Résumé
A good description of a social structure in which individuals live in stable social groups must also capture individual differences in social behaviour in order to understand the selective pressures behind formation and maintenance of those groups. Depending on the evolutionary mechanism acting and the nature of the benefits incurred by individuals, we might expect different patterns of intra-group associations. Female and immature sperm whales (Physeter macrocephalus, Linnaeus 1758) live in stable and partially matrilineal social units. Using photo identification and sloughed skin sampling for genetic determination of sex and relatedness, we investigated patterns of association within a social unit of sperm whales from the eastern Caribbean. Focus was given to how short-term spatio-temporal associations reflect relatedness among unit members. Contrary to previous findings, we found that the patterns of association among members of this unit were heterogeneous and that individuals had preferred associations or avoidances with specific individuals. Furthermore, these preferred associations correlate with relatedness between individuals, such that individuals associated more with their close relatives when variation in sociability of the individuals is controlled. These results are inconsistent with the simple equivalence model of homogeneous associations between members of a social unit. They indicate intra-unit social complexity, a basis for which seems to be genetic relatedness.
| Langue d'origine | English |
|---|---|
| Pages (de-à) | 143-151 |
| Nombre de pages | 9 |
| Journal | Behavioral Ecology and Sociobiology |
| Volume | 63 |
| Numéro de publication | 1 |
| DOI | |
| Statut de publication | Published - nov. 2008 |
Note bibliographique
Funding Information:Acknowledgements Research in Dominica was carried out under a scientific research permit (SCR 013/05-02) provided by the Ministry of Agriculture and Environment of Dominica. We would like to thank all of Balaena’s crew members, Andrew Amour and the staff at the Anchorage Hotel and Dive Center for critical logistical support while in Dominica and Ron Burns at Northwoods DNA for completing much of the genetic lab work. Erica Johnson, Marie Auger-Méthé, Devin Lyons, and two anonymous reviewers each provided helpful comments on this manuscript. We also thank Jens Krause for drawing our attention to the work of Miklós and Podani (2004). This project was supported by operating and equipment grants to H.W. from the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Whale and Dolphin Conservation Society, to Luke Rendell from the UK Natural Environment Research Council, and S.G. was supported during the course of this study by an NSERC Postgraduate Scholarship (PGS-M). To the knowledge of the authors, this research complies with the current laws of the Commonwealth of Dominica.
ASJC Scopus Subject Areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology