13 research outputs found
Appareillage au Quai Branly
Le gros temps des polémiques désormais derrière lui, le Musée du Quai Branly embarque le public aux premiers jours de l’été vers les horizons lointains. En attendant les alizés, son capitaine nous a ouvert ses soutes et guidés pour une visite à la salle des machines..
Fonds concernant l’Asie du Sud des bibliothèques partenaires de la Bulac
Les fonds indiens sont répartis dans trois bibliothèques (CEIAS, Biulo, EFEO) ainsi que dans deux collections plus confidentielles : le fonds Vaudeville et le fonds Jules Bloch. Les trois bibliothèques ont la même définition de l’Asie du Sud : l’Union indienne, le Pakistan, le Bangladesh, le Népal et le Sri Lanka ainsi que le Bhoutan et les Maldives
The social organisation of starling roosts revealed by song dialects
International audienceDialects may signal social or population identity and increase tolerance within communities.We hypothesized that in European starling Sturnus vulgaris communal roosts, birds comingfrom the same breeding area, i.e. dialectal zone, might tend to stay together within the roost.Recordings were performed in the colonies, revealed in earlier studies, multiple dialects andsmall sectors where birds shared the same variants at the different levels. We also performedrecordings in different locations within night roosts. The dialects recorded in the roosts werethe same as those recorded at nest sites during the day and they were not distributed randomlywithin roosts: birds from the same geographical diurnal origin would gather and stay together,either because they arrived together or were attracted to their dialect. Although our resultshave to be confirmed by the study of identifiable individuals, we propose original lines ofthought on roost structuring and on the role of song dialects
Mécanismes comportementaux des invasions biologiques : flexibilité et communication chez l'étourneau sansonnet
National audienc
Mécanismes comportementaux des invasions biologiques (flexibilité et facilitation sociale chez l'étourneau sansonnet, sturnus vulgaris)
On parle d invasion biologique lorsqu une espèce accroît son aire de répartition et qu elle occupe des habitats non colonisés auparavant. Chez les espèces sociales comme l Etourneau, ce processus implique que les animaux puissent quitter leur population d'origine, puis par la suite former de nouveaux groupes sociaux et des populations pérennes. Ce même processus implique que les individus puissent abaisser leur émotivité face aux environnements physiques et sociaux nouveaux. Nous avons émis l hypothèse d après laquelle les individus de populations plus récemment installées dans leur habitat seraient les plus réceptifs à des stimuli sociaux apportant des informations sur celui-ci. Nous avons testé cette hypothèse sur le terrain en comparant la réponse d individus de populations dans des étapes de colonisation différentes à des leurres empaillés et à la repasses d un chorus. Nous avons également testé en laboratoire si les individus de ces mêmes populations présentaient des différences d émotivité face à l isolement social, à des environnements, des aliments et des objets nouveaux. Il en ressort que les individus des fronts de propagation ou des villes réagissent d avantage aux stimuli sociaux puis que dans l ensemble des populations testées il existe une proportion d individus peu émotifs face à la nouveauté. La dispersion dans des habitats nouveaux, l approche d objets inconnus et l intégration de nouveaux items au régime alimentaire apparaît comme pouvant être la combinaison d innovations par les individus les moins néophobes, puis la facilitation sociale et/ou l habituation des autres. Ces mécanismes semblent agir comme facilitateurs des invasions chez cette espèce.Biological invasions occur when a species colonizes new habitats not occupied before, thus when it increases its geographic distribution. In social species like European starling this process requires individuals being able to leave their original population and to form new social groups and perennial populations in the novel habitats. Individuals should also be able to reduce their emotional levels when confronted to social and physical novel environments. We hypothesized that individuals from populations more recently settled in an area would be more attracted by social informative stimuli. We tested this hypothesis with decoys and chorus playbacks on the field and compared the behavioural response of individuals from populations with different colonization histories. We also tested in laboratory their emotional reactions when confronted with social isolation, novel environments and unfamiliar objects and food. Dispersal in new habitats, approaching unfamiliar objects and tasting new food seem to be the result of the combination of innovations by the less neophobic individuals and social facilitation or habituation in more emotive ones. These mechanisms may facilitate invasions in this species.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF
Mécanismes comportementaux des invasions biologiques : flexibilité et communication chez l’étourneau sansonnet
National audienc
Flexibility in European starlings' use of social information: experiments with decoys in different populations
International audienceIndividuals confronted with novel environments, for instance recently modified environments such as towns or recently occupied habitats such as colonization fronts, have to cope with a lack of information about the location of resources. We hypothesized that, under these conditions, individuals of a social species such as European starlings, Sturnus vulgaris, would be more responsive to social cues indicating food presence than individuals belonging to populations already established in a well-known habitat. To test this hypothesis, we displayed starling decoys with various age, group size and interindividual distance characteristics in feeding postures to evaluate their attractiveness to starlings from towns and colonization fronts and noted whether attracted individuals joined particular decoy groups. Our results supported our hypothesis that sensitivity to social cues varied according to the population's history, and we suggest that these cues enhance the success of starlings in occupying new habitats. (C) 2010 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved
The importance of social cues in propagation fronts and other new environments
International audienceIndividuals confronted with novel environments, for instance recently modified environments as towns or recently occupied habitats as colonization fronts, have to cope with a lack of information concerning localization of resources and suitable breeding sites safe from predators. We hypothesized that, under these conditions, a social species like Sturnus vulgaris would be more responsive to social cues indicating food and conspecifics’ presence than individuals belonging to populations established longer in a habitat that they know well. Decoys in feeding postures and a playback displaying a starling chorus allowed us to evaluate their attractiveness level for starlings from towns and propagation fronts. We observed that both kinds of stimuli had more effect on populations in contexts of novelty and that the modalities of response varied qualitatively among populations and depending on the kind of stimulus (visual or acoustic). Our data supported the hypothesis that sensibility to social cues varied according to populations’ history, individuals’ age, and the characteristics of the decoys we used (morphological aspect, group size and interindividual distances). We suggest that these social cues enhance the success of starlings to occupy new habitats