed to maximum disorder (maximum entropy). Environment: All of the elements in an organism's surroundings that can influence its behavior or survival including other plants and animals and those of its own kind. Environmental control (of pests): Methods designated to alter the abiotic and biotic environment of pests, making it inhospitable or intolerable. Examples include increasing crop diversity, altering time of planting, and altering soil nutrient levels. Environmental gradient: A continuum of conditions ranging between extremes, as the gradation from hot to cold environments. Environmental heterogeneity: The physical or temporal patchiness of the environment. Heterogeneity exists at all scales within natural communication ranging from habitat differences between the top and underside of a leaf, to habitat patches created by tree falls, forest, to the pattern of forest and grasslands within a region. Environmental impact statement (EIS or ES): Document prepared primarily to outline potential impacts of projects supported in part or in their entirety by federal funds. Environmental phase (of the nutrient cycle): Part of the nutrient or biogeochemical cycle, in which the nutrient is deposited or cycling through the environment (air, water and soil). Environmental resistance: Sum total of environmental limiting factors both biotic and abiotic that can potentially reduce population size. Environmental science: The interdisciplinary study of the complex and interconnected issues of population, resources and pollution. Environmental stochaticty: Unpredictable environmental changes, such as bad weather or food failure, that affect some aspect of population growth. Environmental variance: Phenotypic variance among individuals with the same genotype. Environmentalism: Guiding principle of those devoted to the health and sustainability of planet Earth. Enzyme: A protein that serves as a biological catalyst, speeding the rate of a chemical reaction. Eocene period: The second period of the Cenozoic era, about 45 million years ago. Ephemeral: Organisms with a short life cycle (short-lived); lasting only a season or a few days. They persist as seeds during periods of drought, but sprout and produce seeds quickly when moisture is favorable. Epideictic display: Sexual display postulated to serve the purpose of a density-measuring device (a view not generally held by ecologists). Epidemic: Rapid spread of a bacterial or viral disease in a human population. Epifauna: Benthic organisms that live on the surface of a soft sediment or move across the surface of a substrate. Epilimnion: The upper warm and oxygen rich layer of lakes water, which is warmed by the sun and mixed by the wind i.e. the well-lighted surface layer of a lake or other body of water. Epipelagic zone: The warm, well-lighted surface layer of the oceans that extends to a depth of 200 m. Epiphyte: A plant that grows on another plant but is not parasitic. It deriving support but not take nutrients from the plants; such as an orchid and ferns, which live on the branches and trunks of other plants. As they grow on the branches of a tree they begin to trap organic matter, which eventually forms a mat. The nutrient stores in the rain forest canopy are associates with epiphytes. Epizootic: Rapid spread of a bacterial or viral disease in a dense population of animals. Equilibrium isocline: A line on the population graph designating combinations of competing populations, or predator and prey populations, for which the growth rate of one of the populations is zero. Equilibrium model: Any hypothetical or actual representation of a system in which two balancing forces act to maintain stability in the system. Equilibrium species: Species whose population exists in equilibrium with resources and at a stable density. Equilibrium turnover: Rate of change in species composition per unit time when immigration equals extinction. Equilibrium: A state of balance in a system in which opposing factors cancel each other. Equitability: Evenness of distribution of species abundance patterns; maximum equitability is the same number of individuals in all species. Error acceptance criterion: Risk one is willing to take of reaching an incorrect conclusion. Escherichia coli: A bacterium isolated from human feces that has been a key tool for geneticists working on the biochemical mechanisms of heredity. Estivation: A dormant state that some animals enter during the summer (or a period of drought or a dry season), involves a reduction of metabolic rate. Estrus: The stage of the sexual cycle of a female mammal when it is both receptive to intercourse and able to conceive. Estuaries: Estuaries are found wherever rivers meet the sea. Estuarine zones: Coastal wetlands and estuaries. Estuary: Coastal regions such as inlets or mouths of rivers where freshwater and seawater meet and mix and also where tidal action is an important physical regulator and energy subsidy. Ethanol: Grain alcohol, or ethyl alcohol, produced by fermentation of organic matter. Ethanol can be used as a fuel for a variety of vehicles and as a chemical feedstock. Ethology: Study of animal behavior in natural situations. Etiology: The cause or developmental history of a condition. Eukaryotic: Cell that has membranous organelles, notably the nucleus Euphotic or Euphotic zone: Zone of surface water about 100 m in sea where light is sufficient for photosynthesis to exceed respiration. Euphydrayas: Genus of checkerspot butterflies, restricted to North America and Eurasia that has been the subject of intensive ecological investigations. Euploidy: Organisms having multiple of a basic chromosome number (n) for the species, such as monoploidy (n), diploidy (2n), and polyploidy (autoploidy, allopolyploidy). Eury: Broadly tolerant, as in eurythermal or euryhaline for organisms tolerating wide ranges in temperature or salt. Eusociality: This is more complex level of social behavior, which is considered to be the summit of social evolution, is called eusociality. It is highly specialized sociality characterized by cooperative caring for young, division of labor generally including (i) individuals of more that one generation living together, (ii) cooperative care of young, and (iii) division of individuals into sterile, or nonreproductive, and reproductive castes. They have overlap of at least two generations of life stages functioning to contribute to group success. Eustacy: Changing sea level resulting from changes in ice or ocean volumes. Eutorphic (Fertile): Refers to a body of water (lakes) and sometimes to other ecosystems with high in nutrients and high biological production. Eutrophication: Process of nutrient enrichment (typically of phosphates and nitrates) of a lake or stream (in aquatic ecosystems) often by runoff of fertilizer or addition of sewage, resulting in increased primary productivity. Evaporation: The process by which a liquid changes from liquid phase to a gas, as in the change from liquid water to water vapor. Evapotranspiration: Total loss of water by evaporation from an ecosystem (land and water surfaces) by evaporation and transpiration by plants mainly through the stomata. Evenness index: Index expressing equitability in the distribution of individuals among a group of species. It is a measurement of the extent to which species are equally represented in a community. Evenness: Degree of equitability in the distribution of individuals among a group of species; see equitability. Evidences of Evolution and Darwinism: According to evolutionists there are some evidences, which support the doctrine of evolution. These evidences are drawn from many areas of biology. During the first half of the 1900’s, discoveries in genetics and developmental biology were also used as evidences for the theories of evolution. In “The Origin of Species”, Darwin also disapprovingly and masterly summarized the evidences of evolution and these have been enlarged since his time. Darwin cited much of the evidence, except he had no knowledge, of course, of the biochemical data that became available after his time. Evolution: Evolution has been derived from the Latin word evolutio, means development- a gradual orderly change from one condition to another one. Evolution suggests that life arose by natural process from non-living originators and all the various plants and animals existing at the present time have descended (come down) from this. In Darwin (1859) language “I should infer from analogy that probably all the organic beings, which have ever lived on the earth have descended from someone primordial form, into which life was first breathed by the creator”. According to Geneticsts evolution is the change of gene frequencies of a gene group of an organism over time. Flowchart of evolution - Organic matter→ Unicellular organism→ Invertebrate→ Lung fish→ Amphibian→ Reptile→ Placental mammal→ Higher mammal→ Man Evolutionarily stable strategy: A strategy when common cannot be displaces by another other strategy that is rare. Evolutionary arms race: Contest over evolutionary time between two species, which causes them to evolve in response to each other. Evolutionary biology: The branch of biology that focuses on evolutionary processes and evolutionary history. Evolutionary ecology: The branch of ecology dealing with the natural selection and changes in gene frequencies in a population though time. Evolutionary opportunism: The principle that adaptations are based on whatever genetic variation is available in a population. Evolutionary time: Period during which a population evolves and becomes adapted to an environment by means of genetic change. Exclusion principle: Ecological law holding that no two species can occupy the exact same niche. Exclusion: Competitive exclusion. Exothermic process: A chemical reaction or change of phase that releases energy to the environment. Experimental design: Statistical plan for conducting an experiment, ensuring that causes associated with effects can be evaluated by carefully controlling all appropriate variables. Experimental group: In scientific experiment, a group that is treated and compared with an untreated or control group. Exploitation efficiency: The fraction of tissues at one trophic level consumed by organisms at the next trophic level. Exploitation equilibrium: Stability between predators and populations in which counterrevolutionary response of one just balance those of the other. Exploitation: An interaction between species that enhances the fitness of the exploiting individual-the predator, the pathogen etc.-while reducing the fitness of the exploited individual- the prey, host etc. Exploitative competition: A competition among members of different or the same species for the same limited resource in which one population exploits a resource, such as food, space, or common prey, to the extent that it adversely affects the other population. Exponential curve: J-shaped curve. Exponential growth: Instantaneous rate of population growth expressed as proportional increase per unit of time; a fixed percentage of the size of the population at the beginning of the period. Population growth produces a J-shaped pattern of population increase. In exponential population growth, the change in numbers with time is the product of the per capita rate of increase, r, and population size, N. Ex-situ conservation: It means the conservation of components of biological diversity outside their natural habitats. Externality: A spillover effect that benefits or harms others. The source of the effect (say, pollution) does not pay for the effect. Extinct (EX) species /Extinction: No reasonable doubt that the last individual of the species has died. It is the evolutionary termination of a species caused by the failure to reproduce and the death of all remaining men the species; he natural failure top adapt to environmental change. Extinct in the Wild (EW): Species only survives in cultivation, captivity, or as a naturalized population well outside of its native range. Extinction coefficient: Point at which the intensity of light reaching a certain depth is insufficient for photosynthesis, ratio of intensity of light at a given depth to the intensity at the surface. Extrafloral nectary: Nectar-secreting glands found on structures other than flowers, such as leaves. Extrinsic factors: Factors such as temperature and rainfall that are outside the sphere of population interactions. F F1 generation: First generation of offspring from a cross between individuals homozygous for contrasting alleles. F1 is necessarily heterozygous. F2 generation: Offspring produced by selfing or by allowing the F1 generation to breed among themselves Facilitation model: It is a model of succession. According to the facilitation model, pioneer species (previous community) prepares or ‘facilitates’ (modify) the environment in such a way that it becomes less suitable for themselves and more suitable for species (a succeeding community) characteristics of later successional stages. Factor compensation: The ability of organisms to adapt and modify the physical environment to reduce limiting factors, stress, or other physical conditions of existence. Facultative agents: A term used by Howard and Fiske to describe agents of destruction, which increase their percentage of destruction as population density rises. It is a synonymous with density-dependent factors. Facultative mutualism: A mutualistic relationship between two species that is not required for the survival of the two species. Facultative: Being able to live under different conditions or to respond to particular conditions in a variety of ways. Fall bloom: The rapid growth of algae in temperate lakes following the autumnal breakdown of thermal stratification and mixing of water layers. Fall overturn: Annual cycle in deep lakes in temperature climates, in which the warm surface water and cool subsurface water mix. Fallout: Radioactive materials produced during an atomic explosion and later deposited from the air. Family (taxonomic): A taxonomic category between genus and order. Animal family names always end in -idae; plant family names almost an always end in -aceae. For example cats and their relatives (lynexes, lions, tigers, cheetahs etc) are in the family Felidae, the human family is Hominidae and the rose family is Roseaceae. Family planning: Process by which couples determine the number and spacing of children. Fanual collapse: a dramatic loss of animal diversity, often resulting from the isolation of an area or the extinction of a keystone species. Fauna: The animals of an area. Fecundity schedules: A table of birthrates for females of different ages in a population. Fecundity: Potential ability of an organism to produce eggs or young or seeds by an organism (by a female). Feed lot: Fenced area where cattle are raised in close confinement to minimize energy loss and maximize weight gain. Feedback: Information by which a system returns toward a former condition. Female: A sex that produces larger more energetically costly gametes (eggs or ova). Fen: Wetland ecosystem dominated by sedges in which peat accumulates that received part of its nutrient input through a flow of groundwater, wetland that is only slightly acidic. Feral: Domestic plants or animals living as escapes and subject to natural selection. Fermentation: Breakdown of carbohydrates and other organic matter under anaerobic conditions. Fetch: The longest distance over which wind can blow across a body of water. It is directly related to the maximum size of waves that can be generated by wind. Fidelity: Degree of regularity or “faithfulness” with which a species occurs in certain plant communities, expressed on a five part scale: (5) exclusive, (4) selective, (3) preferential, (2) companion, indifferent, (1) accidental strangers. Field capacity: Amount of water held by soil against the force of gravity Filter effect: Influence of gaps in landscape a corridor that allow certain organisms to cross but restricts the movement of others. Fine-grained environment: An environment in which resources occur in patches so small relative to the activities of an organism that it cannot selectively forage in the patches Fine-grained: Refers qualities, aspects, or characteristic of an environment (a habitat or landscape patch), occurring in patches so small to the activity of organisms that they do not distinguish among them. First generation pesticides: Earliest known chemical pesticides such as ashes, sulfur, ground tobacco and hydrogen cyanide. First law efficiency: A measure of the efficiency of energy use. Total amount of useful work derived from a system divided by the total amount of energy put into a system. First law of thermodynamics: Also called the law of conservation of energy, which states that energy, is neither created nor destroyed; it can only be transformed from one form to another (in other words, no gain or loss of energy occurs). Fish lice: Crustacean parasites of fishes. Fission fragments: See daughter nuclei. Fission: Splitting of atomic nuclei when they struck by neutrons or other subatomic particles. Fitness: The net reproductive output of an individual i.e. number of offspring contributed by an individual relative to the number of offspring produced by other members of the population. It may be defined as the genetic contribution by an individual’s descendant to future generations. Fixation: Conversion process of an element or compound essential in soil for plant growth are converted from an unavailable (a less soluble) to an available (soluble) from. Floating reserve: Individuals in a population of a territorial species that do not hold territories and remain unmated, but are available to refill a territory vacated by the death of its holder (of an owner). Flood plain: Low lying region along river or stream, periodically subject to natural flooding. Common site for human habitation and farming. Flood pulse concept: Description of changes in a river, both laterally and longitudinally, especially during heavy rain or flooding pulse conditions. Flora: The plants of an area. Floristic: Refers to species composition of vegetation food chain; predation series linking animals to ultimate plant food. Flow pathways: Movement of matter or energy from one compartment to another. Flux: Flow of energy from a source to a sink or receiver. Fly ash: Mineral matter escaping with smokestack gases from combustion of coal. Flycatchers: A variety of birds that perches on limbs and flies out to catch insects in mid-air or perch. Foliage height diversity: A measure of the vertical structure of the vegetation in an area or in a forest. Food chain: Movement of energy (energy pathway) and nutrients from one feeding group of organisms to another (proceeding from producer to consumer) in a series in ecosystems. It is a feeding sequence such as grass →zebra→ lion, used to describe the flow of energy and materials in an ecosystem. It begins with plants and ends with carnivores, detritus feeders, and decomposes. Food cycle: Old concept now replaced with concepts of nutrient cycles (nutrients being the food) and energy flow. Food limited guild: Guild of species that compete with one another for food. Food web: Interlocking pattern of food chain formed by a series of interconnecting food chains (intertwined food chains). It is a summary (or model) of the feeding relationship within an ecological community. Foragine strategies: Ways in which animals choose their diets and allocate their time when seeking, catching, and eating food. Foraging strategy: Manner in which individual animal seeks food and allocate their time and effort in obtaining it. Forb: An herbaceous plant other than graminoid (a grass, sedge, or rush). Forching function: Independent or extrinsic variable that cause a system to respond but are not themselves affected by the system. Formation: Vegetation of a large climatic region recognized by a characteristic shape or life form. Fossil fuel: Any one of the organic fuels (coal, natural gas, oil, tar, sands and oil shale) derived from once living plants or animals. Founder’s effect: Population started by a small number of colonists, which contain only a small and often biased sample of genetic variation of the parent population, may result a markedly different new population. Fragmentation: Reduction of a large habitat area into small; reduction of leaves and other organic matter into smaller particles. Free running cycle: Length of a circadian rhythm in absence of an external time cue Freons: Fluorocarbons. Frequency of occurrence: Percentage of sample plots occupied by a particular species. Frequency-dependent selection: Differential reproduction of individuals in which the fitness of a type of individual varies with its frequency in the population. Fringing reef: A coral reef that forms near the shore of an island or continent. Frontier mentality: A mindset that view humans as above all other forms of life rather than as an integral part of nature and sees the world as an unlimited supply of resources for human use regardless of the impacts of other species. Frost pocket: Depression in the landscape into which cold air drains, lowering the temperature relative to the surrounding area; such pockets often support their own characteristic group of cold tolerant plants. Frugivore: Organism that feeds on fruit. Fuel rods: Rods packed with small pellets of radioactive fuel (usually a mixture of fissionable uranium 235 and uranium 238) for use in fission reactors. Fugitive species: Species characteristic of temporary habitats Functional response: Change (or increase) in rate of exploitation of a prey species by a predator in relation to changing prey density. It occurs in response to an increase in food (prey) availability. Fundamental niche: Niche in the absence of interspecific competition; a niche that determined in the absence of competitors or other biotic interactions such as predation. It is a total range of environmental conditions under which a species could survive. Fundamental theorem of natural selection: The average fitness of the individuals in a population increases each generation with a speed that is proportional to the variance of fitness among the individuals in the population. Fungi: A group of organisms distinct from both plants and animals, but traditionally considered with plants and studied by botanists. Fungi are largely decomposers. Mushrooms and molds are among the most well known forms. Fungi Pencillium is the source of penicillin, have been a great benefit to humans. Fynbos: Sclerophyllous shrub community occurring in regions of South Africa with a Mediterranean climate. G Gaia hypothesis: Greek, Gaia the Earth goddess; hypothesis formulated or coined by James Lovelock in 1968 to describe the earth’s capacity to maintain the physical and chemical conditions necessary for life especially microorganisms have evolved with the physical environment to provide control (selfregulation) and to maintain conditions favorable to life on Earth.. Galaxy: Grouping of billions of stars, gas, and dust, such as the Milky Way Galaxy. Gallery forest: Rain forest that occurs along banks and floodplains of rivers. Riverine forest and Riverbank forests are often called gallery forests. Game ranching: Herding native game animals instead of the standard domestic animals, especially cattle. Games theory: Theoretical approach which investigates the strategies that individuals should adopt in situations when the consequence of an individuals behavior depends on what other individuals are doing. Gamete: A haploid reproductive cell that fuses with another to produce a diploid gamete; a sperm or an egg. Gamma (γ) Diversity: Gamma diversity is the overall diversity at landscape level includes both α and β diversities. It is a difference between similar habitats in widely separated geographic regions. Gamma rays: A high energy form of radiation given off by certain radionuclide. It can easily penetrate the skin and damage cells. Gap phase replacement: A successional development in small disturbed areas within a stable plant community. It is filling in of a space left by a disturbance, but not necessity by the species eliminated by the disturbance. Gap phase succession: Successional development at a disturbed site within a stable plant community; replacement and succession in a gap in a forest caused by a disturbance such as wind for disease. Gap: Opening made in a forest canopy by some small disturbance such as wind fall, death of an individual or group of trees that influences the development vegetation beneath. Garrigue: Scrub woodland characteristic of limestone areas with low rainfall and thin, poor dry soils; widespread in the Mediterranean countries of Southern Europe. GAS: General adaptation syndrome-hormonal response to stress in vertebrates. Gashed pyramid: Population pyramid in which certain cohorts are missing or rare. Gasohol: Liquid fuel for vehicles, containing nine pars gasoline and one part ethanol. Gause principle: Principle (first demonstrated in 1932 by G. F. Gause, a Russian biologist) which states that two species cannot coexist if their niches (occupations) are the same. Gel: A gelatin like material used in electrophoresis as a medium for protein migration. Gene bank: A facility established for the ex situ conservation of individuals (seeds), tissues, or reproductive cells of plants or Gene flow: Exchange of genetic material between populations. Gene flow: Gene (= hybridization = gene migration) flow occurs when individuals move from one population to another and interbreed. Gene flow is also called gene migration. Gene migration from one population to another is called hybridization. However, gene migration or gene flow increases through hybridization. Chromosome number also changes due to hybridization. Gene frequencies: In genetics, actually allele frequency; relative abundance of different alleles carried by an individual or a population. Gene mutation /molecular evolution: Mutation changes in a gene, which is called molecular evolution (molecular mutation). Adding of an extra base, the deletion of a base or the substitution of one base even the addition, deletion or substitution of nucleotide bases are known as molecular evolution. Gene or DNA carry and transmit hereditary information; so, evolution operates via DNA or gene. As mutations inhibit metabolic process, due to mutations living organisms suffer from various diseases. Geneticists have identified more than 3,500 abnormalities arising from single-gene mutation in human. Of them the most important ones are Albinism, Sickle-cell anaemia, Glactosemia, Phenylketonuria, Polydactyly, Achondrophasia, Hunting tows disorder, Haemophelia A, Testicular feminizing syndrome etc.; Autosomal recessive diseases- Adrenogenital syndrome, Albinism tyrosine+ive, Albinism tyrosine –ive, Alfa-1antitrypsin, Cystic fibrosis, Galactosemia, S-B Thalassemia, B. Thalassemia, Gene pool: The collection (sum of) of all the genes from all the individuals in the population. Gene: Unit material of inheritance more specifically, a small unit of DNA molecule coded for a specific protein to produce one of the many attributes of a species. It is the basic unit of Mendelian heredity. Genecology: Study of population genetics in relation to the habitat conditions, the study of species and other taxa by the combined methods, and concepts of ecology and genetics. Generalist: A species with broad food or habitat preference or both. Generalists: Organisms that have a broad niche usually feeding on a variety of food materials and sometimes adapted to a large number of habitats. Generation time: Average age (Tc) at which a female gives birth to her offspring, or average time (T) for a population to increase by a factor equal to the net reproductive rate. Genet: Genetic individual that arises from a single fertilized egg. Genetic code: The arrangement of the four DNA subunits (a codon) that designate which of 20 amino acids is to be added to the end of a growing protein molecule. Genetic control (of pest): Development of plants and animals genetically resistant to pests through breeding programs and genetic engineering. Introduction of sterilized males of pest species is also known as genetic control (of pest). Genetic diversity: Diversity or maintenance of genotypic heterozygosity, polymorphism, and other genetic variability in a natural population Genetic Diversity: It refers to the variation of genes /genetic composition within or among the species. This constitutes distinct population of the same species or genetic variation within population or varieties within a species. Genetic drift: Changes in allele frequencies due to random variation or chance fluctuation in allele frequencies in a population over time without any influence by natural selection. Drift is the process by which the gene pool's composition fluctuates from one generation to another, because the alleles drawn for a particular generation have slightly different frequencies than they did in the preceding generation, even without selection. It is important in small populations. However, genetic drifts are of two types namely bottleneck (reduce population by disasters such as earthquakes, floods etc) and founder effect that is migration of small population. Genetic engineering: Manipulation of DNA including isolation of genes that are then inserted in bacteria or other organisms by using selection or gene splicing-techniques. It can be used to produce insulin and other hormones. It may also be used to treat genetic diseases. Genetic feedback: Evolutionary response of a population to adaptations of predators, parasites, or competitors. Genetic material: Any material of plant, animal, microbial or other origin containing purposeful unit of heredity. Genetic resources: It means genetic material of actual of potential value. Genetic variability: Genetic differences among individuals in a population. Genetical theory of evolution: An approach to production evolutionary change based on specified genetic mechanisms for inheritance of a trait. Genetically modified organisms (GMO): The potential impact of genetically modified organisms on biodiversity is controversial. Proponents of GMO technology say it will enable us to produce cheap drugs and food with which to alleviate starvation and poverty in developing nations. Opponents are worried this technology may have unwanted side effects, either directly on the people who use GM products or on the local ecology, where GM crops are grown. Genetics: The branch of biology that deals with heredity. Genotype frequency: The frequency of different genotypes in a population. Genotype: It is the genetic constitution of an organism that is an individual’s genetic endowment, as contrasted with its phenotype. Often restricted to the portion of the genotype affecting a single characteristic. Genus: A set of one or more species; the main taxonomic category between species and family. The generic name forms the first half of the full binomial name for a species. The plural of genus is genera. Geographic ecology: The study of ecological structure and process at large geographic scales; sometimes it is defined as the study of ecological patterns that can be put on a map. Geographic information system: A computer-based system that stores, analyzes, and displays geographic information, generally in the form of maps. Geographic variation: The almost ubiquitous phenomenon of organisms of the same species being genetically different in different parts of the geographic range. Geological time scale: More than a century ago, the geologists and the paleontologists established a comparative time scale. The ages of the divisions of geologic time are established through radioactive dating methods. Fossils allowed scientists to construct the geological time scale that traces the history of life. Geometric average: The nth root of a product of n numbers. Geometric population growth: A population growth in which generations do not overlap and in which successive generations differ in size by a constant ratio. Geometric rate of increase (λ): The ratio of the population size at two points in time: A. = Nt+1N" where Nt+l is the size of the population at some future time and Nt is the size of the population at some earlier time. Geothermal energy: Energy derived from the earth’s heat that comes from decay of naturally occurring radioactive materials in the earths. Germination: The sprouting of seeds. Germplasm: The genetic material, especially its specific molecular and chemical constitution that comprises the physical basis inherited qualities of an organism. Ginkgo biloba: Japanese maidenhair tree Ginkgo biloba (distantly related to cycad, Order- Ginkgoales) are found in the remote forest of Western China but became familiar throughout China. It is the only living member of a group of plants that was plentiful in the Mesozoic (260-130 million years ago). These plants have remained with little change for many million years. Gley soil: A gray color soil developed under conditions of poor drainage, resulting in reduction of iron, and other elements. Global climate change: Modification of the global climate resulting from the increased proportion of greenhouse gases, especially Co2, emitted as by-products of human activities. Global positioning system (GPS): A device or system that determines locations on the earth surface, including latitude, longitude, and altitude, using radio signals from satellites as references. Global stability: Ability of a community to with stands large disturbances and return to its original state. Its opposite term is neighborhood stability. Global worming: Climatic changes that cause of increasing average temperature worldwide. Glucose: A sugar involved in energy metabolism. Glucose-6-phosphate: Glucose with a phosphate group. Formation of this molecule is the first step in glycolysis, the metabolic breakdown of glucose to release energy. Glycerol: An alcohol that serves as antifreeze in some animals. GNP: Gross national product. Goby: A fish of the family Gobiidae. Gobies often sit on the bottom of a body of water and often have fins on their underside modified into a sucking disk that helps to held them in position. Gonadosomatic index (GSI): An index of reproductive effort calculated as ovary weight divided by body weight and adjusted for the number of batches of offspring produced per year. For example, the northern anchovy spawns three times per year; the weight of its ovary was multiplied by 3 for calculating its GSI. Meanwhile, the ovary weight for dogfish sharks, which reproduce only every other year, was divided by 2. Gondwanaland: The giant southern continent that resulted when Pangaea split into two fragments some 200 million years ago. The northern fragment was Laurasia. Gooseneck barnacle: A group of somewhat flattened barnacles that usually have a shell made up of five limy plates. Inspite of their superficial resemblance to clams, barnacles are marine crustaceans related to stony barnacles, acorn barnacles, and more distantly to crabs and lobsters. Gouger: General group of stream invertebrates that live and feed on woody debris. Graben: Basin formed by geological faulting. Gradient analysis: Graph depicting vegetative response to a gradient (moisture, temperature, or elevation). Gradocoen: Totality of all factors that impinge on a population, including biotic agents and abiotic factors. Gradual view: View of evolution as continuing gradual process of change. Gradualism: Darwin himself and most of his followers believed that evolution proceeded in a more gradual and preservative fashions over million of years (microevolution) than in large sudden steps. Most biologists consider the existence of gradual changes to be true. In Darwin’s language: Natural selection acts solely by accumulating slight, successive favourable variation; it can produce no great or sudden modification (Darwin, 1859). Its opposite theory is the punctuated equilibrium. Grain: The relationship of the size of landscape patches to an animal’s vagility. Graminoids: Grasses and glasslike plants, such as sedges and rushes; are classified as graminoids. Herbaceous plants other than graminoids are assigned to a forb category. Species with woody thickening of their tissues were considered as woody plants. Finally, climbing plants and vines were classified as climbers. Granivore: An organism that feeds chiefly on seeds. Granivorous food chain: Food chain origination with feeding on seeds. Grasslands: Biome found in both temperate and tropical regions and characterized by periodic drought, flat or slightly rolling terrain and large grazes that feed off the lush grasses. Grassroots (Organizations of movements): People or society at a local level, rather than at the center of major political activity Gray air cities: Older industrial cities characterized by predominantly sulfur dioxide and particulate pollution. Contrast with brown air cities. Grazer food chain: A specific nutrient and energy pathway starting plants that are consumed by grazers. Grazing food chain: A food chain in which green plants (primary producers) are eaten by grazing herbivores (primary consumers), with subsequent energy transfer up the food chain to carnivores (secondary and tertiary consumers). Great auk: Alca impennis, a penguin like diving bird of the northern oceans that became extinct in the 1840s. Green book: The book which lists the rare plants growing in protected areas like botanical gardens. Green Revolution: Developments in plant genetics in the late 50s and early 60s resulting in high yield varieties producing three to five times more than previous plants but requiring intensive irrigation and fertilizer use. Greenhouse effect: Warming of the earth’s atmosphere and surface as a result of heat trapped near the earth's surface by gases in the atmosphere, especially water vapor, carbon dioxide, methane, ozone, nitrous oxide, and chlorofluorocarbons and absorption of infrared radiation by greenhouse gases, especially CO2, in the atmosphere that was reradiated from the surface of Earth. Without the greenhouse effect earth's surface would, on the average, be about 300c colder. Gross national product (GNP): Total national output of goods and services valued at market prices, including exports and private investment. Gross primary production (GPP): The total amount of energy fixed by all the autotrophs in an ecosystem; the sum of net primary productivity plus respiration by autotrophs (GPP=NPP+R). It fixed energy per unit area by photosynthetic activity of pants before respiration; total energy flow at the secondary level is not gross production, but rather assimilation, because consumers use material already produced with respiratory losses. Gross primary productivity: The total amount of sunlight converted into chemical bond energy by a plant. This measure does not take into account how much energy a plant uses for normal cellular functions. Groundwater: Water below the earth’s surface in the saturated zone. Group selection: Natural selection between groups or assemblages of organisms that are not necessarily closely linked by mutualistic associations. It eliminates one group of individuals by another group of individuals possessing superior genetic traits. However, it is not a widely accepted by hypothesis. Grouper: A large predacious marine fish of the family Serranidae. Growth efficiency: The portion of the energy assimilated by an organism that is incorporated into new tissues. Grunt: A marine fish of the family Pomadasyidae, which hunt invertebrates in sandy areas at night, are a prominent feature of coral reefs in the Caribbean. Guild: A group of species that makes a living in the same way by exploiting the same class of resources in a similar way. Such as fruit eating birds, ambush predations, the seed-eating animals in a desert, and the fruit-eating birds in a tropical rain forest. Gyre: A large-scale, circular oceanic current that moves to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Gyttja: Mud rich in organic matter found at the bottom of or near the shore of some lakes. H Haber process: Industrial catalytic process for synthesizing ammonia from nitrogen and hydrogen, which is then used as a base for the manufacture of fertilizers. This posses discovered by Fritz Haber, a German chemist. Habitat diversity: Diversity of habitat patches in a landscape, which serves as a basis for metapopulation dynamics Habitat expansion: Increase in average breadth of habitat distribution of species in depuperete biotas, especially on islands, compared with species in more diverse biotas. Habitat fragmentation: Analysis determining how the landscape has changed by humans affecting the size, shape and frequency of landscape elements (patches, corridors, and matrices) Habitat vicariants: Species that are replacements of a form found in one habitat but that occur in other habitats. They occupy the same niche and but do not coexist in the same habitat. Habitat: Place where a plant or animal lives. It is an organism's home, such as in deep woods, running streams, coral reefs, or the human blood stream (for certain life stages of certain species of malaria parasite). Hadal zone: The deepest parts of the oceans, below about 6.000 m. Half-life: Time taken for half of radioactivity of a given amount of radioactive material to decay, producing one half the original mass. It can also be used to describe the length of residence of chemical in tissues. Halocline: Changes in salinity with depth in the oceans. Halophyte: Plant able to survive and complete its life cycle at high salinities Haplodiploidy: Sex inheritance in which males are haploid and females are diploid; the existence of haploid males and diploid females in the same species. The haplodiploidy sex determination system found in bees, wasps, and ants, in which males develop from unfertilized eggs (and thus remain haploid) and females from fertilized eggs (which are diploid). Haploid: Having a single set of unpaired chromosomes (one set of chromosomes) in each cell nucleus. Hard path: A term coined by any Amory Lovins to describe large centralized energy systems such as coal, oil or nuclear power characterized by extensive distribution of central control and lack of renewability. Hardy-Weinberg equilibrium (principle) law: A law, discovered independently in 1908 by G.H Hardy and W. Weinberg, stating that in a population mating at random in the absence of evolutionary forces such as natural selection or genetic drift, or mutation. The allele frequencies will remain constant from one generation to another. If the equilibrium is disturbed, it will be reestablished after just one generation of random mating. The genotypic ratios produced by random mating or random union of gametes at a locus with two alleles, the ratios are p2: 2pq: q2, where p is the frequency of one allele, and q is the frequency of the other. Harem: A group of females controlled by one male. Harvest method: Technique for measuring net primary productivity of herbaceous terrestrial vegetation (such as old fields or grasslands); harvests are made periodically by clipping the vegetation at ground level from randomized sample sites, sorting to species, and then drying to a constant dry weight. Harvest ration: The ratio of grain (or other edible parts ) to supporting plant tissue Hawk: Strategy of always fighting in a conflict. Hazardous waste: Any potentially harmful solid, liquid or gaseous waste product of manufacturing. Heliconia: A South American genus of banana like herbaceous plants whose family is Strelitziaceae. Heliothermic thermoregulator: An animal, whose body temperature is roughly equal to that of its surroundings and that controls its body temperature during the day by changing its position throughout the day so as to adjust the amount of solar radiation it receives. Hemicrytophyte: Perennial shoots or buds close to the surface of the ground; often covered with litter. Hemiparasite: Organism that obtains some but not all of its nutrients parasitically. Herbicide: Chemical agent used to control weeds. Herbivore: A heterotrophic organism that eats plants material. Heritability: The slope of the regression line between the phenotype of an offspring and the average phenotype of its two parents. Hermaphrodite: An organism possessing the reproductive organs of both sexes. In other word an individual capable of producing both sperm or pollen and eggs. Heteroculture: Agriculture in which several plant species are grown simultaneously to reduce insect infestation and diseases. Heterogeneity: A state of being mixed in composition. It also can refer mixed genetic or environmental composition. Heterogonic: Life cycle in which sexual and asexual reproductive episodes alternate. Heterograph: An organism that feeds on other organisms such as plants and animals. It cannot make its own foodstuffs. Heterosis: The condition in which the heterozygote is more fit than either homozygote. Heterotherm: An organism which during part of its life history becomes either endothermic or ectodermic. Forging insects such as bees become endothermic during periods of activity characterized by rapid drastic, repeated changes in the body temperature. Heterotroph: A plant, an animal, or a microorganism that cannot manufacture its own food from inorganic matter, which therefore uses organic molecules both as a source of carbon and as a source of energy (consumes other organisms for its source of energy). Heterotrophic succession: Succession beginning with P/R <1; successional process on dead organic matter. Heterotrophic: Requiring a supply of organic matter or food from the environment; depending on other organisms for food, or nourishment; a system where respiration (R) exceeds production (P). Heterozyous: The containing of two different alleles of a gene one from each parent at the corresponding loci of a pair of chromosomes. It is an adjective of heterozygote and describes an individual with different alleles at the same locus on each of its chromosomes (one derived from the father and one from the mother). Hexokinase: The enzyme responsible for adding a phosphate group to glucose to from glucose- 6phosphate in glycolysis. Hibernate: To pass the winter in inactivity that is with a greatly lowered body temperature. Hibernation: Animal can go into a state of reduced metabolism that may last several months in a dormant state. If this state occurs mainly in winter, it is called hibernation. If it occurs in summer, it is called estivation. Hierarchy: In the classification, the systems of ranks are categoried, which indicates the level of various taxa. At first Carolus Linnaeus established a definite hierarchy, which is called ‘The Linnaean hierarchy’. In includes only five categories- Class, Order, Genus, Species, and Varieties. Higher taxa: Higher taxa are those above the species level. Histosol: Soil characterized by high organic matter content. Hodrophyte: Plant that grows wholly or partly immersed in water. Holism: Greek holos, ‘whole’; theory that whole systems cannot fully be understood by investigating their individual parts or properties. These whole entities have an existence, rather than being a mere sum of their parts. Holocene: Time since end of last ice age (about 10,000 years) Holological: Refers to studies that investigate the ecosystem as a whole, rather than examining each component part. Holozoon: Organism, such as a wolf or rat, which feeds on relatively large pieces of dead organic matter. Home habilis: Link between Australopithecines and Homo erectus. Home range: An area through which mobile animals regularly move in the course of their normal activities. The empirical determination of home range typically involves monitoring the movements of an individual by plotting them on a map, then joining the outermost points to form a minimum convex polygon. Homeostasis: A tendency of a system to resist change and maintain itself in a state of stable equilibrium; maintenance of nearly constant conditions in function of an organism or in interaction among individuals in a population. Homeostasis: The maintenance of equilibrium in an organism or biological system. Homeotherm: An organism that uses metabolic energy to maintain a relatively constant body temperature; such organisms are often called warm-blooded; also spelled homoiotherm and homotherm. Homing: Ability of an individual to navigate a long distance in order to find its way back to its home area. Homo erectus: The immediate ancestor of Home sapiens Java and Peking people. Homoiohydric: Ability to maintain a stable internal water balance independent of the environment. Homoiothermy: Regulation of body temperature by physiological means. Homologus chromosomes: Corresponding chromosomes from male and female parents homozygous are containing two identical alleles of a gene at the corresponding loci of a pair of chromosomes. Homology: The condition of having similar evolutionary or developmental origin. Homozygous: Containing two identical alleles at the same loci of a pair of chromosomes; an individual with the same alleles at a particular locus on both of its matching chromosomes. Honeyeaters: A large bird group (Family: Meliphagidae), consisting of some 170 species of birds of the Southwest Pacific and Australia. They have long bill, brush-tipped tongues and feed on nectar (hence their name), insects, and fruit. Horizon: Major zones or layers of a soil each with its own particular structure and characteristics. Host: An organism that provides food or other benefit to another organism of a different species. It is usually refers to an organism that can be infected or exploited by a specific parasite. Hot-rock zones: Most widespread geothermal resource. Regions where bedrock is heated by underlying magma. Hotspot: A biodiversity hotspot is a place with many more species than the expected form. Human ecology: Study of the impact of humankind on and integration with natural systems. Humification: Production of humus during the decay of biological materials. Humus: A dark, decaying organic substance derived from partial decay of plant and animal matter found in soils. It increases soil fertility, aeration and water retention. Hunting and gathering society: People that lived as nomads or in semi permanent sites from the beginning of human evolution until approximately 5000 B.C. Some remnant populations still survive. They gathered seeds, fruits, roots and other plant products for food. Hybrid: Plant or animal resulting from a cross between genetically different parents. Hydrarch succession: Progression of terrestrial plant communities developing in an aquatic habitat such as a bog or swamp. Hydrarch succession: Sequential colonization of marshy habitats. Hydrarch: Succession on wetlands. Hydrocarbons: Organic molecules containing hydrogen and carbon. It releases during the incomplete combustion of organic fuels. It reacts with nitrogen oxides and sunlight to form photochemical oxidants in photochemical smog. Hydroelectric power: Electricity produced in turbines powered by running water. Hydrologic cycle: The movement of water through the biosphere during evaporation, transpiration, condensation, precipitation, and runoff. It is also called the water cycle. Hydrology: Study of water both quantitively and qualitatively, as it moves through the hydrological cycle. Hydroperiod: Periodicity of water-level fluctuations. Hydrosphere: Body of water on or near the earth surface; the portion of the earth containing water in liquid or vapour form. Hydrothermal vents: Sites in the ocean bed, usually near a mid oceanic ridge, releasing geothermally heated water. The water is rich in dissolved sulfides, which are oxidized by chemosynthetic bacteria, providing organic compounds that support animal communities. Hyperosmotic: A term describing organisms with body fluids with a lower concentration of water and higher solute concentration than the external environment. Hyperthermia: Rise in body temperature to reduce thermal differences between an animal and a hot environment thus reducing the rate of heat flow into the body Hypervolume niche: A multidimensional space concept proposed by G.E. Hutchinson in 1957, in which the niche of a species is represented as a point or volume in a hyperspace whose axes correspond to attributes of that species Hyphae (Hypha): Long, thin filaments that form the basic structural unit of fungi. Hypolimnion: The deepest layer of a lake below the epilimnion and thermocline. It is a cold, oxygenpoor, bottom part of a lake or water that is too deep to be warmed by the sun or mixed by the wind and lies below the thermocline. Hypo-osmotic: A term describing organisms with body fluids with a higher concentration of water and lower solute concentration than the external environment. But those with body fluids with a lower concentration of water (higher solute concentration) than the external medium are hyperosmtic and are subject to water flooding inward from the environment. Hyporheic zone: A zone below the benthic zone of a stream; a zone of transition between surface, stream water flow, and groundwater. Hypothesis: A proposed tentative idea or concept explanation for a natural phenomenon that should be testable for acceptance or rejection by experimentation I Ice age: Period during the last two million years characterized cold climate with glaciers and little vegetation. Ichthyology: The study of fishes. Ideal free distribution: A distribution of individuals across resource patches of different intrinsic quality that equalized the net rate of gain when competition is taken into account. Illuvial horizon: Soil layer to which matter has been added from above. Immature ecosystem: An early successional community characterized by low species diversity and low stability. It may contrast with mature ecosystem as its opposite term is mature ecosystem. Immigration: Arrival or movement of new individuals into a habitat or population; movement of people into a country to set up residence there. Immobilization: Conversion of an element from inorganic to organic from in microbial or plant tissue, rendering the nutrient relatively unavailable to other organisms. Implala: One of the well-designed of African antelopes (Aepyceros melampus). The males have graceful, lyre-shaped horns, the females are hornless. Importance value: Sum of relative density, relative dominance, and relative frequency of a species in a community on scale from 0 to 300 the higher the importance value, the more dominant is that species in that particular community. Imprinting type: Of rapid learning at a particular and early stage of development in which the individual learns identifying characteristics of another individual or object. In situ conservation/ conditions: It means the conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings and, in the case of domesticated or cultivated species, in the surroundings where they have developed their distinctive properties. Inbreeding depression: Detrimental effects of inbreeding, resulting in an inadequate gene pool. Inbreeding: Mating between or among close relatives. Inbreeding tends to increase levels of homozygosity in populations and often results in offspring with lower survival and reproductive rates. Incipient lethal temperature: At which a stated fraction of a population of Poikilothermic animals (usually 50 percent) will die, when brought rapidly to it from a different temperature. Inclusive fitness: Sum of the total fitness of an individual (overall fitness), which is determined by the survival and reproduction capacity of an individual. Genetically the number of copies of an individual’s genes that are placed in the next generations gene pool, as a result of its reproductive activities of its relatives. Independent variable: Variable x which yields the first of two numbers in an ordered pair (x y) the set of all values taken on by the independent variable is called the domain of the function. Indicator species /organism: A species whose status provides information on the overall condition of the ecosystem and of other species in that ecosystem. That is this organism indicates the presence or absence of a certain environmental conditions. Individualstic concept: A concept of community development first proposed by H.A. Gleason in 1926 and stated that species of plant is distributed individually with respect to biotic and abiotic factors, thus associations result only from similar requirements. Indoor air pollution: Generally refers to air pollutions in homes from internal sources such as smokes, fireplaces, wood stoves, carpets, paneling, furniture, foam insulation and cooking stoves. Induced abortion: It is a surgical procedure to interrupt pregnancy by removing the embryo or fetus from the uterus. In the first trimester, generally carried out by vacuum aspiration. Spontaneous abortion is an opposite term of induced abortion. Inductive method: In testing hypotheses, going or reasoning from the specific to the general. Industrial melanism: Evolution of dark coloration in moths in heavily industrialized areas. Industrial smog: Air pollution from industrial cities (gray-air cities) consisting mostly of particulates and sulfur oxides. Contrast with photochemical smog. Industrial society: Group of people living in urban or rural environments that are characterized by mechanization of industrial production and agriculture. Widespread machine labour causes highenergy demands and pollution. Increasing control; over natural processes leads to feelings that humans are apart from nature and superior to it. Inertia: Tendency of an ecosystem to resist change. Inertial thermoregulators: Animals such as large reptiles that develop body temperatures above the air temperature because their low surface- to-volume ratio limits cooling. Infant mortality rate: Number of infants under 1 year of age disappearing per 1000 births in any given year. Infanticide: Killing of offspring by other individuals in the same species. Infauna: Animals living within sediments of sea floor or on the ocean bottom.. Infaunal: Organisms living within a substrate. Infectious disease: Generally, a disease caused by a virus, bacterium, or parasite that can be transmitted from one organism to another. Inflorescence: A cluster of flowers with a definite arrangement; inflorescences of some plant families, such as the Composite, look like individual flowers to the uninitiated. Infralittoral: Region below the littoral region of the sea. Infrared radiation: Heat radiation of too long a wavelength to be visible to the human eye. Infrared radiation: Heat, an electromagnetic radiation of wavelength outside the red end of the visible spectrum. Ingestion: Taking of food into the gut; process by which heterotrophs such as animals take in their food. Inhibition model: A model of succession that proposes that early occupants of an area modify the environment in a way that makes the area less suitable for both early and late successional species. Inland wetlands: Wet or flooded regions along inland surface waters. Includes marshes, bogs and river outflow lands. In-migration: Movement of people into a state or region within a country to setup residence. Input approach: A method of solving an environmental problem by reducing the inputs. For example, reducing consumption and increasing product durability can cut production of solid wastes, pollution or hazardous wastes. Input management: Strategy of managing system inputs rather than system outputs; source reduction approach to reducing pollution. Insecticide: One from of pesticide used specifically to control insect populations. Insectivore: A heterotrophic organism that eats mainly on insects. Instar: Form of insect or other arthropod between successive molts. Insularization: Division into islands or island like units. Integrated pest management (IMP): Program or management strategy designed to use of a variety of ecologically sound techniques (minimum application of pesticides, use of different methods and farming strategies) such as chemical, biological, physical or cultural to keep pest populations below the size at which they cause serious economic damage (i.e. to suppress pest populations below their economic threshold). Integrated wildlife or species management: Control of population through the use of many techniques, including the reintroduction of natural predators, habitat improvement, reduction in habitat destruction establishment of preserves, reduced pollution and captive breeding. Intellectual property right (IPR): A right enabling an inventor to exclude imitators from the market for a limited time. Inter sexual selection: The situation in which members of one sex create a reproductive differential in the other by preferring some individuals as mates. Interaspecific competition: Competition between individuals of the same species. Interdemic selection: Group selection of populations within a species. Interdisciplinary: Approaches resulting in cooperation among members of different scientific disciplines when addressing a higher level concept, problem, or question. Interference competition: Form of competition involving direct antagonistic interactions between individuals; in which one species prevents the other from having access to a limiting resource (as oppose to exploitation competition). Interglacial: Warmer interval between ice ages. Interior species: Individuals chiefly birds and mammals that inhabit the interior of a forest or grassland ecosystem rather than its edges. Intermediate disturbance principle: The proposition that the highest species diversity in an association of space-limited competitors occurs at an intermediate degree of disturbance. Intermediate host: Hosts which harbor developmental phases of parasites; the infective stage or stages can develop only when the parasite is independent of its definitive host. Intersexual selection: Sexual selection occurring when members of one sex choose mates from among the members of the opposite sex on the basis of some anatomical or behavioral trait, generally leading to the elaboration on the basis of some particular feature. Because two sexes are involved, this form is called intersexual selection. Examples of character used for mate selection include female birds choosing among potential male mates based on the brightness of their feather colors or on the quality of their songs. Interspecific competition: Competition between individuals of different species. Interspecific territoriality: Defense of a territory against individuals of other species. Intraspecific: Competition between individuals of the same species. Intrinsic factors: Population fluctuations controlled primarily by regulatory mechanisms (genetic, endocrine, behavioral, disease, and so on) within the population Intrinsic rate of increase: The maximum per capita rate of population increase (r or rmax) based on a table age distribution and freedom from competition and limiting resources. It may be approached under ideal environmental conditions without inhibition from competition for a species. It is the difference between the density-independent components of the birth and death rates. Introduced / Exotic species/Aline species: Exotic organisms that have arrived from other parts of the world (often because humans have transported them) are known as introduced or alien species. The impact on local ecosystems are – (a) they may prey on native species or (b) they may compete for resources with native species. (c) interbreed with native organisms and this unnatural hybrids may differ greatly from well-adapted native plants and animals. Introgression: Incorporation of genes of one species into the gene pool of another Invasion structured guild: A guild of species whose body sizes represent the result of successive invasions. Invasive alien species: A species which does not occur naturally in a place, and spreads rapidly over large areas e.g. spreading of African magur in Bangladesh. Invasive: The tendency to invade or to enter a new location or niche. Inversion (genetic): Reversal of a part of a chromosome so that genes within that part lie in reverse order. Inversion (meteorological): increase rather that decrease in air temperature with high caused by radiation cooling of the earth or by compression and consequent beating of subsiding air masses from high pressure areas (subsidence inversion) Invertebrates: Animals without backbones- for example, insects, worms, and mollusks. Inverted pyramid of numbers: Situation in which more individuals at one trophic level exist than at the trophic level beneath. Ion: A particle formed when an atom loses or gains an electron. Ionizing radiation: Electromagnetic radiation with the capacity to form ions in body tissues and other substances that capable of causing mutations. Irradiance: The level of light intensity, often measured as photon flux density. Irruptive: The tendency to increase suddenly in numbers Isat : The irradiance required to saturate the photosynthetic capacity of a photosynthetic organism. Island biogeography: The study of the distributions of organisms on islands. Through this study the number of species on an island is determined by the equilibrium between the immigration of new species and the extinction of species already present. Isoclines of zero population growth: Lines in the graphical representation of the Lotka-Volterra competition model, where population growth of the species in competition is zero. Isohyet: Line on a map connecting places of equal precipitation. Isolation mechanism: Any structural behavioral or physiological mechanism that blocks or inhibits gene exchange between two populations Isolation: Absence of migration. Isopleth: Line of constant precipitation–evaporation ratio. Isosmotic (Organisms): A term describing organisms with body fluids containing the same concentration of water and solutes as the external environments are isosmotic. Isostacy: Changing sea level due to crustal movements under ice masses. Isotherm: Lines drawn on a map connecting points with the same temperature at a certain period of time. Isotopes: Atoms of the same element that differ in to heir atomic weight (but with virtually identical chemical properties) because of variations in the number of neutrons in their nuclei. Isozymes: All enzymes with the same biochemical function that are produced by different or the same loci. Iteroparity: Reproduction that involves production of an organism's offspring in two or more events generally spaced out over the life time of the organism. Iteroparous: A species in which individuals reproduce several times during their lives. IUCN: International Union for the Conservation of Nature and Natural Resources. J Jawless fishes: Fishes with sucking mouths and no bones (class Agnatha) e.g. Hagfishe and Lampreys. J-shaped growth curve: J-shaped pattern of population growth that occurs when the population density increases in exponential fashion Jurassic: middle period of the Mesozoic some 190 to 135 million years ago with warm, humid climate. In these period dinosaurs abundant, bony fishes evolving rapidly and gymnosperms dominant; K Karst: Lake occupying a solution basin. Kerojen: Solid, insoluble organic material found in oil shale. Key Factor analysis: Statistical analysis of population processes accountable for changes in population size. Keystone mutualist: A species upon which other species depend for their persistence at a site. Keystone predator: A predator whose removal leads to reduced species diversity among the prey. Keystone species: Functional group or population without redundancy; a species (such as a predator) having exert strong effects (a dominating influence) on the structure of the communities. Kilocalorie: Roughly the amount of heat energy required to raise the temperature of 1 kg (2.2 lb) of water 10c (1.80f). Kilowatt: One thousand watts. Kin selection: Selection in which individuals increase their inclusive fitness by helping increase the survival and reproduction of relatives (kin) that are not offspring. It is a selection favoring an altruistic trait, because the survival and reproduction of close relatives of the altruist are sufficiently enhanced. Kinetic energy: The energy of objects in motion. Kiwi: Apteryx Australia, a virtually wingless nocturnal bird from New Zealand. It is a distant relative of the ostrich and other Southern Hemisphere flightless birds. The kiwi nearly became extinct after Europeans settled New Zealand, but now it is totally protected and apparently flourishing. Knogoni: Alcelaphus buselaphus, an African antelope with short horns, which appear to be fused at the base; also called Coke’s harte-beeste. Krange syndrome: Leaf morphology required for C4 photosynthesis in which chloroplasts are in cells below the epidermis. Krummholtz: Stunted from of tress characteristic of transition zone between apline tundra and subalpine coniferous forest. K-selection: A term referring to the carrying capacity of the logistic growth equation; a form of natural selection that favours more efficient utilization of resources such food and nutrients. K- selection is predicted to be strongest in those situations where a population lives as densities near carrying capacity much of the time. K-selection: Selection under carrying capacity and high level of competition; characterized by Kselection tend to dominate mature stages of ecological succession. Kudzu vine: Pueraria thunbergiana, a leguminaceous vine from china and Japan that is widely used for control of erosion. L La Nina: The opposite of an EI Nino. During a La Nina, the sea surface temperature in the eastern Pacific Ocean is lower than average and barometric pressure is higher. Lag effect: The tendency for a population to continue growing even after it has reached replacement level fertility. It is caused by an expanding number of women reaching reproductive age. Lagg: Moat like area of shallow water, often dominated by sedges, surrounding a peat mat. Lamarck: The first modern theory of evolution was forwarded by Jean Baptist de Lamarck (1744-1829), a French botanist who proposed the theory of inheritance of acquired characters, popularly known as Lamarckism. Lamarck began his career as a botanist but later became a Zoologist. Lamarck published his theory in his book ‘Philosophic Zologique’ in 1809. During his lifetime he became controversial. Lamarck died penniless in Paris on 28th December, 1829. LAMARCK’S THEORY: Lamarck’s theory focuses on the idea of uses and disuses of parts, and inheritance of acquired characters. This theory is based on environmental factors, and summarized in the sentence that ‘Function creates an organ. Followings are the four important postulates on which Lamarck’s theory of inheritance of acquired characters based-(a) The first principle is that living organisms and their organs tend continually to increase in size. (b) The second principle is that new organs resulted from new needs and desires. (c) According to the third principle those organs will develop due to use and degenerate due to disuse. (d) Modifications produced by the above principles during the lifetime of an individual will be inherited by its offspring’s, with result that changes are increasing over time. To explain his theory Lamarck used examples like long neck of giraffe, limblessness in snakes, blindness of moles and so on. Land use planning: Process whereby land uses are matched with the needs of the community and environmental consideration-for examples, need for open space and agricultural and for control of water and air pollution. Landform: Any distinctive feature of the earth's surface. Landnam: Hypothetical land clearing by early European agriculturalists and recorded by elm pollen decline. Landraces: A crop cultivar or animal breed that evolved with and has been genetically improved by traditional agriculturalists not been influenced by modern breeding practices. Landscape architecture: Study of the structure and three dimensional use of habitat space in the field of landscape ecology Landscape corridor: Strip of vegetation that differs from the matrix and frequently connects tow or more patches of similar habitat Landscape ecology: The study of landscape structure processes, function and change in a heterogeneous landscape composed of interaction ecosystems. Landscape elements: The ecosystems in a landscape, which generally form a mosaic of visually distinctive patches. Landscape geometry: Study of shapes, patterns, and configurations at the landscape scale. Landscape matrix: Large area of similar ecosystem or vegetation types (agricultural or forest, for example) in which landscape parches are embedded. Landscape mosaic: Quilt-like patches of different types of vegetative cover across a landscape, cluster of ecosystems of different types Landscape patch: Relatively homogeneous area that differs from the surrounding matrix (such as a woodlot embedded in an agricultural matrix). Landscape process: The exchange of materials, energy, or organisms among the ecosystems that make up a landscape. Landscape structure: The size, shape, composition, number, and position of ecosystems within a landscape. Landscape: A regional level of organization between the ecosystem and the biome that are repeated in a similar manner throughout the area, landforms of a region in the aggregate. Landscape: An area of land containing a patchwork of ecosystems. Langley: Flux of solar energy measured as gram-calories per unit area in unit time. Langmuir cell: Localized area of water a few meters wide and hundreds of meters long created by the wind; involves a local circulation pattern of upwelling water that diverges from the center converges, and sinks at the boundaries. Large young strategy: Concentrates resources into a few young, either by making young large or through parental care. Large-scale phenomena: Phenomena of a geographic scale than a local scale. Larva: An early, free living developmental stage of an animal that does not resemble the adult. A caterpillar is the larva of a butterfly or moth, a maggot the larva of a fly, a tadpole the larva of a frog or toad. Laten heat of fusion: Number of calories given up by 1 g of water. It is the amount of heat given up when a unit mass of a substance converts from a liquid to a solid state or the amount of heat absorbed when a substance converts from the solid to liquid state. Latent heat of evaporation: Number of calories required to evaporate 1g of water. Laterite: Soil found in some tropical rain forests. It is rich in iron and aluminum but generally of poor fertility, thus bricklike if exposed to sunlight. Laterization: Soil forming process in hot humid climates characterized by intense oxidation resulting in loss of bases and in a deeply weathered soil composed of silica, sesquixides of iron and aluminum, clays, and residual quartz. Laurasia: The northern fragment of Pangaea; the southern fragment was Gondwanaland. Law of diminishing returns: As an ecosystem becomes larger and more complex the proportion of gross productivity that must be respired to sustain growth increase (in other words, the proportion of productivity that can go into further growth declines). Law of Thermodynamics: Laws that describe energy. The most powerful and fundamental generalization that can be made about the universe is the laws of thermodynamics. Law of thermodynamics laws are regarded as laws because all attempts to disprove it have been failed, despite a large number of painstaking observations and ingenious experiments were conducted. These laws are fully appreciated and universally accepted by all branches of sciences from material to spiritual world. First Laws of thermodynamics: The first law of thermodynamics says that energy is conserved. The second law says that as a result of all spontaneous processes the availability of energy decreases. LD50: It is known as median effective lethal dose of a poisonous substance that will kill half (50%) of the test population i.e. 50% mortality. It usually expressed in term of milligrams (mg) of toxicant per kilogram (kg) of body weight of test animal. LD90: The dose of a poisonous substance which causes death 90% of the test population. LC50: It is a concentration of a poisonous substance that will kill 50% of the test population. LT50: It represents the time require killing 50% of the test population by a poisonous substance. Leach: Dissolve in and removal of nutrients by water percolation through the soil. Leaf cutter ants: Members of the ant tribe Attini that eat fungi, growing on a mulch of cut leaves in special chambers of their nests called fungus gardens. Parades of workers of these ants each carrying a cut piece of leaf like an umbrella, are a common sight in the tropics of the Western Hemisphere, where they are major herbivores in tropical forests. Lek: Communal breeding ground or an area, where males display and females come to be mated. Lentic or Lentic habitats: Refers to standing- water ecosystems (or standing water habitats) such as lakes and ponds. Lepidoptera: The insect order containing butterflies and moths. Less development country: Term describing the nonindustrialized nations, generally characterized by low standard of living populations, growth rate, high infant mortality, low material consumption, low per capita energy consumption, low capita income, rural population, and high illiteracy. Levee: Sandy bank built up at the side of a river. Levels of biodiversity: Theoretically there are three levels of biodiversity such as-genetic diversity, species diversity, and ecological diversity but all three are intertwined in such a way that is practically impossible to separate. Levels of organization: A hierarchical arrangement of order ranging from the ecosphere to cells illustrating how each level manifests emergent properties that are best explained at that particular level of organization. Lichen: Organism that consists of a fungus (the mycobiont) and an alga or cyanobacterium (the phycobiont) living in a mutualistic association. A lichen may be crustose, foliose, or fruticose according to species. Liebig law of the minimum: Concept, first stated by Baron J. von Liebig in 1840, that the essential material or resource most closely approaching the minimum need tends to be the limiting one. Life expectancy: Average number of years to be lived in the future by members of the population. Life form: Characteristic structure of a plant or animal. Life history: The adaptations of an organism that influence aspects of its biology such as the number of offspring it produces, its survival, and its size and age at reproductive maturity. Life table: A table of age-specific survival and death, or mortality, rates in a population. It is a tabulation of mortality and survivorship schedules of a population based on an initial cohort. A life table made from data collected in this way is called a cohort life table. A life table combined wit a fecundity schedule can be used to estimate net reproductive rate (R0), geometric rate of increase (λ), generation time (T), and per capita rate of increase (r).Life table can be used to draw survivorship curves, which generally fall into one of three categories (i) type I survivorship, in which there is low mortality among the young but high mortality among older individuals, (ii) type II survivorship, in which there is a fairly constant probability of mortality throughout life, and (iii) type III survivorship, in which there is high mortality among the young and low mortality among older individuals. Life zone: Concept early classification of major vegetation types put forth by C.H. Merriam in 1894, based on the relationship between climate and vegetation. A major area of plant and animal life equivalent to a biome; transcontinental region or belt characterized by particular plants and animals and distinguished by temperature differences. It applies best to mountainous regions where temperature changes, accompany changes in altitude. Life-form: The life-form of a plant is a combination of its structure and its growth dynamic. Plant life forms include trees, vines, annual plants, sclerophyllous vegetation, grasses, and forbs. Light compensation point: The light level at which photosynthesis just balances respiration. Light reaction: Light dependent sequence of photosynthetic reactions; the first part of photosynthesis, ATP (adenosine triphosphate) stores energy in phosphate bonds, and NADPH (nicotinamied adenosine dinucleotide phosphate) stores energy as the ability to reduce other compounds. Light saturation level: That value of photos athletically active radiation (PAR) at which any further increase results in no further increase in photosynthesis Light water reactor: Most common fission reactor for generating electricity. Water bathes the core of the reactor and is used to generate steam, which turns the turbines that generate electricity. Light year: Astronomical unit that measures the distance that light can travel in a year. Lignotuber: Specialized structure on the roots of certain fire adapted trees, particularly eucalyptus, from which new growth sprouts following a fire Limit cycle: A stable, sustained oscillation in the population sizes of species, usually involving predator and prey interactions models. Limit cycle: Stable oscillation in the population levels of a species. Limiting factor: A chemical or physical factor that determines whether an organism can survive in a given ecosystem; resource that limits the abundance, growth, and distribution of an organism or species. In most ecosystems, rainfall is the limiting factor. Limiting nutrient: Nutrient, which if present in greater amounts would lead to an increase in the growth or reproduction of an organism. Limiting resource: A resource or environmental condition that is in short supply compared with the demand for it. Limiting similarity: The maximum degree of similarity that two species can have and still coexist. Limits of tolerance: Upper and lower limits to the range of particular environmental factors (such as light or temperature) within which an organism or species can survive. Limnetic zone: Shallow water zone of lake or sea in which light penetrates to the bootom where P/R>1. Limnetic: Pertaining to or living in the open water of a pond or lake beyond the littoral zone. Lincoln index: Formula used to estimate the population size from mark-recapture data. Lindeman’s law of trophic efficiency: A belief that the efficiency of energy transfers from one trophic level to the next is about 10%. Lindeman's efficiency: The ratio of energy acquired by one trophic level to the acquired by the next, also called ecological efficiency. Lindemans: Efficiency is the product of the absorption efficiency, the growth efficiency, and the exploitation efficiency. Liquefaction: Production of liquid fuel from coal. Liquid metal fast breeder: Fission reactor that uses liquid metals such sodium as a coolant Lithosol: Soils very low in organic matter and composed of rock fragments or nearly barren rock. Lithosphere: Rocky material of the earth outer crust. Little ice age: Period from AD 1540 to 1700, notable for many long cold winters and cool summers. Littoral drift: Movement of beach sand parallel to the shore line caused by waves and long shore currents parallel to the beach. Littoral zone (or littoral): Near-shore zone of sea or lake or ocean shore, where enough light for photosynthesis can reach the bottom and rooted aquatic plants may grow in lakes. Littoral: Occurring at the border of the land and sea. Local stability: An ability of system to return of its primary conditions following a small disturbance. Loci (locus): The location or site along the length of a particular chromosome, where a specific gene is located. Loess soil: Developed from wind deposited material. Loess: Wind-blown soil deposits originating from debris left by retreating glaciers. Log normal distribution: Normal distribution in which the horizontal axis is calibrated or expressed in a logarithmic scale. In the frequency distribution of species, the x-axis represents the number of individuals and the y- axis represents the number of species. Logistic curve: S-shaped curve of population growth, which slows at first, steepness and then flattens out at asymptote determined by carrying capacity. Logistic equation: It is mathematical expression for the population growth curve in which rate of increase decreases linearly as population size increases; dn/dt = rmn(K – N/K). Because the population growth rate declines as the carrying capacity is approached, a population growth curve shaped like an S stretched left to right. Logistic growth: Pattern of population growth producing a sigmoid (S-shaped) curve; population size levels off at carrying capacity (K). Long day organism: Plant or animal that requires long days (days with more than a certain minimum of daylight) to flower or come into reproductive condition. Lotic habitat: Running water-habitat ecosystems, such as a stream or river. Lotic: Persuading to flowing warmer. Lotka-Volterra equations: Model developed in the 1920s by Alfred Lotka, an American mathematician and Vito Volterra, an Italian mathematician based on the logistic equation, précising interspecific competition such as predator prey relationships Lower critical ambient temperature: Surrounding temperature below which warm-blooded animals must generate heat to maintain their body temperature. Lower risk (LR): Species does not satisfy criteria for above categories, but may be near threatened or dependent on conservation activities for survival. Luxury consumption: Uptake to nutrients by algae in excess of immediate needs. M Maar: Volcanic explosion crater. Macroclimate: The current climate for a region. Macrocosm: A large sized experimental or natural ecosystem. Macroevolution: Evolution above the population level involving quick major phenotypic changes and the divergence and history of major groups. Macronutrients: Essential nutrients (elements) needed in relatively large amounts by plants and animals such as nitrogen, and phosphorus. Macroparasite: Parasitic worms, lice, fungi and the like those have comparatively long generation time. Macrophytes: Rooted or large floating plants such as water lilies. Magma: Molten rock beneath the earth's crust. Maintenance energy: Resting or basal rate of metabolism plus the energy essential to cover minimum activities under field conditions Malathion: An organophosphate insecticide with relative low mammalian toxicity. Male: Sex that produces smaller less costly gametes (sperm or pollen). Malnourishment: A dietary deficiency caused by lack of vital nutrients and vitamins. Malthus’s theory: Thomas Reverend Malthus (1766-1834), an English clergyman and economist, developed a theory of population growth that warned of impending social chaos. He wrote a book. "An Essay on the Principles of Population" (1798), which was an instantaneous best-seller and since then has influenced the thinking of people all over the world about population and economic growth. Malthus argued that there is a natural tendency of population growth. He pointed out that population increases exponentially but food supply is limited as it depends on fixed amount of land. For this reason, human species will face war, plague and famine due to food shortage. According to Malthus, when population is unchecked, goes on doubling itself every twenty-five years, and increases in a geometrical ratios of 2, 4, 8, 16, 32, 64 ---- people becomes so large that there will be not enough space in the world for all the people to even stand. The means of survival, under circumstances the most favorable to human industry, could not be possible to make to increase faster than in an arithmetical ratio of 1, 2, 3, 4, 5, 6, 7, 8 ----. Manganese nodules: Nodular accumulations of manganese and other minerals such as iron and copper found on the ocean floor at depths of 300 to 6000 meters. It is particularly abundant in Pacific Ocean. Mangrove forest: A forest of subtropical and tropical marine shores dominated by salt-tolerant woody plants, such as Rhizophora and Avicennia. Mangrove: Mangroves are salt-tolerant ecosystems in tropical and sub-tropical regions. These ecosystems are largely characterized by crowd of unrelated tree genera that share the common ability to grow in saline and twin zones. Mangroves play important role in stabilizing shorelines and protecting them from cyclones. Mangroves: Emergence of woody plants that tolerate the salinity of the open sea; trees that dominate tropical inter tidal forests Maquis: Sclerophyllous shrub vegetation in the Mediterranean region. Marasmus: A dietary deficiency caused by insufficient intake of protein and calories and occurring primarily in infants under the age of 1, usually as the result of discontinuation of breast feeding. Margallitic soil: Tropical mollisol important to tropical agriculture. Mariculture: Cultivation of fish and other aquatic organisms in salt water (i.e. in estuaries and bays). Mariculture: Fish or other food farming in enclosures (mesocosms) in bays and estuaries. Marine Park: Marine Park is a place where (marine area) leisure and educational activities are permitted. But no commercial activities are allowed and all collecting requires a permit. Marine protected areas (MPA): A marine area, including habitats, endangered species etc. where some level of protection is maintained for conservation. Marine reserve: A marine area where no activities are permitted. Mark release-recapture: A technique for estimating population size and determining movement patterns by finding the proportions and locations of previously marked and released animals. Marl: Unconsolidated deposit formed in fresh water lakes that consist chiefly of calcium carbonate mixed with clay and other impurities. Marsh: Wetland ecosystem with occasionally waterlogged mineral soils, dominated by grassy vegetation, such as cattails and sedges. Masting: The synchronous production of large quantities of fruits by trees, such as oaks and beech. Mating system: The pattern of mating within a population, including how mates find one another, how many mates individuals have, and how long mates remain associated. Matric force: A force resulting from water's tendency to adhere to walls of containers such as cell walls or the soil particles lining a soil pore. Mattoral: Sclerophyllous shrub vegetation in regions of Chile with Mediterranean climate. Mature community: A community that remains more or less the same over a long period of time. Climax stage of succession. Also called a climax community. Mature ecosystem: An ecosystem in the climax stage of succession characterized by high species diversity and high stability. This term is Comparable with immature ecosystem. Maximum carrying capacity (km): Maximum density that the resources in a particular habitat can support. Maximum sustained yield: The point in a population growth curve where harvested biomass would be most quickly replaced, the maximum rate at which individuals in a population can be harvested with no dropping its size. Measure of economic welfare: Proposed standard that takes into account the accumulated wealth of a nation. Mechanical weathering: Breakdown of rocks due to the action of water, heat and wind. Mediterranean climate: A maritime or semiarid climate with mild winter rain and hot, dry summer. Megalopis: A large continuous urban area formed by the union of two or more cities. Megawatt: Measure of electrical power equal to a million watts, or 1000 kilowatts. Meiofauna: Benthic organisms within the size range of 1 to 0.1 mm; interstitial fauna. Meiosis: Two successive divisions of cell nuclei, resulting in the diploid chromosome number being reduced to the haploid number in daughter cells and in the course of which recombination occurs. Melanic: Very dark colored or black. Mendelian genetics: The transmission of traits according to the rules first discovered by the Austrian monk Gregor Mendel. Meristematic tissue: Tissue made up actively dividing cells responsible for plant growth. Merological: It refers to a study that examines component parts first in an effort to understand the system as a whole. Meromictic lake: Permanently stratified lake. Mesic: Describes moist habitat conditions; an environment with plenty rainfall and a well-drained soil. Mesocosm: A midsized experimental ecosystem. Mesopelagic zone: A middle depth zone of the oceans, extending from about 200 to 1,000 m depth of the oceans. Mesophyte: Plant that grows in environmental conditions that are medium in moisture conditions. Mesosphere: A layer in the earth's atmosphere, extending from 64 to 80 km above the earth's surface where temperatures drop steeply with altitude in this atmospheric layer. Mesothelioma: A tumor of the lining of the lung (pleura), caused by asbestos. Mesotrophic: Moderately fertile. Mesozoic era: The geological era 225 -65 million years ago, the age of the dinosaurs. Mesozoic middle: Era in the geological time scale some 230 to 70 million years ago; age of reptiles three main periods are Triassic, Jurassic and Cretaceous. Metabolic heat (Hm): Energy released within an organism during process of cellular respiration. Metabolic water: Water released during oxidation of organic molecules. Metacommunity: The dominance-diversity curve in neutral theory that characterizes species diversity at the metacommunity equilibrium between rates of speciation and extinction of species. Metalimnion or thermocline: Transition zone in lake between (or a depth zone) between the epilimnion and hypolimnion. A region of rapid temperature decline and increases in water density with depth. Often used synonymously with the term themlocline. Metapopulation: A group of subpopulations of a population living in separate locations with active exchange of individuals among subpopulations. Metastasis: Movement of cancer cells to another location, where new tumors are formed. Methyl mercury: Water soluble organic form of mercury formed by bacteria in aquatic ecosystems from inorganic (insoluble). Micella: Soil particle of clay and humus, carrying electrical charges at the surface. Microbivore: Organism that feed on microbes, especially in the soil and litter. Microclimate: A small-scale variation in climate that differs from the general climate of the area influences the presence and distribution of organisms. Microconsumers: Bacteria and single celled fungi that are part of the decomposer food chain. Microcosm: A small simplified experimental ecosystem in a container explored as an analogy to large ecosystems. Microevolution: Evolution relating chiefly small changes in the frequency of different alleles within a population that occur over time by natural selection. Microflora: Bacteria and certain fungi inhabiting the soil. Microhabitat: The part of the more general habitat utilized frequently by an organism. Micronutrients: Essential nutrients but needed in very minute quantities or trace amounts by plants and animals such as copper, iron and zinc. Contrast with macronutrient. Microparasite: Viruses, bacteria and protozoan characterized by small size, short generation time, and rapid multiplication. Microsatellie: DNA sequence of tandemly repetitive DNA, 10 to100 base pairs long. Mid-oceanic: Ridges undersea areas in which spreading tectonic plates create vents, hot sulfurous springs, and seeps. Midparent: The average of the two parents. Migration: Intentional directional and usually seasonal movement of animals between two regions or habitats; involves periodic departure and return of the same individuals in a population. Mill tailings: Residue from uranium processing plants. Spent uranium ore that is contaminated with radioactivity. Milne models ecotone is a kind of phase transitions. Typical phase transitions involve changes in the state of matter, such as the change of water from a liquid to a solid state as temperature decreases. The change from liquid water to ice involves fundamental changes in the organization of water, including the average distance between water molecules and their distributions. Milpa agriculture: Cut and burn farming. Mimic: An organism whose appearance resembles that of another kind of organism. Mimicry: Resemblance of one species to another or to an object in the environment evolved to mislead predators. Mineral: A chemical element (e.g., gold) or inorganic compound (e.g., iron ore) existing naturally. Mineralization: Microbial breakdown of humus and other organic matter to inorganic form during decomposition. Minimum area: Sum of area of quadrates to be sampled to include all but chance species of a habitat. Minimum known alive (MKA): Mark-recapture method used to estimate the percentage of the total population known to be alive on a particular date. Minimum tillage: Reduced ploughing and cultivating of cropland during growing seasons to help reduce soil erosion and save energy. Also called conservation tillage: Minimum viable: Size of a population, which with a given probability will ensure the existence of the population for a stated period of time. Mire: Marshland typified by an accumulation of peat. Mitosis: Division of a cell nucleus, in which the chromosomes divide and each daughter nucleus ends up with chromosomes genetically the same as parent cells. Mixed strategy: Situation when the optimal solution to a problem involves more than one response. Mixolimnion: Upper water of a chemically stratified lake. Moa: One of a variety of wingless extinct birds from New Zealand related to ostriches, kiwis, emus, and cassowaries. The last moas were killed off many centuries ago by the Polynesians, when they arrived in New Zealand. Mode: The value or item occurring most frequently in a series of observations or statistical data model formulation that mimics a real-world phenomenon. Model: In systems ecology, an abstraction or simplification of a natural phenomenon developed to predict a new phenomenon to provide insights into existing ones, in mimetic associations an organism that is mimicked by another kind of organism. Moder: Type of forest humus stratum in which plant piece and mineral particles form a loose net like structure and held together by a chain of small arthropod droppings. Modular organism: Organism, such as a tree or coral, which is made up of an indeterminate number of repeatable units. Molecular biology: The branch of biology that attempts to know the chemical mechanisms of life. Molecule: Particle consisting of two or more atoms together. The atoms in a molecule that can be of the same element but are usually of different elements. Mollisol: Soil formed by calcification differentiated by collection of calcium carbonate in lower horizons and high organic content in upper horizons. Molly: A small fish of the genus Poecilia (Mollienesia), whose eggs hatch internally so that the young are born alive. They are popular with aquarists and thrive in alkaline water. Monecious plants: Plants in which flowers of both sexes (male flowers that produce pollen and female flowers that bear ovules) are found on the same plant. Monoclimax theory: The idea that all successional sequences led ultimately to one of a few distinctive community types, depending on the climate of the region. Monoculture: Cultivation of one plant species (such as wheat) over a large area. Monogamy (Monogamous species): Mating of an animal with only one member of the opposite sex. Monolayer: Postulated leaf arrangement for shade trees in which leaf shape and pattern achieves maximum light obverse in a narrow vertical distance. Montane: Related to mountains. Moor: A coverlet bog or peat land Mor: Thin, sticky, structureless layer of organic soil material. Mortality (death rate): Number of individuals dies in a population during a given time interval divided by the number alive at the start of the time interval. Motane: Pertaining to mountains. Mouthbrooder: A fish in which the female bears the eggs and young in her mouth to protect them. Mull: A humus rich layer of forested soil consisting of mixed organic and mineral matter. Mull: Crumbly, dark, fertile soil layer. Mullerian mimicry: The mutual resemblance of distasteful organisms that presumably makes it easier for unintelligent predators to learn what patterns to avoid. In Mullarian mimicry complexes, all members are both models and mimics. Multilayer: Postulated leaf arrangement for trees of bright sunlight that allows deep diffusion of light. Multivoltine: An organism that have several generations during a single season. Mutagen: A substance (chemical or physical agent) capable of damaging the genetic material (DNA and chromosomes) or changes in genetic material of living organisms in both germ cells and somatic cells. In other words the agents used for producing mutations are called mutagens. There are two types of mutagens: a) Physical mutagens: i) Ionizing radiation such as -ray, -ray, X-rays and -ray. ii) Nonionizing radiation: ultraviolet (UV) radiation. b) Chemical mutagens such as colchicines, ethylimine, ethyl methane sulphate, acrifluvin, proflavine, acridine orange, acridine yellow, 5-bromouracil etc. Mutant: An individual carrying a mutation. Mutation Theory: Hugo de Vries (1840-1935), a Dutch botanist, proposed mutation theory for evolution. In his book “The Mutation Theory”, he stated that a new species arise by sudden change rather than by gradual processes, is called mutation. According to him, it is mutation, not selection that should be considered as the primary factor of evolution. de Vries’s mutation theory is based on his experimental work on the evening primrose (Oenothera lamarckiana) in 1886. He cultivated these plants in his botanical garden at Amsterdam. He raised the seeds and sown them again and again up to eight generations. Surprisingly he found that in each generation the inheritances of the new parental characters are observed in some of the individuals. He called such sudden hereditary changes “mutation” and believed that some of his mutants produced in a single step were actually new species and established his theory of Mutation in 1901. Mutation may be defined as a random heritable change of genetic material in the gene, and express this change in their phenotypes and organism that possesses such a change is called a mutant. Mutation: An allele that has change into another allele. Also used for major changes in the structure of chromosomes. In general, any damage to the DNA and chromosomes. Mutations in chromosome number: Mutations (Latin word, mutates = change) are permanent changes in genes or chromosomes that can be passed to offspring. Changes in the chromosome number include monosomies (loss of one chrosmosome, 2n-1), trisomies (adding of one chromosome, 2n+1) and polyploidy. Changes in the number of chromosome (an individual or an entire set) are known as chromosomal mutations. Mutualisms: Relationship between two or more species in which the growth and survival of both populations benefit to both partners. Mutualisms are widespread, important and found virtually in all plants. Terrestrial plants are involved with a rich variety of mutualisms with animals because vascular plants depend upon animals for dispersal of pollen, fruits and seeds. Mycelium: Mass of hyphae that make up the vegetative part of a fungus. Mycorrhizae: Fungi that form a mutualistic relationship or associations with the higher plants roots, aiding them in the uptake of nutrients from the soil. N Naked mole rats (Sand puppies): Heterocephalus glaber (Bathyergidae), occur in northeast Africa. These burrowing almost hairless rodents live in colonies organized much like those of social insects. Nannoplankton: The very smallest plankton that passes through most collecting nets includes protozoa as well as small phtoplankters. Narrow-spectrum pesticide: A chemical agent effective in controlling a small number of pests. Natal group: Collection of individuals of the same species into which an individual is born. Natal territory: Territory, where an individual was born. Natality: Ability of a population to increase by reproduction. It is the production of new individuals in a population (birth rate). National parks: A relatively large area of land set side (under some Act); where flora and fauna are permanently dedicated for public enjoyment, education and inspiration. National parks are the backbone of efforts to save biodiversity. They need to be strengthened to embrace the full range of ecosystems and their species. It is needed to keep protected so that their species may remain conserved. Visitors are allowed to enter, under special conditions such as inspirational, cultural and re-creative purposes, which contain a natural landscape of great beauty Native species: Plants, animals, fungi and microorganisms that occur naturally in a given area or region. Natural capital: Benefits and services supplied to human societies by natural ecosystems. Natural erosion: Loss of soil occurring at a slow rate but not caused by human activities. A natural event in all terrestrial ecosystems. Natural gas: Gaseous fuel containing 50%-90% methane and lesser amounts of other burnable organic gases such as propane and butane. Natural hazards: Dangers that result from normal meteorological atmospheric, oceanic, biological, and geological phenomena. Natural history: The study of how organisms in a particular area are influenced by factors such as climate, soils, predators, competitors, and evolutionary history, involving field observations rather than carefully controlled experimentation or statistical analyses of patterns. Natural resource: Resource. Natural selection: Evolutionary process involving differential reproduction and survival of individuals that results in elimination of maladaptive traits from a population and some types of individuals being represented more frequently than others in the next generation; proposed by Charles Darwin as the primary mechanism driving evolution. In other words it is a process in which slight variations in organisms (adaptations) are preserved if they are useful and help the organism to better respond to its environment. Darwin defined the natural selection as the preservation in nature of favourable variations and destructions of those, which are injurious (Darwin, 1859). Darwin's model (Natural selection) of evolution is known as ‘the survival of the fittest’. Nature reserve: Area created as a shelter for threatened species or ecosystems. Nectar food chain: Food chain originating from the nectar of flowering plants, commonly dependent on insects and other animals for pollination. Nectivore: An organism that feeds on nectar. Negative feedback: Control mechanism present in the ecosystem and in all organisms. Information in the form of chemical, physical and biological agents influences causing them to shut down or reduce their activity. Negative phototaxis: Movement of an organism away from light. Neighbourhood stability: Ability to withstand perturbations of small magnitude and to be affected; compare with global stability. Nekton: Aquatic animals that that can swim and can control their position by swimming to overcome currents, such as fish, squid, sea turtles, and great whales and other the plankton. neo-Lamarckism: According to neo-Lamarckism habits and environments cause evolution. It provides the simplest and the most direct mechanism for evolution. NeoLamarckism became strong among the paleontologists. Neon tetra: Hyphessobrycon innesi (Characidae), a small, slender, brilliantly colored fish that lives in acid fresh waters in South America; it is popular with aquarists. Neopilina: It is believed that Neopilina (Class- Monoplacophora, Order- Tryblidioidea, and Family- Neopilinidae) lived from the early Cambrian to the middle Devonian period and was extinct since 350 million years ago. But recently (around 1960) it is known that Neopilina galathea, N. ewingi and N. valeronis still exist in trench of Costa Rica and the Cedoras trench of Lower California . Neoplina looks practically identical with its ancestor fossils. Neretic: Refers to a region of marine environments embracing where land masses extend outward as a continental shelf. Nertic zone: Life zone in the ocean near shore (where the ocean is about 200 m deep), encompassing the shallow waters over the continental shelves. Net aboveground production: Buildup of biomass in aboveground parts of plants over a given period of time Net belowground production: Accumulation of biomass in roots rhizome and the like. Net community: Productivity rate of storage of organic matter in an ecosystem that is not used by heterotrophs during the period of measurement (usually a growing season or a year) Net energy: Energy remaining after metabolic losses that is available for growth and reproduction; yield beyond the energy cost of supporting the alteration system. Net migration: Number of immigrants minus the number of emigrants. It can be expressed as a rate by determining immigration and emigration rates. Net primary production: The amount of energy left over autotrophs (photosynthesizing plants) has met their own energetic needs (gross primary production minus respiration by primary reducers). The amount of energy available to the consumers in an ecosystem. Net primary productivity (NPP): Gross primary productivity (the total amount of energy that plants produce) minus the energy plants use during cellular respiration (NPP=GPP-R). Net production: Accumulation of total biomass over a given period after respiration is deducted from gross production in plants and from assimilated energy in consumer organisms deducted from gross production. Net reproductive rate (R0): The average number of offspring produced by an individual in a population. Net useful energy production: Amount of useful energy, extracted from an energy system. Neuston: Organisms supported on water surface. Neutral equilibrium: The particular state of a system that has no forces acting upon. Neutral theory: Extension of the theory of island biogeography, proposed by Stephen P. Hubbell in 2001, in which all species are treated as if they possess the same per capita rates of birth, death, dispersal, and speciation. Neutralism: Association between two species in which neither population is affected by association with the other. Neutralists: Geneticists who believe that most naturally occurring variation in enzymes does not affect their functioning enough for selection to distinguish among them. Neutrality controversy: The argument between selections and neutralists over the significance of the large amount of genetically based variation in enzymes that occurs in natural population. Neutrophilus: Pertains to plants not restricted to high calcium or to acidic soils. Niche assembly theory: Hypothesis that ecological communities are equilibrium groupings of competing species, coexisting as each species is the mainly effective competitor in its own niche. Niche breadth: Range of a single niche dimension occupied by a population. Niche overlap: Overlap or sharing of niche space by two or more species. Niche space: Environmental parameters defining a niche, or the resource flux required for an individual to survive and reproduce. Niche theory: A body of mathematical competition theory in which niche overlap is the basis of competition. Niche: Also called an ecological niche. An organism's place in the ecosystem: where it lives, what it consumes, what consumes it and how it interacts with all biotic and abiotic factors. It is the way in which an organism obtains its resources; the ‘occupation’ of an organism as contrasted with its ‘address’ or ‘habitat’. Niche-packing: Conceptual process of community building with final species number set by maximum possible interspecific competition. Nidicolous: Young that fed in nest. Nidifugous: Young that leave the nest as soon as hatched. Nitrate (NO3-): Inorganic anion containing three oxygen atoms and one nitrogen atom linked by covalent bonds. Nitrification: Production of nitrites and nitrates as microorganisms break down or organic compounds that contain nitrogen to forms usable by organisms. Nitrifying bacteria: Bacteria that oxidize ammonium to nitrate and/or nitrate ions. Nitrite (NO2-): Inorganic anion containing two oxygen atoms and one nitrogen atom. This NO2combines with hemoglobin and may cause serious health impairment and death in children. Nitrogen cycle: The cycling of nitrogen between organisms and the environment among the atmosphere, soil, and living matter; movement of nitrogen (N) among the atmosphere, biosphere, and hydrosphere, including transformations between different chemical forms. Nitrogen fixation: Conversion of atmospheric nitrogen (a gas) into nitrate and ammonium ions (inorganic form) by certain prokaryotes such as Rizobium, which can be used by leguminous plants. Nitrogen oxides (NO): Nitric oxide (NO) and nitrogen dioxide (NO2), produced during combustion when atmospheric nitrogen (N2) combines with oxygen. It can be converted into nitric acid (HNO3). But all are harmful to humans and other organisms. Nitrogenase: Enzyme responsible for nitrogen fixation. Noise: An unwanted or unpleasant sound. Non point source (of pollution): Diffuse source of pollution such as an eroding field, urban and suburban lands, and forests. It is an opposite term of point source. Nonattainment area: Region that violates EPA air pollution standards. Nonequilibrial theory: Theories of ecological systems that do not assume equilibrium conditions. Non-equilibrium theory of species coexistence: Idea that competition between species is relatively unimportant in shaping communities. Nonevolutionary responses: Adaptive changes made by the organism in response to changes in the environment. Nonparametric statistics: Statistical tests that do not require a normal or random pattern of distribution but can be carried out on qualitative or ranked information. Nonreductible properties: Properties of the whole that is not reducible to the sum of the properties of the parts. Nonregulators: Animals that exert no physiological or behavioral control over their body temperature, such as animals that burrow in soil and very small invertebrates. Nonrenewable resource: A resource that is used up over time and is not replaced or regenerated naturally within a reasonable period (fossil, fuel, mineral). Nonstabilizing factors: Influences on population growth that are independent of the size of the population. Noosphere: A system dominated or managed by the human mind as anticipated by the Russian scientist V.I. Vemadskij in 1945. Normality data: Conformation to a bell-shaped curve of the normal probability distribution. Normalizing selection: Selection favouring individuals in the middle of the distribution of phenotypes in a population and disfavoring the extremes; often called stabilizing selection. Novel mutation: A change to an allele that is not already in the population. Nuclear fall: Hypothesis suggesting that the effects on the earth’s climate of dust and smoke released in nuclear explosions would be more temporary and less severe than predicted by the nuclear winter hypothesis. It is an opposite term of nuclear winter. Nuclear fission: Splitting of an atomic nucleus when neutrons strike the nucleus. Products are two or more smaller nuclei, neutrons (which can cause further fission reactions), and an enormous amount of heat and radiation energy release from this fission. Nuclear fusion: Joining of two small atomic nuclei (such as hydrogen and deuterium) to form a new and larger nucleus (such as helium) accompanied by an enormous release of energy. It is a source of light and heat from the sun. Nuclear power (or energy): Energy from the fission or fusion of atomic nuclei. Nuclear winter: Hypothesis suggesting that dust from nuclear explosions and smoke from burning cities would reduce solar radiation, resulting in a dramatic decrease in global temperature. . It is an opposite term of nuclear fall. Nucleation: Birth of an ice crystal around a small impurity. Nucleotide: The basic building blocks of deoxyribonucleic acids (DNA), which made up of a five carbon sugar (deoxyribose or ribose): A phosphate group and a nitrogenous base (guanine, cytosine, adenine or thymine. Null hypothesis: The hypothesis that the effect one is looking for has not occurred; statement of no difference by between sets of values formulated for statistical testing. Numerical response: Change in the density of a predator population in response to increased prey density; the reaction of the predator population to the availability of prey. Nutrient cycle: Same as biogeochemical cycle. Nutrient cycle: The mostly closed pathways followed by nutrients as they move through ecosystems from absorption by organisms to release by decomposition. Nutrient cycling: The use, transformation, movement, and reuse of nutrients in ecosystems, It is a biogeochemical pathway in which an element or nutrient moves through ecosystems from absorption by organisms to release by decomposers (bacteria and fungi), to be taken up by producers and recycled through the trophic levels once again Nutrient retentiveness: The tendency of an ecosystem to retain a source of energy nutrients. Nutrient spiraling: It is a representation of nutrient dynamics in streams, because of downpour displacement of organisms and materials in the streams. Nutrient spiraling: Model of nutrient dynamics in a stream or river that, as the down stream displacement of organism or materials, are better represented by a spiral than a cycle. Nutrient: A substance essential for the normal growth, development, maintenance, reproduction, health, vitality and other activity of an organism. Often it is used in the more limited sense of inorganic nutrients taken up by plants from air or water. O O (organic)-horizon: The most superficial soil layer containing substantial amounts of organic matter including whole leaves, twigs, other plant parts, and highly fragmented organic matter. Obligate anaerobe: Organism that cannot utilize oxygen, indeed which may be poisoned by it. Obligate mutualism: A mutualistic relationship in which species is dependent upon the relationship that they cannot live in its absence. Obligate predator (or parasite): Predator that is restricted to eating a single species of prey. Oceanic zone: The open ocean beyond the continental shelf with water depths generally greater than 200 m. Oceanography: The branch of ecology dealing with the biology, chemistry, geology, and physics of the ocean. Oestrus: Condition of a female mammal when she is prepared to mate. Humans are not said to show oestrus because women are sexually receptive throughout their reproductive cycle. Off-road vehicle (ORV): Any vehicle used cross country. especially in a recreational capacity such as four wheel drive vehicles, dune buggies, all terrain vehicles, snowmobiles, and trail bikes. Oil shale: A fine-grained sedimentary rock called marlstone and containing an organic substance known as kerogen. When heated, it gives off shale, oil that is much like crude oil. Old growth forest: Forest that has not been cut for decades nor troubled by humans for hundreds of years. Oliogotrophic (Infertile): Term applied to a body of water (or lakes) low or deficient in plant nutrients, abundant oxygen, and low primary production Ombrotrophic: A condition in bogs or mires in which water is highly deficient in mineral salts and has a low PH. Omnivore: A heterotrophic organism that consumes (feeds) a wide range of food items, usually including both animal and plant matter. Oparin theory (chemical evolution): Oparin theory argued that life was evolved from organic chemicals (H2O, CH4, and NH3) in the primitive seas at the time when earth atmosphere was free from Oxygen. The first cell (life) was formed by a series of chance actions. It has been declared that from this simpler organism, all species of living organisms have been evolved through gradual changes over vast period of time. Even human beings, like all other plants and animals have been evolved from this simpler organism. Open system: A system that freely exchanges energy with the environment. Example: any living organism with closed system. Open-community concept: The idea, advocated by H. A. Gleason and R. H. Whittaker. They opine that communities are the local expression of the independent, geographic distributions of species. Operational sex ratio: A ratio of sexually prepared males to fertilizable females. Opportunistic species: Organisms able to utilize temporary habitats or conditions. Opportunity costs: Costs of lost money-making opportunities (and potentially higher income) incurred when it make a decision to invest money in a particular way. Optimal defense: A theory that opine secondary compounds are allocated to defense in a way that minimizes cost and maximizes inclusive fitness. Optimal foraging theory: Theory that attempts to model how organisms feed as an optimizing process, a process that maximizes or minimize some quantity, such as energy, intake or predation risk. Evolutionary ecologies predict that if organisms have limited access to energy, then natural selection is likely to favor individuals within a population that are more effective at acquiring energy. This prediction spawned an area of ecological inquiry called optimal foraging theory. Optimal foraging theory assumes that energy supplies are limited and organisms cannot simultaneously maximize all of life’s functions; for examples, allocation of energy to one function, such as growth or reproduction, reduces the amount of energy available to other functions such as defense. Optimal foraging: Tendency of animals to harvest food efficiently to select food sizes or food patches that will result in maximum food intake for energy expended. Optimization: A process that maximizes or minimizes some quantity. Optimum carrying capacity (k0): A lower level of population density at carrying capacity conditions than the maximum carrying capacity (km), which can be sustained in a particular habitat without ‘living on the edge’ relative to resources such as food and space. Optimum sustained yield: Level or amount of harvest that can be removed from a population and that will result in the greatest yield that can be sustained indefinitely. Optimum yield: Amount of material that can be removed from a population, which will result in production of maximum amount of biomass on a continued yield basis. Opuntia: Prickly pear cactus, which became a plague when introduced into Australia Order (taxonomic): A major category above the family and below the phylum. Butter flies and moths belong to the order Lepidoptera, wolves and lions to the order Carnivora. Ordination: Process by which plant or animal communities are ordered along a gradient. It is an investigation of the distribution of species along environmental gradients. Ordovician: Second oldest period of the Paleozoic some 510 to 440 million years ago and oceanic invertebrates plentiful in this period. Ore deposit: A valuable mineral located in high concentration in a given region. Ore: Rock bearing important minerals for example, uranium ore. Organic diversity: The variety of plants, animals and microorganisms that inhabit Earth. Frequently restricted to the diversity of species. Diversity within species is also significant ecologically and evolutionarily. Organic farming: Agricultural system in which natural fertilizers (manure and crop residues), crop rotation, contour planting biological insect control measures, and other techniques are used to ensure soil fertility, erosion control, and pest control. Organic fertilizer: Material such as plant and animal wastes added to cropland and pastures to improve soil. Provides valuable soil nutrients and increases the organic content of soil (thus increasing moisture content). Organism: An individual unit constituted to carry on the activities of life. Organismic phase: The part of the nutrient cycle in which nutrients are located in organisms— plants, animals, bacteria, fungi, or others. Origin of Species: ‘The Origin of Species’ is world revolutionary book and an epochmaking work is written by Charles Darwin in 1859. Like this important volume of biology has ever been written. ‘The Origin of Species’ has an immense importance in biology especially in evolutionary science. In this book Darwin explained his theory natural selection. Origin: In soils refers to nature of the parent materials and to whether the soil is developed at the source of the parent materials or at distant site. Orogeny: Mountain building. Orthodox seed: Seed that can be dried to moisture levels between 4 and 6 percent and kept at low temperature. Oscillation: Regular fluctuation in a fixed cycle above or below some set point. Osmosis: Movement of water molecules down its concentration gradient across a differentially permeable membrane in response to a concentration or pressure gradient. Outbreeding: Production of offspring by mating in which adults mate with distantly related often than expected by chance. Out-migration: Movement of people out of a state or region within a country to set up residence elsewhere in that country. Output approach: A method of solving an environmental problem by controlling the outputs. For example, burning trash reduces the land requirements for solid waste disposal. It is a control devices reduce air and water pollution. Overgrazing: Excessive consumption of producer organisms (plants) by grazers such as deer, rabbits, and domestic livestock; a indication that the ecosystem is out of balance. Overpopulation: A condition resulting when the number of organisms in an ecosystem exceeds its ability to assimilate wastes and provide resources. It creates physical and mental stress on a species as a result of competition for limited resources and deterioration of the environment. Overrepresentation: Take too numerous in a pollen diagram because of large local source of pollen. Overturn: Vertical mixing of layers in a body of water brought about by seasonal changes in temperature. Oxidants: Oxidizing chemicals (for example, ozone) found in the atmosphere. Oxidation: An energy-yielding chemical reaction in which atoms or molecules lose electrons. Oxisol: Soil created under humid semitropical and tropical conditions characterized by silicates and hydrous oxides, clays, residual, quartz. This soil is lack in bases and low plant nutrients created by the process of laterization. Oxygen-demanding wastes: Organic wastes that’s broken down in water by aerobic bacteria. An aerobic breakdown causes the oxygen levels to drop. Ozone (O3): Inorganic molecule found in the atmosphere, where it is a pollutant because of its harmful effects on living tissue and rubber. Ozone also found in the stratosphere, where it helps screen ultraviolet light. It is used in some advanced sewage treatment plants. Ozone layer: Thin layer of ozone molecules in the stratosphere. This layer absorbs ultraviolet light and converts it to infrared radiation. Ozone layer effectively screens out 99% of the ultraviolet light. P Paca: Agouti paca, a large rodent, which is more than 2ft long and found in the rain forests of tropical America. Pair wise co-evolution: Co-evolution in which interaction between organisms in adequately close and each species is the prime actor in the evolution of the other. Paleoecology: Study of ecology of past populations. In other words it is the study of the relationships of primordial (past) flora and fauna to their environment by means of the fossil record. To geologists it means reconstructing past environments from assumptions about animals and plants found as fossil. To biologists it means reconstructing niches of the past from reconstructions of past environments. Paleolimnology: Studies of lake ecosystems of the past from evidence preserved in lake mud. Paleozoic: Geological era of 620-230 million years ago, initial with the Cambrian period and finishing with the Permian, during which land plants, insects, amphibians and the first reptiles evolved. Palynology: Study of pollen and spores. Pan chronic species: Blue green algae, Ferro-bacteria, sponge, mollusks, opossum, horse shoe crab, Limulus etc. known as pan chronic species. According to evolutionists these species have unchanged till now. Pangaea: The giant single continent that existed prior to some 200 million years ago. But after 200 million years Pangaea gradually broke up and plate tectonics began to generate the configuration of continents that exist today. Pangenesis theory of Darwin: In 1868, Darwin has given his famous theory called “Pangenesis” to explain how acquired variations may be transmitted to the offspring. He assumed that all the organs, perhaps the entire cell, in the body of any animal produce miniatures of themselves. These miniatures called gemmules (or pangenes), which are minute particles, carry information about the organs. The pangenes traveling through the blood stream will ultimately reach the gametes, so each of gametes will have pangenes for each of different organs. After zygote formation, the pangenes tend to form the same organs from which these pangenes are produced. In the year 1875, Galton made pangenesis hypothesis indefensible by presenting several experimental proofs. Darwin himself was very cool reception of this theory during his lifetime. Paradigm: A major theoretical construct that is central to a field of stuffy. For example, the theory of evolution and the structure of DNA are two paradigms that are central to biological science. Paradise fishes: It is the mainly usual cleaner wrasse Labroides dimidiatus. Paradox: Statement apparently conflicting with common sense but actually well founded or reasonable. Paramecium: A genus of protozoa (single celled organisms) common in pond water, sometimes called ‘slipper animalcules’. Parametric statistics: Statistical checks that need quantitive data or observations based on a normal or random pattern of distribution. Parapatric: Living in adjacent regions but not partly covering by much more than the dispersal range of an individual in its lifetime. Parasite: An organism that lives is or on another organism, called the host, deriving benefits from it, without killing it in at once (if ever). Parasites typically reduce the fitness of the host, but do not generally kill it. They are generally much smaller than their prey and may live inside them on their surface or (in the case of brood parasites) in the same nest with the host's young. Parasitism: Relationship between two species in which one population (the parasite) benefits but the other (the host) is harmed (although not usually killed directly). Parasitoid: Insect lava that kills its host, generally another insect, by consuming completely the host soft tissue before goes to metamorphosis into an adult. Parasitoids are functionally equivalent to predators. Parasitology: The branch of science that dealing with small organisms (parasites) living on or in other organisms (hosts), in spite of whether the result of the parasite on the host is negative, positive, or neutral. Parataxonomists: Field-trained biodiversity collection and inventory specialists recruited from local areas. Parental investments: The resources individuals dedicate to offspring Particulates: Solid particles (dust, pollen, soot) or water droplets in the atmosphere. Pascal: A unit of pressure; 106 Pascals or 1 Mega Pascal (1 MPa) equal 9.87 atm. Passive solar: Capture and retention of the suns energy within a building through south facing windows and some form of heat storage in the building (brick or cement floors and walls). It is an opposite term of active solar. Patent: A government grant of temporary monopoly rights on new processes or products. Pathogen: Any organism that induces disease, a debilitating condition, in their hosts; common pathogens include viruses, bacteria, and protozoans. Pattern diversity: Biotic diversity based on zonation, stratification, periodicity, roughness, or other criterion. Pattern-climax theory: The hypothesis that succession reaches a wide variety of nondiscrete climax communities depending on local climate, soil, slope, grazing pressure and so on. PCBs: Polychlorinated biphenyls. Peat: Unfruitful material consisting of undecomposed and only slightly decomposed organic matter under conditions of too much moisture. Pecking order: Supremacy hierarchy Ped: Soil particles that held together in clusters of various sizes Pedalfer: Podzolic soil controls a layer of iron accumulation that holds up free circulation of air and water. Pedology: Study of soil in all its aspects. Pedon: Smallest describable patch of a soil series. Peferred temperature: Range of temperatures within which poikilotherms function most efficiently Pelagic zone: Life zone of the ocean consisting of the open waters beyond the continental shelf. Pelagic: A term referring to marine life zones or organisms above bottom; for instance, tuna is a pelagic fish that live in the epipelagic zone of the oceans. Peneplain: Flat dissected surface from erosion by an ancient river system. Pepered moth: Biston betularia in the family Lymantridae. Peppered moth: White-coloured moth B. betularia time to time produces a black moth B. carbonaria. Near manufacturing center of Manchester, this melanic form of the species peppered moth B. carbonaria was discovered for first time in 1850. White coloured moth Biston betularia was not changed to black coloured B. carbonaria due to pollution; rather the reality is that the abundance (number) of black moth B. carbonaria is increasing and white moth B. betularia is decreasing in industrial areas of England day by day due to predation by birds. Attractively, the use of pollution control (in 1952) in British manufacturing industries has produced clean air, the background of tree trunk is again becoming lighter and the white moth is increasing now and the dark moth is decreasing. Per capita rate of increase: Usually symbolized as r, equals per capita birthrate minus per capita death rate: r = b-d. Perennial: A plant that that lives longer than 1 year (for example, rose and bushes). Perfect flower: Hermaphroditic flower. Periphyton in freshwater ecosystems organisms attached to natural substrates, such as submerged plant stems and leaves, in the littoral or benthic zones of a lake. Its synonym is Aufuuchs. Perissodactyl: 1-toed ungulate animal (e.g., horse). Permafrost: Permanently frozen ground found in the tundra biome. Permanent threshold shift: Loss of hearing after continued exposure noise. It is an opposite term of temporary threshold shift. Permanent wilting point: Point at which water potential in the soil and conductivity assume such low values that the plant is unable to extract adequate water to survive and wilts permanently. Permian: Most recent period of the Paleozoic about 280-23 million yeas ago; supremacy of reptiles; rise of modern insects and gymnosperm plants. Perturbation: Another word for disturbance; borrowed from physics to suggest an event that alters the state of or direction of change in a system. Perturbation-dependent succession: Succession depending on allogenic, recurrent perturbations, such as fire or storms Pesticide residues: The toxicity of a pesticidal residue varies low to very high on a treated harvest crop, soil, wildlife, and environment; and it is expressed in terms of ppm (active ingredient). Pesticide: A general term referring to a chemical, physical, or biological agent that kills organisms we classify as pests, such as and rodents. Pesticide also called biocide. Petroleum: A viscous liquid containing numerous burnable hydrocarbons. It is distilled into a variety of useful fuels (fuel oil, and diesel) and petrochemicals (chemicals that can be used as a chemical feedstock for the production of drugs, and other substances). pH: Measure of acidity on a scale from 0 to 14, with pH 7 is neutral and being numbers greater than 7 being basic, and number less being acidic. Phagioclimax: Vegetation type preserved as climax over a long time of time by continued human activity. Phagotrophs (macroconsumers): Heterotrophic organisms that consume other organisms or particular organic mater. Phanerophyte: Perennial buds of trees, shrubs, and vines carried high up in the air Phase transition: A change in the state of matter such as from a liquid state to a solid state or from a solid to a gas; involves in the organization of molecules and their kinetic state. Phenology: The study of the relationship between climate and the timing of ecological events (i.e. study of seasonal changes in plant and animal life and the relationship changes to weather and climate) such as the date of arrival of migratory birds on their wintering grounds, the timing of spring plankton blooms, or the onset and ending of leaf fall in a deciduous forest. Phenotype: Physical appearance and behavior or characteristic of an organism as determined by genetic constitution in a given environment. It is an opposite term of genotype. Phenotypic plasticity: Capability to change from under different environmental circumstances Pheromone: Chemical substance secreted by insects for communication with other members of their species. Sex-attractant pheromones released into the atmosphere small quantity by female insects attract males at breeding time. It can be used in pest control through pheromone traps and confusion technique. Traps containing pheromones to attract insect pest. These traps may be used to pinpoint the emergence of insects, along conventional pesticides to be used in moderations. Philopatry: A term, which means literally “love of place,” used to describe the tendency of some organisms to remain in the same area throughout their lives; or returning to the place of birth to breed also called philopatry. Phoresy: Dispersal of communal group by host organism. Phosphorus cycle: Movement of phosphorus (P) among the lithosphere (the dominant reservoir), hydrosphere, and biosphere, including the transformations between its different chemical forms Phosphorus: An element essential to living organism because of its role in energy metabolism. Photic zone: Lighted water column of a lake or ocean occupied by plankton. Photoautotroph: An organism that utilizes sunlight as its primary energy source for the synthesis of organic compounds. Photochemical oxidants: Ozone and a variety of oxygenated organic compounds produced during sunlight, hydrocarbons, and nitrogen oxides react in the atmosphere. Photochemical reaction: A chemical reaction that occurs in the atmosphere involving sunlight or heat, pollutants, and some times natural atmospheric chemicals. Photochemical smog: A complex mixture of photochemical oxidants and nitrogen oxides. Usually it has a brownish-orange color. Photochemical: Fog reaction of hydrocarbons with molecules of nitrogen oxide in the presence of ultraviolet radiation in sunlight, producing complex organic molecules of peroxyacetyl nitrates (PAN), resulting in atmospheric smog. Photon flux density: The number of photons of light striking a square meter surface each second. Photoperiod: Response of plants and animals to day-length period (in relative duration of light and dark) or signal by which organism times their seasonal activities (e.g., a chrysanthemum blooming under short days and long nights). Photophosphorylation: Production of ATP from ADP and inorganic phosphorus using light energy in photosynthesis. Photorespiration: Respiration that occurs in light in C3 plants and is not joined to oxidative phosphorylation and does not generate ATP; a wasteful process declining photosynthetic efficiency Photosynthesis: The process by which green plants, algae, or bacteria absorb light and synthesis carbohydrates from carbon dioxide and water by chlorophyll using light as energy and releasing oxygen as a by-product. Green plant transfer their energy to electrons and the energy carried by these electrons is used to synthesize ATP and NADPH, which in turn serve as donors of electrons and energy for the synthesis of sugars. So, it is a two-part process involving (1) the capture of sunlight and its conversion into cellular energy and (2) the production of organic molecules such as glucose and amino acids from carbon dioxide, water, and energy from the sun. Photosynthetic action spectrum: Graph of how fast 1 cm2 of leaf photosynthesizes as a function of the color (wavelength) of light shining on it. Photosynthetic: A term describing organisms capable of photosynthesis. Photosynthetically active radiation (PAR): A wavelengths of light between 400 and 700 mm that photosynthetic organisms use as a source of energy. Photovolataic cell: Thin wafer of silicon or other material that emits electrons when struck by sunlight, thus generating current. It is also known as solar cell. Phreatic zone: The area or the region of a stream containing groundwater below the hyporheic zone. is called the phreatic zone. Phreatophyte: Type of plant that usually obtains its water supply from zone of ground-water. Phycobillisomes: Colored pigments of algae that are adaptations to increase light absorption in dim light. Phycosphere: Corona of bacteria that encloses living algal cells in the marine environment. Phyletic evolution: Change within an evolutionary line. Phylogenetic tree: A treelike diagram showing the time of dividing of various evolutionary lines and sometimes expressing their degree of divergence. It is a graphic representation of group’s phylogeny. Phylogeny: The evolutionary history of a group of organism. Phylogeography: The study of the models of speciation as fixed in biogeography landscapes. Phylum: In taxonomy, a high-level category just beneath the kingdom and above the class; a group or related, similar class. Physiognomic: Refers to shape, structure or form. Physiognomy: External appearance of the landscape. Physiological ecology: The branch of ecology dealing with the physiological performance of organisms in relation to their environment Physiological longevity: Maximum life span of an individual in a population under optimum environmental conditions that is in a population under given environmental situations. Physiological natality: Greatest number of young that a female is able of reproducing physiologically during her lifetime. Physiologicalecology: The branch of ecology that concerned with the dynamic relationship of individuals to their physical environments and resources. Phytolith: Silica concretion within a plant cell. Phytophthora infestans: Potato blight, the fungus responsible for the Irish potato famine in the nineteenth century. Phytoplankton: microscopic photosynthetic tiny floating plant life in aquatic ecosystems; and drift with the currents in the open sea or in lakes. Phytoplankton also known as planktonic plants. Phytoplanter: Individual plant of the plankton. Pin frame: Mechanism used for gaining a quantitative estimate of vegetative cover. Pioneer community: The first community that become established in a once lifeless environment during primary succession. Pioneer species: Plants that are primary attackers of disturbed sites or near the beginning seral stages of succession. Pioneer stage: Initial seral stage of a sere characterized by early successional plant species (typically annuals). Piscivores: A predator that eats fish such as pike and largemouth bass that feed on other fish. Pistil: Female organ of a flower. Pit viper: A poisonous snake of the Western Hemisphere. It includes the rattle snake, cottonmouth, bushmaster, and fer-de-lance. Pitch (or frequency): Measure of the frequency of a sound in cycles per second (hertz, Hz). Plaenotology: The study of fossil organisms. Plankter: Organism of the plankton. Plankton: Small floating or weakly swimming plants and animals in freshwater; so small as to be carried with the currents. Planted corridor: A strip of vegetation cover by humans for economic or ecological uses (such as a strip of trees planted as a windbreak). Plasmodium: The genus of protozoa that cause malaria. Four species infect human such as Plasmodium malaria, P. falciparum, P. vivax and P. ovale. All species causing somewhat different symptoms in human. Plate tectonics: The transfer of crystal plates of Earth carrying with them continents that as a result of drifts. Pleistocene: Geological epoch lengthening from about 2 million to 10,000 years ago, differentiated by frequent glaciers; the ice age. Pleuston: Organisms suspended from water surface. Pluvial: Time of increased rainfall. Pmax: Maximum rate of photosynthesis for a particular plant species growing under ideal physical conditions. Pneumoconiosis (black lung): A debilitating lung disease cause by prolonged inhalation of coal and other mineral dusts; resulting in a decreased elasticity and gradual breakdown of alveoli in the lungs. Eventually leads to death. Pneumotophore: Upright respiratory root that project above waterlogged soils; typical of hairless cypress and mangroves. Podzolization: Soil forming method, resulting from acid leaching of the A- horizon and accumulation of iron, aluminum, silica, and clays in lower horizon. Poikilohydric: Internal water state matches that of the environment. Poikilotherm: Organism whose body temperature varies directly with the temperature of its environment temperatures; commonly called cold-blooded. Poiklilothermy: Variation of body temperature with external conditions Point diversity: In very small samples. Point of inflection: The point on a sigmoid (S-shaped) growth curve where the growth rate is maximal. Point source (of pollution): Easily discernible source of pollution such as a factory. Pollen influx: Pollen grains deposited per unit area in unit time. Pollen spectrum: Histogram of pollen percentages. Pollen zone: Section of pollen diagram in which spectra remain similar and which can be distinguished from neighboring zones. Pollution: Any physical, chemical, or biological alternation of air, water, or land that is harmful to living organisms. Pollution: Frequently defined as resources misplaced. Polyandry: A mating system in which one female mates with several males. Polychlorinated biphenyls (PCBs): Group of at least 50 organic compounds that used for many years as insulation equipment. These groups of organic compounds are capable of biological magnification; disrupts reproduction in gulls and possibly other organisms. Polyclimax concept: Theory that the final seral stage of succession is controlled by one of several local environmental forces or conditions such as soil, fire, or climate. Polygamy: Attainment by an individual of two or more mates, none of which is mated to other individuals. Polygynous species: The species in which a single male mates with more than one female during a breeding season. Polygyny: A mating system in which one male mates with several females Polymorphic locus: A locus, or gene, that occurs as more than one allele, each of which synthesizes a different allozyme. Polymorphism: The presence in a population of more than one distinct form of individuals in a population. Polyploid: Having three or more times the haploid number of chromosomes. Polyploidy: Polyploidy generally arises following hybridization .Polyploidy also refers collectively to all natural and induced change in chromosome numbers. So, when an organism possessed more than two sets of chromosome, this condition is called polyploidy. Polyploidy may arise through somatic mutation and nondisjunction of entire set of chromosomes. Polytypic species: Species that contain two or more sub species are called polytypic species. Population biology: The subdiscipline of biology that deals with population of organisms. Population control: In human populations, all methods of reducing birth rate, primarily through pregnancy prevention and abortion. In an ecological sense, regulation of population size by a myriad of abiotic and biotic factors. Population crash (dieback): Sudden decrease in population that results when an organism exceeds the carrying capacity of its environment. Population density: Number of individuals in a population within defined unit of space. Population dynamics: The study of constancy and change in the number and density of populations in time and space. Population ecology: The branch of ecology that deals with the relationship of a particular population or species with its environment. Population genetics: Study of change in the frequencies of genes and genotypes within a population. Population histogram: Graphical representation of population by age and sex. Population regulation: Mechanisms (or reason) within a population that cause its density to decrease when high (above its carrying capacity) and to increase when the density is low (below its carrying capacity). Population: A group of individuals having same species (inhabiting a specific area) and live within a specified region or habitat at a given time. Collection of organisms of the same species also known as population. Positive feedback: Control mechanism in ecosystems and organisms in which information influences some process, causing it to increase. Positive phototaxis: Movement of an organism toward light. Poster colors: Bright colors of many reef fishes once thought to be territorial warnings. Potential energy: Energy available to do work due to position or chemical bonding. Potential energy also known as stored energy. Potential evapotranspiration: Amount of water that would be transpired under continually optimal conditions of soil moisture and plant cover. Power: Probability of detecting a significant treatment effect when in fact there is one. PPm: Parts per million, a measure of concentration, the same as micrograms per milliliter or milligrams per liter. Precambian: Earliest and longest of the geological time periods some 4600 and 570 million years ago. Blue-green algae and fungi were emerged in this era. Precautionary principle: Encourages humankind to take action before effects are seen. Precocial: Young birds, who’s young are able to move about, eyes open and feed upon hatching; also young mammals born with eyes open and able to follow their mother after birth (for example, fawn deer, calves) Predation: Relationship between two species in which one population serves as a food source for the other; a relationship whereby a predator kills its prey. Predator control: A predator-prey interaction in which the predator controls the population’s size; that is, in which the predator population is the limiting factor for the prey population size. Predator satiation: A defensive tactic in which prey reduce their individual probability of being eaten by occurring at very high densities; predators can only capture and eat so many prey and so become satiated when prey are at very high densities. Predator: A heterotrophic organism, usually an animal that actively hunts, kills and eats other organisms for food. Presbycusis: Loss of hearing with age through natural deterioration of the organ of corti; the sound receptor in the ear. Prescribed burning: Fires handled by humankind that favors particular organisms and ecosystems, such as grasslands and longleaf pines. Prey: Living organisms that serves as a food source for another organism (e.g., deer) or kill by a predator is called prey. In other language what a predator eats is called prey. Pride: A family group of lions, defined by the continued presence of certain females. The males being more or less temporary adjuncts controlling access to the females until ousted by other males. Primary air pollutant: A pollutant that has not undergone chemical transformation; emitted by either a natural or an anthropogenic source. Primary consumers: First-order consumers (herbivores) feeding directly on living plants or plant parts. In other language the first consuming organism in a given food chain is called primary consumer. Primary producer’s: Organisms that produce food from simple inorganic material (that is photosynthetic plants and certain chemosynthetic bacteria). Primary production: Production of biological materials (biomass) by green plants or chemosynthetic autographs; the fixation of energy by autotrophs in an ecosystem. Primary productivity: Rate at which primary producers produce biomass Primary succession: Ecological succession or vegetation development starting on a newly exposed site (on a barren). The sequential development of communities where none previously existed. Primary treatment (of sewage): First step in sewage treatment to remove large solid objects by screens (filters) and sediment and organic matter in settling chambers. Principle of allocation: The Principle of allocation underscores the fact that if an organism uses energy for one function such as growth, it reduces the amounts of energy available for others functions such as reproduction. Organisms that produce many offspring are constrained, because of energy limitation to produce smaller offspring (seeds, eggs, or live young). Proactive government: One that is concerned with long range problems and lasting solutions. Contrast with reactive government. Proclimax: Community maintained by repeated disturbance. Producer (autotroph or producer organism): Autotrophic organisms such as green plants (almost always), certain chemosynthetic bacteria, photosynthetic algae that can manufacture food via photosynthesis; convert light or chemical energy into organism tissue and bind energy cycling through the ecosystem. Production: Amount of energy produced by an individual population or community per unit time. Productivity: The rate of conversion of sunlight by plants into chemical bond energy (covalent bonds in organic molecules). It is approximately the dry weight of plant material produced in an area per unit time. Profligate reproduction: Relies on large numbers of very small eggs, seeds etc. Profundal (zone): The zone in aquatic ecosystems or the deep-water area of a lake that lies beyond the depth of effective light penetration i.e. into which sunlight does not penetrate. Below the limnetic zone, where P/R<1. Promiscuous: Mating system in which males and females are not restricted to one sexual partner. Propagule: Unit of propagation, whether it is an egg, a seed or an asexually cloned individual of dispersal unit. Prospective law: One designed to address future problems and generate long-lasting solutions. Contrast with retrospective law. Protandrous reproduction: Relies on large young pr parental care. Protected area: A legally established land or water area under either public or private ownership that is regulated and managed to specific conservation objectives. Protocooperation: Association between two species in which both populations help from the association, but the association is not obligatory, frequently termed facultative cooperation. Proximate factors: Any characteristic of the environment that an organism used as a cue to behavioral or physiological responses; mechanisms following the process of an adaptation opposite of final factors. For example, day length (proximate factors are often not directly important to the organism’s well being). This factors is to reverse of ultimate factors. Pseudo-replication: Occurs when researchers try to increase sample size by increased sampling or calculates of the same experimental treatment unit, rather than replicating the number of treatment units; three ordinary type of pseudo-replication are- i) spatial, ii) temporal, and iii) sacrificial. Psilopsida: The psilopsida (Psilophytes) are the most primitive vascular plants. It is believed that this is the ancestor of the whole vascular plant group. Most members of this group are known only as fossils. There are two living genera such as Psilotum and Tmesipteris. These plants are still unchanged during this long period. They may well be regarded as living fossils. Psychrophilic: Organisms that live and thrive at temperatures below 20°C. Pterosaurs: Gliding reptiles that were contemporary with dinosaurs. Pulse stability property of systems adapted to particular intensity and frequency of perturbations populations that oscillate near the carrying capacity of a particular set of environmental conditions. Punctuated equilibrium: A theory of evolution stating that species fairly stable for long periods and that new species evolve rapidly over short periods of thousands of years that punctuate the equilibrium. This term is conflicting to gradualism. This theory does not agree with the Darwin’s theory of gradual evolution. Pupa: The resting stage of an insect in which the structure of a larva is broken down and an adult assembled. It is found in insects with complete metamorphosis such as beetles; butterflies and moths; bees, wasps and ants; and flies. Pycnolcine: Gradient of increasing density with depth in surface ocean waters. Pyramid of biomass: Model (or diagram) that represents the quantities of standing crop biomass at different trophic levels of an ecosystem. It is a graphical representation of the amount of biomass (organic matter) at each trophic level in an ecosystem. Pyramid of energy: Model (or diagram) that represent the of energy flow through the different trophic level of an ecosystem. Pyramid of number: Model (or diagram) that act for the number of organisms present at each trophic level of an ecosystem. It is frequently termed the Eltonian pyramid, attributed to Charles Elton a British ecologist. It is a graphical representation of the number of organisms of different species at each trophic level in an ecosystem. Pyrethrum: A plant chemical defense that is also used by humans as an insecticide. It is extracted from daisy like flowers and is relatively nontoxic to warm blooded animals. Q Quad: One quadrillion (1015) BTUs of heat. Quadrat: A basic sampling unit, typically 1 m2 used to sample grassland and old-field plant communities. Qualitative chemical: Defenses chemically inexpensive poisons and toxins in plants that constitute effective barriers to herbivory Qualitative defense: Allelopathy employing specific toxins (e.g., alkaloids). Quantitative chemical defenses: Chemically expensive compounds in plants, such as tannins, that constitute barriers to herbivory by reducing plant quality or palatability. Quantitative defense: Allelopathy employing specific toxins (e.g., tannins). Quaternary: Geological period from 2 million years ago to the present, includes the Pleistocene and recent epochs. Queen: In Hymenoptera and termites, the individual that lays eggs only. where the other individuals are sterile and make the nest and carry out other tasks, also assist the queen. Quinine: An alkaloid extracted from cinchona bark; it is an effective treatment for malaria. R R- horizon: Parent rock below the C horizon of soil Race: The term species and geographical race are frequently used interchangeably by taxonomies. Variety:Any deviation from the species is called variety. e.g. leather carp is a variety of common carp. Alien species: Species occurring in an area its natural distribution is called alien species, e.g. exotic species. RAD (Radiation Absorbed Dose): The amount of radiation absorbed by an object or organism, expressed as the amount of energy (in ergs) per gram of absorbing tissue or material. Unit of radiation defined as an absorbed dose of 100 ergs of energy per gram of tissue. One rad = 100 ergs of energy deposited in one gram of tissue. Radiation ecology: The branch of ecology concerned with the effects of radioactive materials on living systems and with the pathways by which these materials are dispersed within ecosystems. Radiation: The transfer of heat through electromagnetic radiation (mainly infrared light). This transfer of heat H1, is often called simply radiation. All objects above absolute 0, above –2730C, give off electromagnetic radiation, but the most obvious source in our environment is the sun. Radioactive waste: Any solid or liquid waste material-containing radioactivity. It is produced by research labs, hospitals, nuclear weapons factories, and fission reactors. Radioactive: The property of some chemical elements to spontaneously emit radiation from unstable atomic nuclei. Radioactivity: Radiation released from unstable nuclei. Alpha and beta particles released such rays. Radionuclide: Isotope of elements that emit ionizing radiations; radioactive forms (isotopes) of elements. Rain forest: Tropical forests (woodland) with regular heavy rain (at least 100 inch), constantly high temperatures, prolific plant growth and marked by tall broad-leaved evergreen trees forming a continuous canopy Rain shadow: Arid downwind side of mountain range; dry region on the lee side of mountains. Raised bog: In which the accumulation of peat has raised its surface above both the adjacent land and the water table; it develops its own balanced water table. Ramet: Any individual belonging to a clone; for example, bamboos shoot from an underground runner. Random distributing: Distribution of individuals in a random pattern independent of all other individuals. It is a kind of distribution in which individuals within a population have an equal chance of living anywhere within an area. Random mating: Mating system whereby diploid adults mate at random independently with their opposite sex. Random union of gametes: Mating system whereby gametes unite at random independently of their genotype at specific loci. Random variation: Estimate or measurement dispersion around the most likely random variable. Randomization: Chance-mediated assignment of items or units to treatments to reduce researcher bias. Range of tolerance: Range of physical and chemical factors in which an organism can survive. When the upper or lower limits of this range are exceeded, growth, reproduction, and survival are threatened. Rangeland: Grazing land for cattle, sheep, and other domestic livestock. Rank-abundance curve: A curve that portrays the number of species in a community and their relative abundance; constructed by plotting the relative abundance of species against their rank in abundance. Rate of primary production: The amount of energy fixed by autotrophs in an ecosystem over some interval of time. R-C-S continuum: Postulated replacement series of plants of ruderals, competitive and stresstolerant strategies. Reactive distance: Effective targeting range of a predator. Reactor core: Assemblage of fuel rods and control rods inside addressing present day problems as they arise. Shows little or no concern for long term by water to help control the rate of fission and absorb the heat. Realized niche: Portion of fundamental niche occupied by a population; this niche determined in the presence of competitions and other biotic interactions, such as predation. In operation it is the actual niche of a species whose distribution is restricted by biotic interactions such as competition, predation, disease, and parasitism. Realm (biogeographic): Latitudinal expanse in which organisms have comparable adaptations. Recalcitrant seed: Seed that does not survive drying and freezing Recombination: Exchange of genetic material (mixing of genes) from paternal and maternal chromosomes; resulting from independent assortment of chromosomes and their genes during gamete production (during meiosis); followed by a random mix of different sets of genes at fertilization. Recruitment: Addition of new individuals to a population by reproduction. Recurrent mutation: A mutation from an allele to another allele that is already in the gene pool; repeated mutation. Recycling: A strategy to reduce resource use by returning used or waste materials from the consumption phase to production phase of the economy. Red data book: It is the name given to the book listed with threatened plants or animals of any region. On the global level, the IUCN published Red Data Book in two volumes. Red queen: Hypothesis that evolution results as selection tracks persistent environmental change. Reduction factors: Abiotic and biotic factors that tend to disease population growth and help balance populations and ecosystems, offsetting growth factors. Reductionism: Theory that complex systems can be explained by analyzing the simple, basic parts of those systems. Refuge site: Where individuals of an exploited population find protection from predations and parasites. It is an isolated area where plants and animals find refuge from unfavorable environmental conditions. It is also means location where flora and fauna that were once widespread, but now considerably diminished in area, remain present. Regenerated corridor: Regrowth of a strip of natural vegetation (such as a hedgerow) that develops along fences due to the natural processes of secondary succession. Region (biogeographic): Continental expanse, the organisms of which are taxonomically related. Regolith: Mantle of unconsolidated material below the soil from which soil develops. Regular distribution: A distribution of individuals in a population in which individuals are uniformly spaced or dispersion. Rehabilitation: The recovery of specific ecosystem services in a degraded ecosystem or habitat. Relative abundance: Proportional representation of a species in a sample or a community. It is a value typically used to describe the dominance of tree spices in a forest community. Relative fitness: A fitness coefficient scaled so that the largest equals to 1. Relative humidity: Percentage of moisture (water vapor) present compared with saturation under existing temperature and pressure conditions. A measure of the water content of air relative to its content at saturation; relative humidity = water vapor density/saturation water vapor density x 100. It is expressed as a percentage. Relative wind: Airflow, like airplanes and birds generate lift by having their wings intercept the airflow at an angle. Relative wind is also known as the angle of attack. Relaxation: In Island biogeography it means loss of species following decreased access or reduction in area. Relict: Surviving species of a once widely dispersed group. Rem (roentgen equivalent man): A measure that accounts for the damage done by a given type of radiation. One rad = one rem for X rays, gamma rays, and beta particles, but one rad = 10 to 20 rems for alpha particles, because they do more damage. Remnant corridor: A strip of native vegetation left uncut after the surrounding vegetation is removed. Remote sensing: Gathering information about an object without direct contact with it, mainly by gathering and processing electromagnetic radiation emitted or reflected by the object; such measurements are typically made from remote sensing satellites. Render pest: A serious viral disease of ruminants that decimated herds of cattle and native ruminants in Africa. Renewable resource: A resource replaced by natural ecological cycles (water, plants, animals) or natural chemical or physical processes (sunlight, wind). It is a resource that is replenished. Replacement series diagram: A diagram showing the outcome of competition between two species in experiments in which the initial ratio of the two species was varied. Replacement-level fertility: Number of children of a couple must have to replace themselves in the population. Reproductive age: Age during which most won offspring (ages 14-44). Reproductive effort: The allocation of energy, time, and other resources to the production and care of offspring, generally involving reduced allocation to other needs such as maintenance and growth. Reproductive isolation: Any of many mechanisms that prevent species from interbreeding or producing viable offspring. Reproductive value potential: Reproductive output of an individual at a particular age (x) relative to that of a newborn individual at the same time. Rescue effect: The concept that extinction is prevented by an influx of immigrants. Reserve: Deposit of energy or minerals that is economically and geologically feasible to remove with current and foreseeable technology. Residence time: Length of time of a chemical spends in the environment. Residual reproductive value: Reproductive value of an individual reduced by its expected present reproduction. Residual soil: A soil developed at the source of its parent materials. Resilience stability ability: Ability of a system to recover from a perturbation when it is disturbed. Resilience: Capacity of an ecosystem to absorb changes and quickly return to its original state after disturbance. Resistance of community: The capacity of a community or ecosystem to maintain structure and/or function in the face of potential disturbance. Resistance: Ability of a system to resist changes and to maintain its structure and function from a disturbance. Resource (as a measurement of a mineral or fuel): Total amount of a mineral or fuel on earth. Generally, only a small fraction can be recovered. Resource (in general): Anything used by organisms needs to meet their needs, including air, water, minerals, plants, fuels and animals. Resource allocation: Action of distribute and the supply of a resource to a specific use. Resource corridor: A strip or narrow piece of natural vegetation that extends across the landscape (such as a galley forest along a stream). Resource limitation: Limitation of population growth by resource availability. Resource partitioning: The use of different types of limiting resources by two or more species or category of organisms. Resource: Environmental component, utilized by a living organism during its growth, maintenance, or reproduction. Resource-use Competition: Competition between two species in which each population harmfully affects the other indirectly in the struggle for resources in short supply. Respiration: Metabolic assimilation of oxygen accompanied by production of carbon dioxide and water, release of energy, and breaking down of organic compounds. Resprout species: Fire-dependent species of plant that keep more energy into underground storage organs and less into reproductive structure. Resting schools: Schools of fishes that relax on coral reefs during the day and feed in a different place at night. Restoration ecology: Study of the use of ecological theory to the ecological restoration of highly disturbed sites of a plant and animal community or ecosystem to states the existed previous to the disturbance. It is the branch of ecology that focusing on the application of ecological theory to restoration theory to return of highly disturbed sites e.g. ecosystems, and landscapes. Restoration: The return of an ecosystem or habitat to its original community structure, natural complement of species and function. Restriction enzymes: The enzymes produced by bacteria to cut up foreign DNA, used in DNA studies to cut DNA molecules at particular places called restriction sites. Restriction fragments: The DNA fragments resulting from the cutting of a DNA molecule by a restriction enzyme. Restriction sites: The particular locations where a restriction enzyme cuts a DNA molecule. Rete: A large network of small blood vessels carrying arterial and venous blood, which acts as a heat exchanger in mammals and certain fish and sharks. Retorting: Process of removing kerogen from oil shale, usually by burning or heating the shale. It can be carried out in surface vessels (surface retorting) or underground in fractured shale (in situ retorting). Retrospective law: One that attempts to solve a problem without giving much attention to potential future problems. Prospective law is a opposite term of retrospective law. Reverse osmosis: Means of purifying water for pollution control and derivative. Water is forced through porous membranes; pores allow passage of water molecules but not impurities. Reward feedback: Positive feedback (increased growth or survivorship) by an organism or trophic level that maintains the survival of its food resource. Reynold’s number: Relationship between length, speed and viscosity that define motion through fluids to explain the comparative amount of the pressure and resistance components in drag. It is used for objects in any fluid including water and air. Rheotrophic: Applies to wetlands (such as fens), especially bogs that obtain much of their nutrient input from groundwater. Rhizobia: A bacteria genus capable of living mutualistically with leguminous plants. Rhizome: Horizontally growing underground stem that through branching gives rise to vegetative structures. Rhizoplane: Root surface. Rhizosphere: Regions of soil activity immediately surrounding roots Richness: Total species number i.e. the number of species present in an area. It is a component of species diversity. Riparian vegetation: A vegetation growth along banks of rivers or streams. Riparian zone: The transition between the aquatic environment of a river or stream and the upland terrestrial environment, generally subject to periodic flooding and elevated groundwater table. Risk acceptability: A measure of how acceptable a hazard is to a population. Risk assessment: The science of determining what hazards a society is exposed to from natural and human causes and also the probability and severity of those risks. Risk probability: The likelihood a hazardous event will occur. Risk severity: A measure of the total damage a hazardous event would cause. River continuum concept: A model that predicts change in physical structure, dominant organisms, and ecosystem processes along the length of a river system of a temperate river. The organisms of river systems change from headwaters to mouth. These patterns of biological variation along the courses of river have given rise to a variety of theories that predict downstream change in rivers and their inhabitants. One of these theories is the river continuum concept. Root nodules: Minute bulbous structures on the roots of legumes that port nitrogen fixing bacteria. Rosenzweigh rule: It states that the logarithm of net primary productivity is linearly related to the logarithm of evapotranspiration. R-selection: selection under low population densities. It favours high reproductive rates under conditions of low competition. It tends to dominate in early stages of ecological succession. It is a form of natural selection favoring higher population growth rate. R selection is predicted to be strongest in disturbed habitats. Ruderals: Plant with colonizer strategy that live in highly disturbed habitats and that may depend on disturbance to persist in the face of potential competition from other species. There are several characteristics of ruderals that allow them to persist in habitats experiencing frequent and intense disturbance, which he defined as any mechanisms or processes that limit plants by destroying plant biomass. One of the characteristics of ruderals is their capacity to grow rapidly and produce seeds during relatively short periods between successive disturbances. Rule of constant yield: Observation that the yield from a plot is independent of the sowing densities. The rule applies to a range of intermediate sowing densities. Ruminant: An ungulates with a three or four-chambered stomach; the large first chamber is known as the rumen, in which bacterial fermentation of plant matter (cellulose) is broken down with the aid of mutualistic microorganisms and consumed. Ruminants repeatedly regurgitate and chew the contents to the rumen to speed the digestive process. Ruminants include cattle, antelopes, sheep, and deer etc. Runoff: The amount of water falling as precipitation that eventually finds its way to streams and rivers. S Saber-toothed blennies: A group of marine fishes of the family Blenniidae that includes cleaner mimics and slash-and-dash predators. Salinity: The salt content of water. Salinization: Deposition of salts in irrigated soils making soil unfit for most crops. This is caused by rising water table due to inadequate drainage of irrigated soils. Salt marsh: A marine shore ecosystem dominated by herbaceous vegetation, found mainly along sandy shores from temperate to high latitudes. Saltwater intrusion: Movement of salt water from oceans into freshwater aquifers, caused by depletion of the freshwater aquifers or low precipitation or both. Sample: Separation of all observation or individual in a population or sampling universe. Sanitary landfill: Solid waste disposal site where garbage is dumped and covered daily with a layer of dirt to reduce odors, insects and rats. Saprobe: Synonym for decomposer-hence “saprobe chain”. Saprophage: Organism that feeds on dead plant and animal matter. Saprotroph: Organism that feeds on dead organic matter, organism that absorbs organic nutrients from dead plant or animal matter. Saturation dispersal: Movement of individuals out of a population that has reached or exceeded carrying capacity. Saturation water vapor pressure: The pressure exerted by the water vapor in air that is saturated with water vapor. Savanna: Tropical grassland on which usually with scattered trees or shrubs. Scatter hoarded: A term applied to seeds gathered by mammals and stored in scattered hoards. Schistosomiasis: A serious human disease caused by parasitic nematode worms that live inside the blood vessels. The disease is contracted by contact with water containing the immature forms of the worms, which have aquatic snails as intermediate hosts. The African variety ‘schistosomiasis’ is called ‘bilharzia’. Sclerophyll: Refers to woody plant with hard, leathery, evergreen leaves that prevents moisture loss. Scope: Inference target population. Scraper: Aquatic insects that feed by scraping algae from a substrate. Scrubber: Pollution control device that removes particulates and sulfur oxides from smokestacks by passing exhaust gases through fine spray of water containing lime. Search image: Mental image formed in predators, enabling them to find more quickly and to concentrate on a common type of prey. People searching for a cryptic animal often quickly find additional individuals after the first is spotted, presumably because they form search images also. Second generation pesticides: Synthetic organic chemicals such as DDT that replaced older pesticides such as sulfur, ground tobacco, and ashes. Generally resistant to bacterial breakdown. Second law efficiency: Measure of the efficiency of energy use, taking into account the unavoidable loss (described by the second law of thermodynamics) of energy during energy conversion. This is calculated by dividing the minimum amount of energy required to perform a task by the actual amount used. Second Law of Thermodynamics: The essential feature of the second law of Thermodynamics is that every system left to itself change rapidly or slowly in such a way to approach a definite final state is called the state of equilibrium. The second law of thermodynamics is also known as the law of increasing entropy (means disorder or disorganization). When energy is transformed from one form to another, it is degraded; that is, it is converted from a concentrated to a less concentrated form. The amount of useful energy decreases during such conversion (in other words, no transformation of energy into potential energy is 100 percent efficient). Secondary compounds: Chemical compounds not used for metabolism but chiefly for defensive purposes; compounds that interfere with specific metabolic pathways, physiological processes, taste response, or reproductive success of herbivores Secondary consumer: Second consuming organism in food chain. Belongs to the third trophic level. Secondary plant metabolites: Toxic compounds manufactured by plants, frequently tending to be autotoxic. Secondary pollutant: A chemical pollutant from a natural or anthropogenic source that undergoes chemical change as a result of reacting with another pollutant such as sun light, atmospheric moisture, or some other environmental agent. Secondary production: The production by consumer organisms Secondary productivity: Rate of storage of organic matter by heterotrophs; rate at which heterotrophs (primary or secondary consumers) accumulate biomass by the production of new somatic or reproductive tissues Secondary substances: Organic compounds produced by the plants that are utilized in chemical defense. Secondary succession: Plant succession taking place on sites that have already supported life that is succession following the disturbance of a preexisting successional stage or climax (such as an abandoned crop field); for instance, forest succession following a forest fire or logging. Secondary succession: The sequential development of biotic communities occurring after the complete or partial destruction of an existing community by natural or anthropogenic forces. Secondary treatment (of sewage): After primary treatment, removal of biodegradable organic matter from sewage using bacteria and other microconsumers in activated sludge or trickle filters. Also removes some of the phosphorus (3096) and nitrate (50%). See also tertiary treatment. Secured landfill: One lined by clay and synthetic liners in an effort to prevent leakage. Sediment: Soil particles, sand, and other mineral matter eroded from land and carried in surface waters. Sedimentary cycle: Any global cycle where geological processes, such as the weathering of existing rock, erosion, and sedimentation, dominate or originate the cycle; calcium and potassium exemplify this type of cycle Seed bank: A facility designed for the ex-situ conservation of individual plan varieties through seed preservation and storage. Seed bank: Accumulation in soil of seeds with delayed germination. Seedling bank: Accumulation of seedlings maintaining themselves in dim light on a forest floor. Seiche: Oscillation of a structure of water about a point node. Selection coefficient (s): The relative selection costs or (decreased or increased fitness) associated with a particular biological trait. Selectionists: Geneticists who believe that most naturally occurring variation in enzymes causes changes that affect the functioning of those enzymes sufficiently to be 'detectable’ by selection. Selective advantage: An advantage one member of a species has over others by virtue of some adaptation it has acquired. Selective cutting: Restricted removal of trees. Especially useful for mixed hardwood stands. One may compare this term with clear-cutting and shelter wood cutting to understand clearly. Selective death: A death attributed to the deleterious expression of a genotype. It is a death that would have avoided had the individual and had the optimum genotype. Self-incompatibility: Incapacity of a plant to fertilize itself; such plants must receive pollen from another plant in order to develop seeds. Selfing: Producing zygotes by self-fertilization. Self-regulation: Process of population regulation in which population increase is prevented by deterioration in the quality of individuals that make up the population. In other language it is the population regulation by internal adjustments in behaviour and physiology within the population, rather than by external forces such as predators. Self-thinning curve: In populations of plants limited by space or the resources. This is the characteristic logarithmic relationship between number and biomass. Self-thinning rule: A rule resulting from the observation that plotting the average weight of individual plants in a stand against density often produces a line with an average slope of approximately -3/2. Selfthinning rule also called -3/2 rule. Self-thinning: Reduction in population density as a stand of plant increases in biomass, due to intraspecific competition. Semi-species:Geographically non-isolated individual that bears occasionally intermediate status between subspecies and species. Semelparity: Having only one terminal reproductive effort in a lifetime. It involves production of all of an organism's offspring in one event, generally over a short period of time. Semiarid: Area of quite dry weather with rainfall between 25 and 60 cm in a year; with an evapotranspiration rate sufficient so that potential loss of water to the environment exceeds inputs. Senescence: Process of aging. Seral stage: One of the successional stages in a sere. Seral: Series of stages that follow one another in succession. Sere: An entire successional sequence, leading from bare to a mature. The word also means ‘climax community’ or ‘terminal community’. Serpentine soil: Soils derived from ultra basic rocks that are high in iron, magnesium, nickel, chromium, and cobalt; and low in calcium, potassium, sodium, and aluminum. It supports distinctive communities. Sesquioxides: Generic term for a mixture of iron and aluminum oxides. Sessile: Animal that is attached to an object or is fixed in place, e. g, barnacles. Sewage treatment plant: Facility where human solid and liquid wastes from homes, hospitals, and industries are treated, primarily to remove organic matter, nitrates, and phosphates. Sex ratio: Proportion of males to females. Sexual reproduction: Reproduction that involves the fusion of gametes. Sexual selection: Darwin takes sexual selection as an effective part of natural selection. In Darwin words, “There is a second agency at work in most unisexual animals, tending to produce same effect namely the struggle of the males for the females. These struggles are generally decided by the law of battle (Darwin, 1958). Nelson (2003) acknowledged that biologists declared that sexual-selection theory should be rethought and perhaps discarded altogether. Sexual behavior often doesn’t match gender and that many species exhibit flexible sexual expression. She (Nelson, 2003) also reported that according to Roughgarden many animals and plants function as both sexes at the same time, and some, like the hamlet fish, can change sex as conditions change, in a matter of minutes. So, sexual selection is not applicable in this case (Internet). Sexual selection: Results from differences in reproductive rates among individuals as a result of differences in mating success, due to intrasexual selection, intersexual selection, or a mixture of the two forms of sexual selection. Shade tolerant: Plants those are able to grow and reproduce under low light conditions. Shale oil: Thick, heavy oil formed when shale is heated. This oil can be refined to produce fuel oil, kerosene, diesel fuel and other petroleum products and petrochemicals. Shannon-weaver: Index measure of the apportionment of species in a community based on information theory, published in 1949 by Claude E Shannon and Warren weaver. Shelford law of tolerance: Law, proposed by V.E. Shelford in 1911, stating that the presence and success of an organism or species depends on either the maximum and minimum resource or set of conditions. Shelter belts: Rows of tress and shrubs planted alongside fields to reduce wind erosion and retain snow to increased soil moisture. Shelter belts may also be used to reduce heat loss from wind and thus conserve energy around homes and farms. Shelter wood cutting: Three step process spread out over years (1) removal of poor-quality trees to improve growth of commercially valuable trees and allow new seedlings to become established, (2) removal of commercially valuable trees once seedlings are established, and (3) cutting remaining mature trees grown from seedlings. Short-day organisms: Plants and animals that come into reproductive condition under conditions of short days (days with less than a certain maximum length). Shredders stream: Invertebrates, typically aquatic insects that feed on coarse particulate organic matter. Sib selection: A pattern of artificial selection in which the breeding reserve for each generation consists of the brothers and sisters of the individuals. Sibling species: Species with similar appearance but unable to interbreed Sickle cell anemia: A fatal disease caused by distortion of the red blood cells. It occurs in individuals, usually of African origin, who are homozygous for a gene that changes one amino acid residue in the protein hemoglobin. Heterozygote, however, are resistant to a dangerous kind of malaria found in Africa. Sigmoidal curve: An S-shaped curve. Sigmoidal Population growth curve: An S-shaped pattern of logistic growth of population growth, with population size leveling off at the carrying capacity of the particular habitat or the environment. Signal receiver: Term for dupe in a mimicry system. Silurian period: A period of the mid Paleozoic era about 430-395 million years ago. Simplified ecosystem: One with lowered species diversity usually as a result of human intervention. Sink hole: Hole created by sudden collapse of the earth’s surface due to groundwater overdraft, a form of subsidence. Sink: Habitat where local mortality exceeds local reproductive success. Site: Combination of biotic, climatic and soil conditions which determine an area’s capacity to produce vegetation. Size escape: Attaining a size large enough so that predators cannot be effective. Size-selective predation: Prey selection by predators based on prey size. Slash-and-burn agriculture: Farming practice in which small plots are cleared of vegetation by cutting and burning. Crops are grown until the soil is depleted; then the land is abandoned. This allows the natural vegetation and soil to recover. This type of agriculture was common practice of early agricultural societies living in the tropics. Sludge: Solid organic material produced during sewage treatment. Small-scale phenomena: A phenomena that take place on a local scale. Smelter: A factory where ores are melted to separate impurities from the valuable minerals. Smog: Originally refer to pollute air and water vapour (combination of smoke and fog) found in industrial cities. Also pertains to pollution called photochemical smog, found in newer cities. Snag: Dead or partially dead tree at least 10.2 cm dbh and 1.8 m tall, important for cavity-nesting birds and mammals. Social adaptation: Any adaptation that facilitates behavioral interactions among individuals of the same species; usually does not include reproductive activities. Social behavior: A behavior involving unrelated or distantly related individuals for the same population. It usually does not include courtship, mating, parent-offspring, and sibling interactions and it reject interactions between close relatives such as parents and offspring. Social Darwinism: The application (or misapplication) of the theory of evolution to social behavior. Social facilitation: Enhancement of any behavior by association with other individuals engaged in similar behavior. Social feedback: Direct interaction by which some individuals exercise control over the activities of other individuals so as to regulate population processes. Social group: A group of individuals of the same species formed by mutual attraction of individuals to each other and within which individuals are interdependent to some degree for their well being. Social insects: Wasps, bees, ant, and termites, which often live in complex societies with individuals performing specialized tasks, such as defending, the nest building, or care for the young. Social mimicry: Evolution of similar appearance or behavior in unrelated species to facilitate direct interaction between individuals. Also called character convergence. Social parasite: Animal that uses other individuals or species to rear it’s young, for example cowbirds. Social pathology: A syndrome of physiological and behavioral disturbances, caused by crowding, that lead to reduced fecundity and increased mortality. Sociality: Group living generally involving some degree of cooperation between individuals. Sociation: Plant community unit defined by measured minimum area. Society: A group of organisms of the same species characterized by specialization of individual roles, divisions of labor, and mutual dependence. Sociobiology: Sociobiology is the study of the evolution of animal’s social behaviours by natural selection. It is a new discipline that applies biological principles to explain the behaviors of all social animals including man. Wilson (1975) mentioned in his book “Sociobiology: The New Synthesis” that sociobiology is the systematic study of the biological basis of all social behaviours. He further pointed out that it is a branch of evolutionary biology and practically of modern population biology. In addition, the extension of NeoDarwinian principles to social behaviours, produce the discipline of sociobiology. Sociocusis: Hearing loss from human activities. Its opposite word is presbycusis so, one may be contrast this word (sociocusis) with presbycusis to understand clearly. Soil association: Group of defined and named soil taxonomic units occurring together in an individual and characteristic pattern over a geographic region. Soil characteristics: Soil characteristics such as texture, nutrient status, and depth those are well documented as important factors determining the competitive relationships and growth rates of plants in a wide variety of environments. Soil conservation: An ethic practice by farmers and stakeholders to preserved the loss of soil or decrease in soil quality. Soil erosion: Removal of soil particles by water and wind, frequently accelerated by human disturbance. Soil horizon: Developmental layer in the soil with its own characteristics of thicknes, color, texture, structure, acidity, nutrient concentration and the like. Soil horizons: Layers found in most soils. Soil profile: Distinct strata or layering of horizons in the soil. Soil series: Basic unit of soil classification which are essentially alike in all major profile characteristics except texture of the A- horizon. Soil series are usually named for the locality, where the typical soil was first recorded. Soil structure: Arrangement of soil particles and aggregates. Soil texture: Relative proportions of the three particle sizes (sand, silt, and clay) in the soil. Soil type: Lowest unit in the natural system of soil classification, consisting of soils which are alike in all characteristics including texture of the A-horizon. Solar collector: Device to absorb sunlight and convert it into heat. Solar constant: Flux of solar energy, reaching the upper atmosphere (about 2 langleys). It is a rate at which sunlight reaches the atmosphere of Earth, that is equal to 1.94 g cal cm-2.min-1. Solar energy: Energy derived from the sun (heat) and natural phenomena driven by the sun (wind, biomass, running water). Solar powered: Refers to systems run and preserved by solar energy. Solar system: Group of planets revolving around a star. Solar tracking: Trait of certain plants in which plants orients their leaves to the face of the sun during the entire day. Solifluction: The slow movement of tundra soils down slopes as a result of annual freezing and thawing of surface soil and the actions of water and gravity. Son path: A term coined by Amory Lovins to describe such practices as conservation, efficient use of energy, and renewable energy systems such as solar and wind. It is characterized by high labor intensity, decentralized energy production and small scale technology. Its opposite phrase is hard path so, one may be contrast this phrase (son path) with hard path to understand clearly. Sonic boom: A high-energy awakens creating an explosive boom that trails after jets traveling faster than the sound. Source population: A habitat where the reproductive success of a population provides individuals for sink habitats. Southern oscillation: An oscillation in atmospheric pressure that extends across the Pacific Ocean. Spaceship earth: Image introduced in the 1960s to promote a better appreciation of the finite nature of earth’s resources and the ecological cycles that replenish oxygen and other important nutrients. Spate: Sudden flooding in a stream. Spatial niche: Functional status of a species in its habitat expressed as a spatial dimension. Specialist: Organism that has a narrow niche, usually feeding on one or a few food materials and adapted to a particular habitat. Specialization: Restriction of an organism or a population activity to a portion of the environment. It is a trait that enables an organism (or one of its organs) to modify in order to adapt to a particular function or environment. Speciation: The splitting or separation process of a species into two or more reproductively isolated populations that creates new kinds of organisms i.e. formation of new species. Species apportionment: Apportionment of one species in a defined area compared to the apportionment (number, biomass) of other species in the same area. Species diversity: Species diversity: A measurement of diversity in a habitat or in a biological community. It counts of the number of different species. Species diversity increases with the species evenness and the species richness. Species evenness: The relative abundance of species in a community or collection. Species packing: Enhance in species diversity within a relatively narrow range of resource variation. Species richness: Number of different species in given area or in a community. Species selection: Form of group selection in which sets of species with different characteristics; some species become extinct or do not continue to diversity; whereas others continue to split into new species. Species turnover: Changes in species composition on islands resulting from some species becoming extinct and others immigrating. Species: A group of plants, animals, or microorganisms that have a high degree of similarly, generally can interbreed only among themselves; and which are reproductively isolated from other such groups. A distinct kind of organism; when populations of two kinds occur together without interbreeding they are considered different species.It has several class such as- i) Sub- Species: A geographically defined aggregate of local populations which differs taxonomically from other such subdivisions of the species, e.g. Mirror carp, Scale carp etc ii) Sibling species- Morphologically similar or identical population that is reproductively isolated iii) Sympatric species- Geographically non-isolated that live in same area but they carry their own characteristics iv) Allopatric species- Species formed during geographical isolation are called allopatric species. v) Monotypic species-Species that are not sub divided into subspecies are called monotypic species. vi) Polytypic species- Species that contain two or more sub species are called polytypic species. vi) Semi-species- Geographically non-isolated individual that bears occasionally intermediate status between subspecies and species. vii) Race- The term species and geographical race are frequently used interchangeably by taxonomies. viii) VarietyAny deviation from the species is called variety. e.g. leather carp is a variety of common carp. ix) Alien species: Species occurring in an area its natural distribution is called alien species, e.g. exotic species. x) Indicator species: A species whose status provides information on the overall condition of the ecosystem and of other species in that ecosystem. xii) Introduced / Exotic species/Aline species: Exotic organisms that have arrived from other parts of the world (often because humans have transported them) are known as introduced or alien species. The impact on local ecosystems are – (a) they may prey on native species or (b) they may compete for resources with native species. (c) interbreed with native organisms and this unnatural hybrids may differ greatly from well-adapted native plants and animals. Xii) Invasive alien species: A species which does not occur naturally in a place, and spreads rapidly over large areas e.g. spreading of African magur in Bangladesh. Xii) Extinct (EX) species /Extinction: No reasonable doubt that the last individual of the species has died. It is the evolutionary termination of a species caused by the failure to reproduce and the death of all remaining men the species; he natural failure top adapt to environmental change. Specific heat: Amount of energy that must be added or removed to raise or lower temperature of a substance by a specific amount. It is the number of calories required to raise 1g of a substance at 10c. Sperm precedence: Event in which sperm from later mating tend to displace those from earlier mating. Spiraling length: The length of stream required for an atom of a nutrient to complete a cycle from release into the water column to reentry into the benthic ecosystem. Spiraling: Mechanism of preservation of nutrients in flowing water ecosystems, connecting the mutually dependent processes, nutrient recycling and down stream movement. Spontaneous abortion: Loss of an embryo or fetus from the uterus not caused by surgery. Generally it is the result of the chromosomal abnormalities. Its conflicting term is induced abortion. Spontaneous generation theory of life: For over two thousand years spontaneous generation theory of life was accepted. This theory opine that the formation of living things from nonliving matter, was believed as a fact of nature such as flies and maggots from rotting meat and barnyard manure, lice from sweat, glow worms from rotting logs, eels and fish from sear mud, and frogs and mice from the moist earth. Francesco Reddi, an Italian physician, demonstrated in 1668 that maggots in meat are the larvae of flies and that if the meat is protected so that adult flies cannot lay their eggs on it, no maggots appear there. The Italian biologist Lazzaro Spallanzani (1729-1799) showed that if broth (thin soup) is placed in sealed containers and adequately sterilized, they remain devoid of life. In 1862 the great French scientist Louis Pasteur convinced most people that spontaneous production does not occur. Spring overturn: Annual cycle in deep lakes in temperate climates in which surface and subsurface waters mix. SST (supersonic transport): Jet that travels faster than the speed of sound. Stability: Capability of a system of resist to change or to recover fast after a disturbance; absence of fluctuations in a population. It is the persistence of a community or ecosystem in the face of disturbance, usually as a consequence of a combination of resistance and resilience. Stable age distribution: Constant proportion of individuals of various age classes in a population through population changes. The age distribution ultimately is attained by a population in a constant environment. Stable isotope analysis: An analysis of the relative concentrations of stable isotopes such as 13C and 12C, in materials; used in ecology to study the flow of energy and materials through ecosystems. Stable runoff: Amount of surface runoff that can be counted on from year to year. Stablizing selection: It is a selection in which individuals near the average for a trait reproduces more than those far from the average. Stand: Unit of vegetation that is essentially homogeneous in all layers and differs from adjacent types qualitatively and quantitatively. Standard deviation: Statistical measure defining a normal dispersion of values about the mean in a normal distribution. Standing crop: Amount of biomass weight of living biological materials in a particular area (per unit area) at a given time or at a specific time. Star: Spherical cloud of hot gas, such as the sun, fueled by nuclear fusion reactions in its core. Stasis: A condition in which species remain essentially unchanged for stretches of geological-time often millions of years. State variables: Sets of numbers used to represent the state or condition of a system at a particular time. Static life table: A life table constructed by recording the age at death of a large number of individuals; the table is called static, because the method involves a photograph of survival within a population during a short interval of time. Static life table is a second way to estimate the patterns of survival in wild populations to record the age at death of a large number of individuals. This method differs from the cohort approach because the individuals in a sample are born at different times. Stationary age distribution: Special form of stable age distribution in which the population has reached at a constant size, the birth rate equals the death rate, and age distribution remains fixed. Statistical inference: Conclusion based on a mathematical summary of the data. Statutory law: Law enacted by Congress or a state legislature. Its opposite speech is common law. So, one may be contrast this speech (Statutory law) with common law to understand clearly. Steady state economy: Economic system characterized by relatively constant GNP, dedication to essential goods and services, and maximum reliance on recycling, conservation and use of renewable, resources. Also spaceship or sustainable, economy. Steady state temperature: A constant temperature that results when the input of heat in an animal balances its output rate of heat. Steady state: A condition where an input rate balances an output rate. It is also called equilibrium of fixed point. Steno: Narrowly restricted, as in stenothermal or stenohaline for organisms with narrow tolerances to temperature or salt. Stenoplastic: Having little or no modification plasticity; steno means narrow; opposite of ceroplastic. Steno-prefix: Meaning ‘narrow’ derived from Greek stenos. Sterilization: A highly successful procedure in males and females to prevent pregnancy. In males the ducts (vas deferens) that, carry sperm from the testicles are cut and tied (vasectomy); in females the Fallopian tubes, or oviducts, which transport ova from the ovary to the uterus, are cut and tied. Stochastic model: A mathematical model is based on probabilities and predictions of the model are not fixed but variable. This model is opposite of deterministic model. Stochastic: Referring to patterns resulting from random factors or effects. Stomata: A tiny opening in the underside and sometimes the top of leaves and stems through which gases enter and leave a plant. Strain the extending of a material, such as a tendon; the change in length caused by the force. Stratification: Separation of an aquatic or terrestrial community into distinguishable layers on the basis of temperature, moisture, light, vegetative structure, and other such factors making zones for various plant and animal types. Stratosphere: A layer of earth's atmosphere that extends from about 16 km to an altitude of about 50 km. Stream order: Numerical classification of stream drainage based on stream structure and function from the headwaters to the mouth of the stream. Stream spiraling: Transfer and cycling of necessary element (such as carbon, nitrogen, and phosphorus) between organism and available pools as they move downstream. Streambed aggradation: Deposition of sediment in streams or rivers thereby reducing their water-carrying capacity. Streambed channelization: An ecologically unsound way of reducing flooding by deepening and straightening of streams, accompanied by removal of trees and other vegetation along the banks. Stress: A condition that forces a deviation from homeostasis; a stress consists of any strong negative environmental conditions that induce physiological responses in an organism or alter the structure of functioning of an ecosystem. It is the force on a thing, tending to create deformation as in the force on a tendon. Stressor: A stimulus or factor producing stress. Stress-tolerant plant: A plant that live under conditions of high stress but low disturbance. Some species are tolerant to the environmental extremes that occur. These are the species that the referred to as “stress-tolerant”. Strip cropping: Soil conservation technique in which alternating crop varieties are planted in huge strips across fields to reduce wind and water erosion of soil. Stromatolite: Carbonate structured made by marine algae. Strong interactions: Feeding activities of a few species that have a dominant influence on community structure. Structured deme: System of isolated populations without general and continuous mixing of genes throughout the population. Subclimax: A stage of succession along a sere prevented from progressing to the climatic climax by fire, soil deficiencies, grazing and similar factors. Subduction: Condition in which one tectonic plate plunges under another and is melted down into magma again. Subittoral: Lower division of sea from about 4m to 60m to below 200m. Subsidence: Sinking of land caused by collapse of underground mines or depletion of groundwater. Subsidy-stress gradient: Gradient of response of a system to a perturbation, either positive (in creased productivity) or negative (growth or reproductive retardation), through time. Subspecies: Geographical unit of a species population distinguishable by certain morphological behavioral or physiological characteristics. Succession: It is the natural replacement of one biotic community by another. The gradual change in plant and animal communities in an area following disturbance or the creation of new community. Succession has the following type such as: Allogeneic Succession = responding to habitat changes imposed by outside physical forces; antigenic Succession = from biological interactions within the ecosystem; primary Succession = on land never before vegetated; secondary Succession = on old habitat that has been devegetated. Suess effect: Reduced concentration of 14C in the atmosphere as a consequence of fossil fuel burning. Sulfur cycle: Transfer of sulfur, (S) Among the lithosphere (the dominant reservoir), the atmosphere, the hydrosphere, and the biosphere and also the transformations between various chemical forms Sulfur dioxide (SO2): Colorless gas produced during combustions of fossil fuels contaminated with organic and inorganic sulfur compounds. Can be converted into sulfuric acid in the atmosphere. Sulfur oxides (SO3): Sulfur and sulfur trioxide, common air pollutants arising from combustion of coal, oil, gasoline and diesel fuel. Also produced by natural sources such as bacterial decay and hot springs. Sulfur dioxide reacts with oxygen to from sulfur trioxide, which may react with water to form sulfuric acid. Sun plant: Plant capable to grow and reproduce only under high light conditions. Supension feeders: Living beings that take away particles of food from the water above the substrate. Supercooling: In ectoderms, lowering of body temperature below freezing without freezing body tissue; involves the presence of certain solutes particularly such as glycerol. Supply and demand theory: Economic theory explaining the price of goods and services. The supply of and demand for goods and services are primary price determinants. High demand diminishes supply, creating competition for existing goods and services, thus driving up prices. Surface mining: Any of several mining techniques in which all the dirt and rock overlying a desirable mineral (coal for example) are first removed, exposing the mineral. Surface runoff: Water flowing in streams and over the ground during rainstorm or snowmelt. Survival of the fittest: Darwin's model of evolution is known as ‘the survival of the fittest’. The idea ‘survival of fittest’ is the keystone of the theory of natural selection and the most important key factor. It has been declared that the process of natural selection soon became ‘survival of the fittest’. “The vigorous, healthy and happy survive and multiply (Darwin, 1859)”, and “a struggle for existence in which the weakest and the least perfectly organism must always surrender (Wallace, 1858)”. On the other hand, it has been confirmed that a great deal of mortality appears to be accidental and not a selection. Sometimes a large number of animals die due to natural hazards such as earthquake, flood, volcano etc. and a few lucky animals may survive. So, there is no chance for survival of the fittest. Survivorship curve: A graphical summary of patterns of survival in a population from birth to the maximum age attained by each individual. Ecologists have proposed that most survivorship curves fall into three major categories. A relatively high rate of survival among young and middle-aged individuals followed by a high rate of mortality among the aged is known as a type I survivorship curve. This is the pattern of survival as seen in populations of Dall sheep, P. drummondii, and rotifers. A constant rates of survival throughout life produce the straight-line pattern of survival known as a type II survivorship curve. American robins, white-crowned sparrows, and common mud turtles show this pattern of survival. A type III survivorship curve is one in which a period of extremely high rates of mortality among the young is followed by a relatively high rate of survival. The desert plant Cleome provides an excellent example of a type III survivorship curve. Sustainability: Ability to meet the needs of the present generation without compromising the ability to meet the needs of future generations, maintaining natural capital and resources to supply with necessities or nourishment to prevent falling below a given threshold of health or vitality Sustainable (use): The use of components of biological diversity in a way and at a rate that does not lead to the long-term decline of biological diversity. In other words it means utilization of resources without loss of native biodiversity and availability of resources as some level year after year. Sustainable ethics (mentality): A mind-set that views humans as a part of nature and earth as a limited supply of resources, which must be carefully managed to prevent, irreparable damage. Obligations to future generations require us to exercise restraint to ensure adequate resources and a clear environment. Sustainable society: It is based on sustainable ethics and lives within the limits imposed by nature. Sustainable society is based on maximum use of renewable resources, recycling, conservation, and population control. Sustained yield concept: Use of renewable natural resources, such as forests and grassland that will not cause their destruction and will ensure continued use. Sustained yield: Yield per unit time from an exploited population equal to production per unit time. Swamp: Wooded wetland in which water is close or on top of ground level. Switching: Predator changing its diet from a less plentiful to a more plentiful prey species (threshold of security). Symbiosis: Two or more dissimilar species living together in close association; which includes commensalisms (in which one is unaffected and the other aided) and mutualism ( in which both are helped). Symbiosis (cooperation) is an exceedingly widespread phenomenon; there is no major group of animals that does not include symbiotic species, and there is probably no individual animal that does not play host to at least one symbiotic process. Sympartic speciation: Formation of new species without geographical isolation; living in the same area. It describes the condition in which populations or species have overlapping geographic ranges. It is common in plants. Sympartic: Having overlapping distributions; occurring together in the same area. Synecology (community ecology): Study of groups of organisms in relation to their environment. Synergism: The acting of two or more agents (often toxins) together to produce an effect larger than expected based on knowledge of the effect of each alone. Synfuel: See synthetic fuel. Syngamy: The fusion of sex cells. Synthetic fertilizer: Same as inorganic fertilizer. Synthetic fuel: Gaseous or liquid organic fuel derived from coal, oil shale, or tar sands. Synthetic theory of evolution: The fusion of Darwinian Theory (natural selection) with: i) mutation; ii) population genetics; iii) principles of Mendelian genetics; and iv) molecular genetics is referred to as Neo-Darwinism or the Modern Synthetic (or the Modern Synthesis). The theoretical basis of role of inheritance in evolution was advanced by the mathematicians- Fisher (1930), Haldene (1930, 1954) and Wright (1931) who developed population genetics (study of allele frequencies and genotype or variation in breeding population). After that the geneticist Dobzhansky (1937), the biologist Huxley (1942), the systematic ornithologist Mayer (1942) and the palaeontologist Simpson (1953) did major works and showed how Mendelism and Darwinism were indeed compatible and they finally synthesized the neo-Darwinian theory of evolution. System: Collection of interdependent components functioning within a defined boundary; the outside environment provides both inputs and receives attributes transmitted to it by the system. Systematics: The study of the historical evolutionary and genetically relationships among organisms and of their phenotypes similar and differences. Systems ecology: The branch of ecology focusing on general complex systems theory and application, such as the dynamics of forests, with mathematical models based on simulation models, using a digital computer. T Taiga: Boreal forest; Biome found south of the tundra across North America, Europe, and Asia, characterized by coniferous forests. Though dominated by coniferous trees they also contain aspen and birch. In this forest high species diversity is found. Tannins: Compounds serving plants as quantitative defenses that make tissues indigestible. Tar sands: Also known as oil sands or bituminous sands. Sand impregnated with viscous, petroleum like substance, bitumen, which can be driven off by heat, producing synthetic oil. Taxon cycle: Selection series on islands as K-strategists evolve fro colonists, followed by rselection among island endemics. It is a unit (e.g. honey bee) of classification to which individuals, or sets of species assigned. Taxon (pl. taxa): A taxonomic group that is distinct enough to be assigned a name and placed in an official taxonomic category. Technoecosystem: A human-built scheme such as city, sub-city, and industrial development Technological fix: A purely technological answer to a problem. Also called a technical fix. Tectonic plates: Huge segments of the earth's crust that often contains entire continents or parts of them and that float on an underlying semi-liquid layer. Teleology: The doctrine that developments are due to the purpose that is served by them. Teleology (Telos means direction, purpose or goal) is a form of reasoning that finds a purpose and a design in nature. Teleology (natural law) as well as all known natural processes, living or otherwise a starting condition directed toward a given terminal condition (end point), because the starting object has built into a supernatural fore-knowledge of what the end condition is to be. For example, developing eggs behave as if they knew what plan of the adult is to be. A chicken embryo soon produces two wings, as if it knew that these appendages are to be part of an adult. Clearly, this and all other forms of teleology explain an end state by simply declaring it is given at the beginning. Temperate forest (or temperate deciduous forest): Biome located in the eastern United States, Europe, and northeastern China below the taiga. This biome is characterized by deciduous and nondeciduous trees, warm growing season, abundant rainfall and rich species diversity. This forests generally is found where annual precipitation averages anywhere from about 650 mm to over 3000 mm and receives more winter precipitation than temperate grasslands. Temperate grassland: Biomes governed by grasses (such as Andropogon, Panicum and Bouteloua) in middle latitudes that receive between 300 and 1000 mm per year precipitation, with maximum precipitation usually falling during the summer months. Temperate rain forest: Forests in regions differentiated by a comparatively mild climate and heavy rainfall that produces luxurious vegetative growth. This forest is usually including numerous kinds of trees and distinguished from topical rain forest by the presence of a dominant tree species. One best example is the coniferous forest of the coastal pacific northwest of North America. Temperate woodland and shrub land: A biome associated with mild, moist winter conditions and usually with dry summers between about 300 and 400 latitude. The vegetation of this biome is usually characterized by small, tough (sclerophyllous) leaves and adaptations to periodic fire. This biome is found around the Mediterranean Sea and in western North America, Chile, southern Australia, and southern Africa. Temperature inversion: Alternation in the normal atmospheric temperature profile so that air temperature increases with attitude rather than decreases. Temperature profile: The relationship of temperature to depth below the surface of water or the soil, or the height above ground. Temporary threshold shift: Momentary dulling of the sense f hearing after exposure to loud sounds. Can lead to permanent threshold shift. Tensile strength: Force required breaking a material, such as a bone or tendon. Teratogen: A chemical or physical agent capable of causing birth defects. Terracing: Construction of small earthen embankments on hilly or mountainous terrain to reduce the velocity of water flowing across the soil and reduce soil erosion. Territorial signals: The ways in which territory owners declare their ownership. Territory: An area occupied by an animal or group of animals and defended against other of the same species. Tertiary treatment (of sewage): Removal of nitrates, phosphates, chlorinated compounds, salts, acids, metals, and toxic organics after secondary treatment. Tertiary: The first and longest period of the Cenozoic, starting some 65 million years ago and ending 2 million years ago; composed of Paleocene, Eocene, Oligocene, Miocene and Pliocene epochs; characterized by emergence of mammals. Tetreaploid: Having four sets of chromosomes in undifferentiated cells. Thermal conductance: Rate at which heat flows through a substance. Thermal neutral zone: The range of environmental temperatures over which metabolic rate of a homoeothermic animal does not vary with temperature. Thermal pollution: Heat added to air or water that adversely affects living organisms and may alter climate. Thermal tolerance: Range of temperatures in which an aquatic poikilothermic is most to home. Thermocline: A depth zone in a lake or ocean through which temperature changes with depth, generally about 10C per meter of depth; zone of water in a thermally stratified lake between the epilimnion and hypolimnion. Thermogenesis: Enhance in production of metabolic heat to counteract the deficit of heat to a colder environment. Thermophilic: A term applied to organisms that tolerate or require high-temperature environments. Thermosphere: The outer layer of the earths’ atmosphere beginning approximately 80 km above the earth's surface. Therophyte: Life form of plants that survives adverse conditions in the form of a seed; which may be an annual and a short-lived species. Third generation pesticides: Newer chemical agents to control pests, such as pheromones and insect hormones. Threatened species/ communities: Hundreds of microscopic and small sized species of both flora and fauna have become extinct due to unplanned urbanization and implementation of modern agronomical practices. So, targeted action is needed to bring threatened species and ecological communities back from the edge of extinction. The vigor for fuel yielding wood and for extra-grazing of livestock needs to be restricted for a strong protection of ecological niches in all area. Threshold level: A level of exposure below, which no effect is observed or measured. Threshold of security: Point in local population mass at which the predator turns its awareness to other prey because of harvesting efficiency. It is the section of prey population below the threshold is comparatively safe from predation. Throughput approach: A method of solving an environmental problem by recycling and reuse. For example, recycling or reusing hazardous wastes reduces their output. Tilth: Aggregation of mycorrhizae and soil particles that constitutes a healthy soil structure. Time lag: Delay in response to a change. Time preference: A measure of the value of an immediate gain in comparison with a long-term gain. Time stability: Hypothesis that places with stable and permanent physical environments. Tolerance model: A model of succession that proposes the succession guides to a community, in which initial stages of colonization are not limited to a few pioneer species, the juveniles species dominating at climax that can be present from the earliest stages of succession, and species colonizing early in succession do not facilitate colonization by species characteristic of later successional stages. Later successional species are simply those tolerant of environmental conditions early in succession. Top-down control (or regulation): Regulation of a community or ecosystem trophic structure by increased predation; influence of secondary consumers on the sizes of the trophic levels below them in the food web. Topography: Characteristics of the ground surface in regard to physical features. Toposequence: Pattern of native soils whose development was controlled by topography of landscape. Torpidity: Temporary of an animal involving a great reducing in loss of ability of movement and feeling; usually occurs in response to some adverse environmental state such as heat or cold to decrease energy spending. Torpor: A state of low metabolic rate and lowered body temperature. During torpor, a hummingbird’s body temperature is about 120 to 170C, quite a reduction from 390 C. Because this lower body temperature is a direct consequence of a lower metabolic rate, hummingbirds in torpor save a great deal of energy. Total fertility rate: Average number of children that would be born alive to a woman if she were to pass through all her childbearing years conforming to the age specific fertility rates of a given year. Toxin: A chemical, physical, or biological agent that causes disease or some alteration of the normal structure and function of an organism. Impairments may be slight or severe. Onset of effects may be immediate or delayed. Trace element: Element occurring and needed in minor quantities. Trandisciplinary: Refers to approaches involving multilevel large-scale cooperation focusing on entire educational or innovative systems. Translocation: Transport of materials within plant. Minerals are absorbed by plant from soil into roots and their movement is happen throughout the plant. Transpiration efficiency: Ratio of net main production to water transpired conduct experimental action designed to create an effect. Transpiration: Loss of water vapor by land plants; chiefly through the tiny pores (stomata) in the leaves through which carbon dioxide enters. Transported soil: Soil developed at a distant site from its parent materials. Trapline: To go a long a usual way while harvesting scattered resources. Tree farms: Private forests devoted to maximum timber growth and lying heavily on herbicides, insecticides, and fertilizers. Triassic oldest: Period of the Mesozoic some 230 to 195 million years ago; rise in ancient amphibians and reptiles found in this period. Tritium (hydrogen-3): Radioactive isotope of hydrogen whose nuclease contains two neutrons and one proton. Can be used in fusion reactors. Trophic (feeding) biology: The study of the feeding biology of organisms. Trophic dynamics: Transfer of energy from one trophic level (or part of an ecosystem) to another (for example, primary producer to secondary consumer); functional classification of organisms in an ecosystem according to feeding relationships. Trophic height: Considered 1 plus the length in the logic of ecological efficiencies of the shortest food chain linking a species to a primary producer. Trophic level: Feeding level; working categorization of organisms in an ecosystem according to feeding relationships. For instance primary producer, primary consumer, secondary consumer, tertiary consumer, and so forth. Trophic niche: Working rank of a species based on trophic level or energy association. Trophic structure: The organization of a community in trophic levels based on the number of feeding or energy shift levels. Trophic: Related to feeding. Trophogenic zone: Higher layer of the water line in lakes, ponds, and oceans in which light are satisfactory for photosynthesis. Tropholytic zone: Area in lakes and oceans below the compensation point Tropical dry forest: A broadleaf deciduous forest growing in tropical regions having pronounced wet and dry seasons; trees drop their leaves during the dry season. Tropical rain forest: A broad leaf evergreen forest growing in tropical regions where conditions are warm and wet year-round. Tropical savanna: Tropical grassland scattered with scattered trees, which is characterized by pronounced wet and dry seasons and periodic fires. Troposphere: A layer of the atmosphere extending from the earth's surface to an altitude of 9 to 16 km. Trypanosoma: Parasitic protozoan of the genus Trypanosoma. At one stage of their life cycle, they are slender, more or less pointed at both ends, and on one end bear a long slender process known as a flagellum, with which they pull themselves along. Tsetse fly: A fly of the genus Glossina (Muscidae). Endemic to Africa tsetse flies are ferocious, tough bloodsuckers that convey human sleeping sickness and nagana, both caused by trypanosomes. Tuckfield: Maxim data collected for a common or unspecified reason can reply very few specific questions. Tundra: Areas in arctic and alpine (high mountains) regions which is characterized by lack of trees, and growth of mosses, lichens, sedges, forbs, dwarf willows, and low shrubs. This tundra receives low to moderate precipitation and having a very short growing season. Turbidity: A condition in air or water that reduces the transparency. Turgor pressure: Pressure of the cell against its cell wall as the result of water moving by osmosis into the cell from outside. This pressure gives non-woody parts of a plant most of their firmness. Turnover rate: Rate of replacement of a substance or a species when losses to a system are replaced by additions. Turnover time: Time needed to replace a amount of a matter or resource equal to the amount of that component present in the system. Twin-berry: Lonicera involucrata (Caprifoliaceae), the busy relative of the honeysuckle that serves as larval food plant for Gillette's checkerspot. Tyrannosaurus: The largest and most impresive predatory dinosaur. This creature which stood 6m high and weighed about 8 tons, lived some 70 million years ago. U Ultimate factors: Aspects of the environment those are directly important to the well being of an organism (for example, food). Its opposite phrase is proximate factors Ultimate incipient lethal temperature: Upper or lower limit of temperature at which an adapted organism will surrender. Ultimate production: Total amount of a nonrenewable resource that could ultimately be extracted at a reasonable price. Ultraviolet (UV) light or radiation: Electromagnetic radiation at wavelengths between 100 and 400 nanometers, from sun and special lamps. Causes sunburn and mutations in bacteria and other living cells. Undernourishment: A lack of calories in the diet. Understory: Layer of vegetation below the canopy of forest. Ungulate: A hoofed animal, such as horses, cattle, elephants, rhinos and pigs. Univoltine: Breeding only once in a season. Unstable equilibrium: The particular state of a system upon which forces are precisely balanced, but away from the system moves when displaced. Upwelling: Movement of deeper ocean water to the surface; occurs most commonly along the west coasts of continents. For example the Peru Current along the coast of South America and around Antarctica. V Vacuole: Fluid-filled cavity within the cytoplasm. Vagile: Free to move about. Vagility: Intrinsic ability to move about freely. Validation: An explicit and objective test of the basic hypothesis. Vapor pressure deficit: The difference between the actual vapor pressure and the saturation water vapor pressure at a particular temperature. Vapor pressure: The amount of pressure water vapor exerts independent of dry air. Variance: The square of the standard deviation. Variation: Genetically based differences in behavior, structure or function in a population. Variation: Living organisms differ distinctly from their parents or allied species are known as variation. Variation is the raw materials of evolution and there are two kinds of variations, continuous and discontinuous. Continuous variations are the main causes of origin of species (evolution). But according to modern evolutionist, continuous phenotypic variations (acquired variation) are not inherited and had no importance in evolution. Conversely, discontinuous variations (mutations) are only important for evolution. Vector: Organism that transmits a pathogen from one organism to another Vegetative reproduction: Asexual reproduction in which plants breed themselves by means of specialized multicultural organs such as bulbs, corms, rhizomes, stems, and the like. Verification: Process of testing whether or not a model is practical representation of a real-life system being investigated. Vernal pool: Temporary pond or shallow lake (pool) filled in the spring. Vesicle: Storage organ in vesicular-arbuscular mycorrhizal fungi. Vesicular-arbuscular mycorrhizae (VAM): Association between fungal mycelia and plant roots, in which the fungus approaches and grows within the root cells of the host and extends into the surrounding soil. Vicariance biogeography: Biogeography focused on the growth of barriers chiefly by plate tectonic processes. Virulence: The aspect of parasites that determines the harm done to the host. Viscosity: Property of a fluid that resists the force within the fluid that causes it to flow. Vital rates: Birth and death rates. Volterra principle: The scheme that if some factor causes equal rises in death rates in both predators and prey in a predator-prey system, the predator population size will drop excessively. Vulnerable Species: Species whose population numbers are decreasing so that they are likely to become more severely threatened with time in near future. W Walker circulation: A large-scale atmospheric circulation that moves in the plane of the equator. Wallace's line: Biogeographic line between the islands of Borneo and the Celebes, which marks the eastward boundary of many land locked Eurasian organisms and the boundary of the oriental region. Water cycle: Hydrological cycle. Water logging: High water table causing saturation of soils due to poor soil drainage and irrigation. Decreases soil oxygen and kills plants due to water logging condition. Water potential: Capacity of water to perform work, which is determined by its free energy content. Increase of solute concentration decrease water potential. Water potential is also known as the chemical potential of water. Water relation: How organisms balance water losses to the environment with water intake. Water table: Top of the zone of saturation. Water vapor: The atmospheric pressure exerted by the water vapor in air. This pressure increases as the water vapor in air increases. Watershed: The total land area-contributing surface or ground water to a lake, river, or drainage basin that contributes water to the flow at that point. It is a topographic dividing line from which surface streams flow in two different directions. Watt: Unit of power indicating rate at which electrical work is being performed. Wave power: Energy derived from sea waves. Wave-generated succession: Secondary succession started in plant communities susceptible to strong winds when waves of trees or plants are uprooted. Wet cooling tower: Device used for cooling water from power plants. Hot water flows through rising air, which draws off heat. Cool water is then returned to the system. Wetlands habitats: Those are continually or occasionally flooded. Wetlands: Land areas along fresh water (inland wetlands) and salt water (coastal wetlands) that are flooded all or part of the time. In simple words land areas those are continually or occasionally flooded. Whiptail-lizard: A new world lizard of the genus Cnemiddophous (Teiidae) characterized by a slender, whip like tail Wild type: The commonest phenotype, genotype or allele of a species. Wilderness area: An area established by the U.S. Congress under the Wilderness Act (1964) where timber cutting and use of motorized vehicles are prohibited. Most areas are located in national forests. Wilderness: An area where the biological community is relatively undisturbed by humans; seen by developers as an untapped supply of resources such as timber and minerals, seen by environmentalists as a haven for escape from hectic urban life, an area for reflection and solitude. Wildfires: Intense fires that destroy most of the plants and some soil natural matter. Wildlife management: The branch of ecology dealing with the management and protection of native wildlife. Wildlife sanctuary: This phrase is similar to a National Park. It is devoted to protect wildlife, but it considers the conservation of species only and its boundary is not limited by state legislation. Wilting point: Moisture content of soil on an oven-dry basis at which plants wilt and unsuccessful to recover their turgidity when placed in a moist atmosphere. Wind energy: Energy captured from the wind to generate electricity or pump water. An indirect form of solar energy. Wind generators: Windmills that produce electrical energy. Woodland: Tree-covered land counting associated plant and animal homes. X Xerarch succession: Progression of terrestrial plant communities developing in habitats with well-drained soil. Xeric: An environment, in which production by green plants is limited by lack of water (dry condition), especially relating to soil. Xerophile: Drought-loving plant. The term is used for xerophytes by De Condolle in 1874. Xerophytes: Plants adapted to live in a dry or physiologically dry (saline) habitat for surviving prolonged periods of drought e.g., cacti. Xerosere: Term applies to explain succession on dry land or rock surface. Y Yield output or return: Generally expressed in energy or bulk of natural resource such as fish, timber etc from water or terrestrial ecosystem. Z Zebu cattle: An Asiatic type of cattle with a humped-back and large dewlap. It is fairly resistant to heat and insect attack. Zeitgeber: Time-setter, generally light that entrains a circadian rhythm to environmental regularity. Zero population growth: A condition in which population is not increasing; the population growth rate is zero. Zonation: Distribution of flora along an environmental grade (or zones), such as latitudinal, altitudinal, or horizontal zones within a countryside zone of the oceans. Zoo: Zoo is known as zoological garden or zoological park. It plays a role in the conservation of threatened or endangered animals by developing innovative breeding programs to maintain populations of species that are in decline. It is devoted to the exhibition, preservation and study of animals. It also educates the public about animal behavior. Zoogeography: The science of science which dealing with the geographic distribution of animals. Zooplankton (Planktonic animals): Floating or weakly swimming an animal in marine and freshwater ecosystems; most zooplankton are microscopic. Zygote: The diploid cell resultant from the union of two haploid gametes, i.e. the fertilized egg.