Papers by pierre Jouventin
HAL (Le Centre pour la Communication Scientifique Directe), Jan 17, 2022
P. Parey eBooks, 1982
Abstract 1. Compared the sexual and aggressive behavior of all genera of penguins to determine th... more Abstract 1. Compared the sexual and aggressive behavior of all genera of penguins to determine the biological meaning of ritualized attitudes. Optical and vocal signals are also investigated, and the evolution of penguin behavior is dealt with, along with ...
Evolutionary Ecology Research, 2006
Hypothesis: Colourful ornaments reveal an individual's immunocompetence, allowing birds to choose... more Hypothesis: Colourful ornaments reveal an individual's immunocompetence, allowing birds to choose mates on the basis of these characters. Organism: King penguins, Aptenodytes patagonicus. Field site: Colony of approximately 16,000 breeding pairs on Possession Island in the Crozet Archipelago, southern Indian Ocean. Methods: We measured foot-web swelling in males resulting from experimental injection of a novel mitogen (phytohaemagglutinin, PHA) and compared that measure of immunocompetence with colours of the beak spot and plumage. Conclusions: Breast plumage colour is a reliable indicator of immunocompetence in king penguins. Breast plumage colour appears to rely on the presence of pterin pigments, and the fact that pterins are implicated in immune function may underlie the honesty of this signal.
Revue D Ecologie-la Terre Et La Vie, 1981
Megadyp tes an tipodes EudypteS robus eus Eudyptes pachyrhynchus Eudyp tula minor minor Eudyp cut... more Megadyp tes an tipodes EudypteS robus eus Eudyptes pachyrhynchus Eudyp tula minor minor Eudyp cuta minor iredalei
Revue D Ecologie-la Terre Et La Vie, 1997
Animal Behaviour, Apr 1, 2003
Oecologia, 1993
Demographic parameters were estimated for snow petrels Pagodroma nivea nesting at Pointe G6ologie... more Demographic parameters were estimated for snow petrels Pagodroma nivea nesting at Pointe G6ologie Archipelago, Ad61ie Land, Antarctica between 1963 and 1990; 21 years of data on adult survival and 27 years of data on breeding success are available. The average age of first return and first breeding were 8.1 and 9.9 years respectively and there was no significant difference between the sexes. The overall breeding success averaged 51.3% and was very variable between years (21-80%). Breeding failure was mostly due to incubation failure and annual breeding success was negatively correlated with average snow falls in October-November and October-March. Breeding frequency was very low, averaging 52% of seasons during a reproductive lifetime. Good quality sites, with high occupancy rate and high breeding success were few in the study plots.
Some penguin species are shy because they were threatened by human activities. Species typically ... more Some penguin species are shy because they were threatened by human activities. Species typically differ in head pattern and by voice. On land, head pattern and voice influence mate choice by reflecting species, sexual maturity, and body condition. They act as ethological mechanisms of reproductive isolation, each species being adapted to a special mass of water, with unique temperature and salinity. Speciation in penguins depends both on distances among islands (geographical speciation) and on the sea temperature of the water mass (oceanographic speciation). As recent DNA analyses revealed and behavioral studies suggested more than 35 years ago, populations of pelagic feeding Rockhopper penguins have diverged in water masses of different temperatures. Thus, oceanographic speciation was a major factor producing new species. Contrarily, Gentoo penguins are coastal feeders, and geographic speciation has produced divergent and distant populations. So new species are likely in penguins, and they must be considered by conservation biologists.
All species of penguins have color ornaments or black-and-white markings on the head that are pre... more All species of penguins have color ornaments or black-and-white markings on the head that are presented during nuptial displays. This suggests that they are used in mate choice and evolve by sexual selection. Because a high degree of cooperation by both mates is required for successful breeding, mate choice is important. We modified the ornaments of penguins, especially the highly ornamented King penguins, concluding that mutual mate choice occurred but was not equal between the sexes. We found a new signal, ultraviolet (UV) color, in large nonnesting penguins. Their beaks reflect yellow/orange carotenoid pigments and UV from beak spots. A new pigment, Spheniscin, is reflected from ear and breast feather patches. Females preferred males with larger ear patches, so both mutual and female-based selection occurred. The UV signal was dynamic and changed with body condition during fasting and with parasite density. Pigmented ornaments changed color according to the richness of marine resources.
Marine ornithology, Apr 15, 1991
PubMed, 1980
The Mandrill (Mandrillus sphinx) and the Drill (M. leucophaeus) differ by approximately 30% of th... more The Mandrill (Mandrillus sphinx) and the Drill (M. leucophaeus) differ by approximately 30% of their genes as shown by electrophoretic studies. The reasons of this differenciation are discussed with regard to divergence of characters, geographical isolation, and social organization of both species.
The Condor, Feb 1, 1996
The islands of Amsterdam and St. Paul each appear to have been inhabited by endemic populations o... more The islands of Amsterdam and St. Paul each appear to have been inhabited by endemic populations of ducks that were exterminated by humans or human-introduced mammals in the past two hundred years. The duck from St. Paul is known only from a historical account in 1793. Abundant bone remains of a duck from Amsterdam Island are described as a new species, Anas marecula. This was a small, teal-sized species with very reduced wings and pectoral girdle, so that it was certainly flightless. The short, pointed bill suggests a possible derivation of the species from an ancestor related to the widgeons formerly segregated in the genus Mareca.
Polar Biology, Jan 14, 2009
In a past issue of Polar Biology, Meyer-Rochow andShimoyama (2008) conclude their article with “u... more In a past issue of Polar Biology, Meyer-Rochow andShimoyama (2008) conclude their article with “unless evi-dence can be provided in favour of, Wrstly, UV sensitiveretinal receptors in penguins and, secondly, a behaviouralrole for a UV pattern of a penguin, we would regard UVreXectivity in penguins as a biologically unimportant phe-nomenon, associated with optical properties of a structureat a particular stage of growth and development.” Here, weexpress our dissent from this statement and provide furtherevidence strongly suggesting the signi Wcance of UV signalsin intraspeciWc penguin communication.First, Bowmaker and Martin (1985) found that the conetypes of Humboldt penguins
Ibis, Jun 28, 2008
Although studied for 3 5 years, knowledge of the reproductive biology of the King Penguin Aptenod... more Although studied for 3 5 years, knowledge of the reproductive biology of the King Penguin Aptenodytes patagoiziczis remains incomplete. The chick requires more than 12 months of care, which extends the breeding cycle, including moult, to more than one year, i.e. the King Penguin is neither annual nor biennial. In an attempt to resolve ambiguities in the literature and to elucidate the long-term breeding strategy of the species, we studied breeding frequency at the individual level, considering the decision to breed in relation to breeding history over the previous few years. Although adult birds attempted to breed annually (0.83 breeding attempts per year), successful rearing occurred, a t best, every two years only (maximum of 0.41 fledged chick per pair). Comparing successive years, the number of breeding birds in the colony was stable but the number of fledged chicks varied from 29 to 278 over eight years. These results suggest that King Penguins adopt (as individuals) an opportunistic reproductive strategy, in that they usually lay an egg every year, even when failure is certain. Nevertheless, the decision t o breed was not entirely blind, and we identified groups of birds that invested differentially in breeding attempts.
Ethology, Aug 17, 2011
Species in which the sexes equally exhibit colourful ornaments are an issue for evolutionary theo... more Species in which the sexes equally exhibit colourful ornaments are an issue for evolutionary theory. Among several hypotheses, sexual selection for mutual mate choice and social selection for signals of behavioural dominance are most commonly supported. We examined the previously documented sex-similar size of yellow-orange ear patches in the king penguin, Aptenodytes patagonicus. This species is monogamous and pairs just before reproduction. Raising a chick requires considerable effort by both parents, as they alternate care of their single offspring with foraging at sea. The size of the ear patches appears to signal aggressive territoriality in the breeding colony for both sexes. However, experiments suggest that females prefer large patch size during mate choice, and males do not prefer this trait. We tested whether the size of the coloured ear patch was influenced by sexual selection for couples that had recently paired. We used analyses of covariance to compare the size of the ear patch to a measure of body size and then tested for the difference between males and females. Males were 6.2% larger in ear patch width and 7.7% larger in ear patch area than females, and the distance between the ear patches over the head was 7.5% smaller in males, with all differences highly significant. Consequently, sexual selection appears to favour larger ear patches in males, possibly because of an excess of males that promotes female choice. Social selection also appears to favour the evolutionary maintenance of ear patches of males, and thus both types of selection may contribute to enlarged ear patches.
The Auk, Apr 1, 1990
We studied the morphometrics, breeding biology, genetics, and calls of Pachyptila desolata, P. sa... more We studied the morphometrics, breeding biology, genetics, and calls of Pachyptila desolata, P. salvini, P. belcheri, and P. turtur in the southern Indian Ocean. Multivariate analysis of the measurements of live birds revealed some overlap among closely related taxa. Comparisons of biological data provided evidence for ecological segregation between taxa, based mainly on phenology of breeding but also on diet. Calls differed significantly between taxa, and multivariate analysis showed no overlap between syrupattic taxa. These data were then compared with data from other taxa (P. crassirostris and macgillivrayi) and from different localities. We support the recognition at the species level of each of the four study taxa.
Uploads
Papers by pierre Jouventin