The objective of this study is to investigate the role that social bonds play in the lives of female primates. For primate females, close social bonds may represent an effective response to competitive pressures. When ecological conditions favor joint defense of resources, selection is expected to favor the development of strong social bonds with potential allies. Empirical tests of these linkages have produced equivocal results and little is now known about the long-term effects of social bonds on females' lives. This study will produce comprehensive information about the nature of social relationships, coalitionary support, feeding competition, and aggression among adult female baboons in five well-habituated groups in Amboseli National Park, Kenya. Archival data on female relationships and reproductive histories will be used to evaluate whether variation in the quality of female social relationships is consistently linked to variation in longevity or reproductive success. Together, these analyses will provide new evidence about the structure and function of social bonds among nonhuman primate females.
The hominid fossil record suggests that hominids have always lived in groups, and the extent of sexual dimorphism suggests that the earliest hominids lived in groups that contained multiple females. Ecological pressures may have shaped the nature of social relationships among hominid females, particularly their capacity for collective action and their propensity to form close social bonds. The data obtained in this study will help us to construct more richly textured models of the lives and social relationships of early hominids and to develop a better understanding of the selective forces that shaped the human capacity for cooperation, establishing alliances, and friendship.