TY - JOUR
T1 - Patterns of coalition formation by adult female baboons in Amboseli, Kenya
AU - Silk, Joan B.
AU - Alberts, Susan C.
AU - Altmann, Jeanne
N1 - Funding Information:
We thank the Office of the President of Kenya and the Kenya Wildlife Service for permission to work in Amboseli. The staff of Amboseli National Park provided valuable cooperation and assistance. The members of the pastoralist communities of Amboseli and Longido and the Institute for Primate Research in Nairobi provided assistance and local sponsorship. We thank R. S. Mututua, S. N. Sayialel and J. K. Warutere for their expert assistance in data collection, D. Onderdonk for database assistance, and T. Mustra for assistance in manuscript preparation. This project was supported by grants to J.B.S. from the National Geographic Society, the L. S. B. Leakey Foundation, the UCLA Academic Senate and the National Science Foundation (BCS-0003245); and by grants to J.A. by the Chicago Zoological Society and the National Science Foundation (IBN-9985910 and its predecessors). We thank Louise Barrett and several anonymous referees for helpful comments on the manuscript. This research protocol was approved by the Chancellor's Animal Research Committee of the Office of the Protection of Research Subjects at the University of California, Los Angeles (ARC No. 99-075-02). J.B.S. thanks the Wissenschaftskolleg zu Berlin for research support during the preparation of this manuscript.
PY - 2004/3
Y1 - 2004/3
N2 - Coalitionary support in agonistic interactions is generally thought to be costly to the actor and beneficial to the recipient. Explanations for such cooperative interactions usually invoke kin selection, reciprocal altruism or mutualism. We evaluated the role of these factors and individual benefits in shaping the pattern of coalitionary activity among adult female savannah baboons, Papio cynocephalus, in Amboseli, Kenya. There is a broad consensus that, when ecological conditions favour collective defence of resources, selection favours investment in social relationships with those likely to provide coalitionary support. The primary features of social organization in female-bonded groups, including female philopatry, linear dominance hierarchies, acquisition of maternal rank and well-differentiated female relationships, are thought to be functionally linked to the existence of alliances between females. Female savannah baboons display these characteristics, but the frequency and function of their coalitionary aggression is disputed. In our five study groups, 4-6% of all disputes between females led to intervention by third parties. Adult females selectively supported close maternal kin. There was no evidence that females traded grooming for support or reciprocated support with nonkin. High-ranking females participated in coalitionary aggression most frequently, perhaps because they derived more benefits from group membership than other females did or could provide support at lower cost. Females typically supported the higher ranking of two contestants when they intervened in disputes between subordinates, so most coalitions reinforced the existing dominance hierarchy. Results indicate that female baboons participate in coalitionary aggression in a manner strongly influenced by nepotism and individual benefits.
AB - Coalitionary support in agonistic interactions is generally thought to be costly to the actor and beneficial to the recipient. Explanations for such cooperative interactions usually invoke kin selection, reciprocal altruism or mutualism. We evaluated the role of these factors and individual benefits in shaping the pattern of coalitionary activity among adult female savannah baboons, Papio cynocephalus, in Amboseli, Kenya. There is a broad consensus that, when ecological conditions favour collective defence of resources, selection favours investment in social relationships with those likely to provide coalitionary support. The primary features of social organization in female-bonded groups, including female philopatry, linear dominance hierarchies, acquisition of maternal rank and well-differentiated female relationships, are thought to be functionally linked to the existence of alliances between females. Female savannah baboons display these characteristics, but the frequency and function of their coalitionary aggression is disputed. In our five study groups, 4-6% of all disputes between females led to intervention by third parties. Adult females selectively supported close maternal kin. There was no evidence that females traded grooming for support or reciprocated support with nonkin. High-ranking females participated in coalitionary aggression most frequently, perhaps because they derived more benefits from group membership than other females did or could provide support at lower cost. Females typically supported the higher ranking of two contestants when they intervened in disputes between subordinates, so most coalitions reinforced the existing dominance hierarchy. Results indicate that female baboons participate in coalitionary aggression in a manner strongly influenced by nepotism and individual benefits.
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U2 - 10.1016/j.anbehav.2003.07.001
DO - 10.1016/j.anbehav.2003.07.001
M3 - Article
AN - SCOPUS:1542288224
SN - 0003-3472
VL - 67
SP - 573
EP - 582
JO - Animal Behaviour
JF - Animal Behaviour
IS - 3
ER -