Abstract
When two social groups are close enough to hear each other's short-range vocalizations but not yet close enough to see each other, they can choose whether to approach to initiate a direct contest. In this study, I evaluated whether expected payoffs and group resource-holding potential affected the likelihood of approach toward a neighboring group during naturally occurring intergroup interactions and experimental playback trials by grey-cheeked mangabeys (Lophocebus albigena). Females approached calling groups at low rates, and only if males did so as well. Groups that had recently arrived (≤30 min) at the interaction location were more likely to approach than groups that were in the interaction location for >30 min. Site residency likely indicates the degree of short-term, local resource exploitation, and explains this pattern of patch defense. There was no evidence that mangabeys defended home range core or peripheral areas, that males defended female mates, or that infant defense affected the likelihood of approach. Surprisingly, resource-holding potential had no effect on patterns of contest initiation, but may influence other aspects of intergroup contests. The unexpected importance of payoff asymmetries, relative to asymmetries in resource-holding potential, points to the need for an expanded theoretical framework.
Original language | English (US) |
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Pages (from-to) | 491-508 |
Number of pages | 18 |
Journal | International Journal of Primatology |
Volume | 35 |
Issue number | 2 |
DOIs | |
State | Published - Apr 2014 |
Externally published | Yes |
Bibliographical note
Funding Information:Acknowledgments I thank M. Cords, M. Crofoot, R. Delgado, E. Fernández-Duque, M. Kinnaird, J. Rothman, J. Setchell, and two anonymous reviewers for their insightful comments, and C. Akora, M. Alum, R. Busobozi, A. Happy, P. Kabagambe, S. King, D. Kyalikunda, R. Sunday, and A. Twineomujuni for assistance with data collection. This project was funded by the following organizations: the National Science Foundation (GRFP, Physical Anthropology DDIG #0824512 2008, LEEFS GK-12 Fellowship, and SBE Postdoctoral Fellowship #1103444); the Ford Foundation; the Leakey Foundation; Columbia University; the New York Consortium in Evolutionary Primatology (NSF IGERT #0333415); the International Primatological Society; and an anonymous private donor. The findings and conclusions presented here are my own and do not necessarily reflect the views of the above institutions.
Keywords
- Game theory
- Intergroup interaction
- Lophocebus albigena
- Playback experiment
- Sex differences