Reciprocity and trades in wild West African chimpanzees

  • Cristina M. GomesEmail author
  • Christophe Boesch
Original Paper


Why do animals help other individuals and provide benefits to the recipient, sometimes at personal cost? In this study, we aim to determine if some of the helpful behaviors observed in a group of wild chimpanzees (Taï chimpanzee group, Côte d'Ivoire, West Africa) are exchanged among individuals resulting in a net benefit for both participants. We adopted an inclusive view of exchanges by considering that all commodities (i.e., social behaviors as grooming, sex, support, as well as resources, such as meat) can be exchanged. This would result in “market” type social interactions in which debts of one commodity can be met by giving the same or other commodities. We investigated whether both in-kind exchanges and trades of commodities occurred. The Taï chimpanzees reciprocated the amount of grooming they received and were more likely to give support in agonistic conflicts to those who also supported them. In addition, they traded support for meat and meat for sex. Both male and female chimpanzees exchanged many different commodities, which seemed to result in long-term balanced relationships. Our results suggest that wild chimpanzees rely on other group members to obtain many of the important commodities they need.


Reciprocity Trades Chimpanzees Grooming Support Meat sharing Sex 



We thank the “Ministère de l'Environnement et des Eaux et Forêts”, the “Ministère de la Recherche Scientifique”, the O.I.P.R., the director of the Taï National Park, and the “Centre Suisse de Recherche Scientifique” in Abidjan. Special thanks are due to C. Bolé, N. Gouyan, and N. Oulaï for support in collecting behavioral data. We are very grateful to R. Mundry for invaluable help with the statistical analysis and D. Watts, C. Rowney, U. Rowney-Langergraber and two anonymous reviewers for providing input on earlier versions of this manuscript. This project was funded by the Max Planck Society and the Wenner-Gren Foundation.


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© Springer-Verlag 2011

Authors and Affiliations

  1. 1.Max Planck Institute for Evolutionary AnthropologyLeipzigGermany
  2. 2.Institute for Social, Behavioral and Economic ResearchUniversity of CaliforniaSanta BarbaraUSA

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