1Department of Anthropology, University of California, San Diego, 2Department of Anthropology, Yale University
Saturday 2:45-3:00, 200ABC
Female chimpanzee gregariousness and social interactions vary considerably both within and between populations. Direct comparisons across sites are needed to both quantify the differences and test which factors influence the observed variation in behavior. However, this has been difficult due to methodological differences across studies. Here we compare female social behavior in two communities, Kanyawara and Ngogo, in Kibale National Park, Uganda. These two sites, while only 10 km apart, differ markedly in both ecology and demography providing a unique opportunity to study behavioral variation and corresponding influences within one population. Previous research has suggested that Kanyawara females spend the majority of their time alone and rarely interact with other females. In contrast, Ngogo females are reported to be relatively gregarious spending the majority of their time in association with other females. We conducted continuous focal follows of females at both sites using comparable methods. Female grouping patterns and group randomization tests showed that Ngogo females were more gregariousness than Kanyawara females. However, some females at both sites formed strong dyadic bonds with other females. Rates of social interactions at both sites were higher than previously reported in East African populations, but aggression rates at Kanyawara were high, while grooming was extremely rare; whereas at Ngogo, aggressive interactions were rare while grooming among females was relatively common. We discuss our results within the context of the ecological and demographic differences between the two sites. This study also highlights the need for focal follows of females to understand female behavior.
This reaerch was funded by grants from the LSB Leakey Foundation and Yale University to M. Wakefield and grants from the LSB Leakey Foundation and the University of California San Diego to K. Wild.