Palaeontographica Abteilung A-palaozoologie-stratigraphie, Oct 26, 2006
Abstract The Indian fossil vertebrate record from the Mid-Late Cretaceous to the Early Eocene is ... more Abstract The Indian fossil vertebrate record from the Mid-Late Cretaceous to the Early Eocene is now becoming better known and can be used to document the northward drift of the landmass in terms of response of non-marine and near-shore vertebrate faunas. The ...
A collection of Tertiary fishes and molluscs from the Kuksho Formation of the Indus Group near Ny... more A collection of Tertiary fishes and molluscs from the Kuksho Formation of the Indus Group near Nyoma, Ladakh are described, The fish families represented are: Siluridae, Channidae and Cyprinidae. The fishes are associated with dextrally coiled gastropods and unionid pelecypods.
Journal of The Geological Society of India, Sep 1, 2004
The Kasauli Formation represents the initial stage of development of the foreland basin in respon... more The Kasauli Formation represents the initial stage of development of the foreland basin in response to the rising Himalaya. Here we report for the first time, a mammal (Rhinoceratidae, gen. et sp. indet) and some new taxa of fossil flowers from two localities, Shiv Mandir and Water Tank. The Kasauli Formation comprises of a grey/green, sometimes highly carbonaceous shale and massive grey/green sandstone sequence which so far has lacked an age-diagnostic biotic assemblage. The presence of a rhinoceratid, commonly known from other coeval sections of the Lower Murree in Pakistan and the Kalakot region, suggests the potential of finding suitable palaeontological temporal constraints for the fossil-bearing horizons. Two new taxa of fossil flowers, Kasaulipushpam and Trilobanthus are described. The present data suggests the presence of a well-watered landscape during Kasauli times in sharp contrast to more arid condition in the underlying Dagshai Formation which is predominantly red in colour.
Palaeontology tries to answer questions that are basic to our existence: How did life come into b... more Palaeontology tries to answer questions that are basic to our existence: How did life come into being and how did it develop mechanisms to sense the world in which we live and then make living duplicates of ourselves. Some of these phenomenon are preserved in rocks as fossils and it is the palaeontologist’s joy and duty to dig these out from the rock and interpret them in terms of science. Take for example the subject that drew me to this discipline, namely the evolution of sight.
Collagens are the most abundant proteins in the animal kingdom. They form the structural framewor... more Collagens are the most abundant proteins in the animal kingdom. They form the structural framework of connective tissues such as bones, tendons and skin, and play an important biomechanical role in supporting tissue functions. The preservation of collagen in deep time is a topic of intense debate. Here we provide indisputable evidence for the presence of collagen in early Eocene fish vertebrae using online pyrolysis comprehensive two dimensional gas chromatography time-of-flight mass spectrometry (py-GC9GC-TOFMS) and immunofluorescence analysis. The presence of cyclic dipeptides such as diketodipyrrole, 2,5-diketopiperazine of proline-proline and 2,5-diketopiperazine of proline-glycine along with other nitrogen-bearing
The discovery of Precambrian microfossils in 1954 opened a new vista of investigations in the fi ... more The discovery of Precambrian microfossils in 1954 opened a new vista of investigations in the fi eld of evolution of life. Although the Precambrian encompasses 87% of the earth's history, the pace of organismal evolution was quite slow. The life forms as categorised today in the three principal domains viz. the Bacteria, the Archaea and the Eucarya evolved during this period. In this paper, we review the advancements made in the Precambrian palaeontology and its contribution in understanding the evolution of life forms on earth. These studies have enriched the data base on the Precambrian life. Most of the direct evidence includes fossil prokaryotes, protists, advanced algal fossils, acritarchs, and the indirect evidence is represented by the stromatolites, trace fossils and geochemical fossils signatures. The Precambrian fossils are preserved in the form of compressions, impressions, and permineralized and biomineralized remains. [Sharma M and Shukla Y 2009 The evolution and distribution of life in the Precambrian eon-Global perspective and the Indian record; J. Biosci. 34
Memoirs of the Faculty of Science, Kyoto University. Series of geology and mineralogy, Aug 15, 1971
A new species of a shark, Ctenacanthus ishii is described on the basis of an isolated tooth from ... more A new species of a shark, Ctenacanthus ishii is described on the basis of an isolated tooth from the Zewan Series of Guryul Ravine, Kashmir. The tooth of Ctenacanthus ishii is characterized by eight subsidiary cusps and an elevated cusp. The central cusp is oriented at right angle to the basal plate. Of the subsidiary cusps, the extreme lateral pair is the largest (approximately 1/3 ofcentral cusp) and is situated at the labial extremity ofthe tooth making an angle of 1 150 with the base. The root plate is reniform with the labial border almost straight and the lingual side convex. The find of a shark tooth in the marine Perrnian beds of Kashmir is significant considering the rarity of fossil vertebrates in the Palaeozoics of the Himalayas.
... Teeth with smooth surfaces resemble those of the Late Cretaceous-Early Palaeocene Takli Forma... more ... Teeth with smooth surfaces resemble those of the Late Cretaceous-Early Palaeocene Takli Formation of Nagpur (Rana, 1984). Order Saurischia Page 8. 12 GVR PRASAD AND ASHOK SAHNI Family Megalosauridae gen. & sp. indet. ...
In India, Cretaceous elasmobranchs are known from the uppermost Cretaceous Deccan intertrappean s... more In India, Cretaceous elasmobranchs are known from the uppermost Cretaceous Deccan intertrappean sedimentary sequences of peninsular India and the lower Upper Cretaceous (Cenomanian) Karai Formation of the Cauvery basin, South India. The intertrappean elasmobranchs are represented mainly by rays and skates, whereas the Karai fauna is known by hexanchiform, squaliform, and lamniform sharks. The latter assemblage is dominated by cool temperate water forms in addition to some cosmopolitan forms. Here new shark teeth recovered from the upper part of the marine Cretaceous Bagh Group, in the lower Narmada valley, Western India are described. This is the first detailed description of sharks from the Bagh Group and the first record of sharks from the youngest horizons (Coniacian to Late Maastrichtian) of this marine sedimentary sequence. The fauna, recovered from an oyster shell-rich green sandstone at the top of the youngest geological unit (the Coralline Limestone) of the Bagh Group, is assigned to Ptychodus sp., Scapanorhynchus sp. aff. S. raphiodon (Agassiz, 1844), Cretodus sp. aff. C. crassidens (Dixon, 1850), Cretalamna sp., Squalicorax sp. aff. S. falcatus Agassiz, 1843, and Elasmobranchii indet. This assemblage, previously widely documented from the Cretaceous deposits of North and South Americas, Europe, North and West Africa, Far East and Near East, demonstrates that there is a clear change in elasmobranch faunal composition of India from cool temperate water forms in the early Late Cretaceous to essentially cosmopolitan forms in the Late Cretaceous.
Taphonomy. a sub-branch of palaeontology, is defined as the study of the sequence of events begin... more Taphonomy. a sub-branch of palaeontology, is defined as the study of the sequence of events beginning with the death of an organism and its subsequent deposition and fossilization. The present paper outlines imponant areas in which the work ha..' been done on this subject and also attempts to review the Indian contributions. The conditions of the burial and the preservation of nests and eggshell fragments of dinosaurs provide ample for taphonomic analysis. There is a need for experimental study on dispersal. disintegration, preservation and diagenesis of organic fossils. In puts from sedimentology are essentiaJ and only an interdisciplinary effon can result in any success to build the postrnonem history of plants and animals.
The Vastan Lignite Mine, situated about 30 km northeast of Surat in Gujarat, preserves a fairly c... more The Vastan Lignite Mine, situated about 30 km northeast of Surat in Gujarat, preserves a fairly continuous record of near shore lignites interbedded with lagoonal and open marine sediments bearing foraminifera and molluscs. This paper reports a teredo-infested fossil dicotyledonous wood belonging to Family Meliaceae from the carbonaceous shale sequence near the top of the Lower Eocene section. The wood is well preserved and shows resemblance with the extant woods of the genus Aglaia Lour. The presence of wood suggests a fluvial transport from its natural habitat of an inland moist tropical forest to a nearby coastal region. The profuse infestation of the wood by teredos further indicates considerable exposure before burial probably in a near shore lagoon or tidal flat area where it was bored by Teredolites.
Palaeontographica Abteilung A-palaozoologie-stratigraphie, Oct 26, 2006
Abstract The Indian fossil vertebrate record from the Mid-Late Cretaceous to the Early Eocene is ... more Abstract The Indian fossil vertebrate record from the Mid-Late Cretaceous to the Early Eocene is now becoming better known and can be used to document the northward drift of the landmass in terms of response of non-marine and near-shore vertebrate faunas. The ...
A collection of Tertiary fishes and molluscs from the Kuksho Formation of the Indus Group near Ny... more A collection of Tertiary fishes and molluscs from the Kuksho Formation of the Indus Group near Nyoma, Ladakh are described, The fish families represented are: Siluridae, Channidae and Cyprinidae. The fishes are associated with dextrally coiled gastropods and unionid pelecypods.
Journal of The Geological Society of India, Sep 1, 2004
The Kasauli Formation represents the initial stage of development of the foreland basin in respon... more The Kasauli Formation represents the initial stage of development of the foreland basin in response to the rising Himalaya. Here we report for the first time, a mammal (Rhinoceratidae, gen. et sp. indet) and some new taxa of fossil flowers from two localities, Shiv Mandir and Water Tank. The Kasauli Formation comprises of a grey/green, sometimes highly carbonaceous shale and massive grey/green sandstone sequence which so far has lacked an age-diagnostic biotic assemblage. The presence of a rhinoceratid, commonly known from other coeval sections of the Lower Murree in Pakistan and the Kalakot region, suggests the potential of finding suitable palaeontological temporal constraints for the fossil-bearing horizons. Two new taxa of fossil flowers, Kasaulipushpam and Trilobanthus are described. The present data suggests the presence of a well-watered landscape during Kasauli times in sharp contrast to more arid condition in the underlying Dagshai Formation which is predominantly red in colour.
Palaeontology tries to answer questions that are basic to our existence: How did life come into b... more Palaeontology tries to answer questions that are basic to our existence: How did life come into being and how did it develop mechanisms to sense the world in which we live and then make living duplicates of ourselves. Some of these phenomenon are preserved in rocks as fossils and it is the palaeontologist’s joy and duty to dig these out from the rock and interpret them in terms of science. Take for example the subject that drew me to this discipline, namely the evolution of sight.
Collagens are the most abundant proteins in the animal kingdom. They form the structural framewor... more Collagens are the most abundant proteins in the animal kingdom. They form the structural framework of connective tissues such as bones, tendons and skin, and play an important biomechanical role in supporting tissue functions. The preservation of collagen in deep time is a topic of intense debate. Here we provide indisputable evidence for the presence of collagen in early Eocene fish vertebrae using online pyrolysis comprehensive two dimensional gas chromatography time-of-flight mass spectrometry (py-GC9GC-TOFMS) and immunofluorescence analysis. The presence of cyclic dipeptides such as diketodipyrrole, 2,5-diketopiperazine of proline-proline and 2,5-diketopiperazine of proline-glycine along with other nitrogen-bearing
The discovery of Precambrian microfossils in 1954 opened a new vista of investigations in the fi ... more The discovery of Precambrian microfossils in 1954 opened a new vista of investigations in the fi eld of evolution of life. Although the Precambrian encompasses 87% of the earth's history, the pace of organismal evolution was quite slow. The life forms as categorised today in the three principal domains viz. the Bacteria, the Archaea and the Eucarya evolved during this period. In this paper, we review the advancements made in the Precambrian palaeontology and its contribution in understanding the evolution of life forms on earth. These studies have enriched the data base on the Precambrian life. Most of the direct evidence includes fossil prokaryotes, protists, advanced algal fossils, acritarchs, and the indirect evidence is represented by the stromatolites, trace fossils and geochemical fossils signatures. The Precambrian fossils are preserved in the form of compressions, impressions, and permineralized and biomineralized remains. [Sharma M and Shukla Y 2009 The evolution and distribution of life in the Precambrian eon-Global perspective and the Indian record; J. Biosci. 34
Memoirs of the Faculty of Science, Kyoto University. Series of geology and mineralogy, Aug 15, 1971
A new species of a shark, Ctenacanthus ishii is described on the basis of an isolated tooth from ... more A new species of a shark, Ctenacanthus ishii is described on the basis of an isolated tooth from the Zewan Series of Guryul Ravine, Kashmir. The tooth of Ctenacanthus ishii is characterized by eight subsidiary cusps and an elevated cusp. The central cusp is oriented at right angle to the basal plate. Of the subsidiary cusps, the extreme lateral pair is the largest (approximately 1/3 ofcentral cusp) and is situated at the labial extremity ofthe tooth making an angle of 1 150 with the base. The root plate is reniform with the labial border almost straight and the lingual side convex. The find of a shark tooth in the marine Perrnian beds of Kashmir is significant considering the rarity of fossil vertebrates in the Palaeozoics of the Himalayas.
... Teeth with smooth surfaces resemble those of the Late Cretaceous-Early Palaeocene Takli Forma... more ... Teeth with smooth surfaces resemble those of the Late Cretaceous-Early Palaeocene Takli Formation of Nagpur (Rana, 1984). Order Saurischia Page 8. 12 GVR PRASAD AND ASHOK SAHNI Family Megalosauridae gen. & sp. indet. ...
In India, Cretaceous elasmobranchs are known from the uppermost Cretaceous Deccan intertrappean s... more In India, Cretaceous elasmobranchs are known from the uppermost Cretaceous Deccan intertrappean sedimentary sequences of peninsular India and the lower Upper Cretaceous (Cenomanian) Karai Formation of the Cauvery basin, South India. The intertrappean elasmobranchs are represented mainly by rays and skates, whereas the Karai fauna is known by hexanchiform, squaliform, and lamniform sharks. The latter assemblage is dominated by cool temperate water forms in addition to some cosmopolitan forms. Here new shark teeth recovered from the upper part of the marine Cretaceous Bagh Group, in the lower Narmada valley, Western India are described. This is the first detailed description of sharks from the Bagh Group and the first record of sharks from the youngest horizons (Coniacian to Late Maastrichtian) of this marine sedimentary sequence. The fauna, recovered from an oyster shell-rich green sandstone at the top of the youngest geological unit (the Coralline Limestone) of the Bagh Group, is assigned to Ptychodus sp., Scapanorhynchus sp. aff. S. raphiodon (Agassiz, 1844), Cretodus sp. aff. C. crassidens (Dixon, 1850), Cretalamna sp., Squalicorax sp. aff. S. falcatus Agassiz, 1843, and Elasmobranchii indet. This assemblage, previously widely documented from the Cretaceous deposits of North and South Americas, Europe, North and West Africa, Far East and Near East, demonstrates that there is a clear change in elasmobranch faunal composition of India from cool temperate water forms in the early Late Cretaceous to essentially cosmopolitan forms in the Late Cretaceous.
Taphonomy. a sub-branch of palaeontology, is defined as the study of the sequence of events begin... more Taphonomy. a sub-branch of palaeontology, is defined as the study of the sequence of events beginning with the death of an organism and its subsequent deposition and fossilization. The present paper outlines imponant areas in which the work ha..' been done on this subject and also attempts to review the Indian contributions. The conditions of the burial and the preservation of nests and eggshell fragments of dinosaurs provide ample for taphonomic analysis. There is a need for experimental study on dispersal. disintegration, preservation and diagenesis of organic fossils. In puts from sedimentology are essentiaJ and only an interdisciplinary effon can result in any success to build the postrnonem history of plants and animals.
The Vastan Lignite Mine, situated about 30 km northeast of Surat in Gujarat, preserves a fairly c... more The Vastan Lignite Mine, situated about 30 km northeast of Surat in Gujarat, preserves a fairly continuous record of near shore lignites interbedded with lagoonal and open marine sediments bearing foraminifera and molluscs. This paper reports a teredo-infested fossil dicotyledonous wood belonging to Family Meliaceae from the carbonaceous shale sequence near the top of the Lower Eocene section. The wood is well preserved and shows resemblance with the extant woods of the genus Aglaia Lour. The presence of wood suggests a fluvial transport from its natural habitat of an inland moist tropical forest to a nearby coastal region. The profuse infestation of the wood by teredos further indicates considerable exposure before burial probably in a near shore lagoon or tidal flat area where it was bored by Teredolites.
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