The tolerant chimpanzee - Quantifying costs and benefits of sociality in wild female bonobos (Pan paniscus)

点击翻译按钮获取中文摘要

The way individuals socialize is thought to have direct fitness consequences. Accordingly, animals live in cohesive groups only if it conveys net benefits to the individual and individuals form differential social bonds only if strong bonds increase reproductive success. Although this is a hall mark argument in behavioral ecology evidence for large, slow living mammals is accumulating only slowly. The specific aim of the study is to test predictions linking social interactions in food resources to the resulting stress response and energetic consequences. Our approach combines (a) new focal tree observation methods and (b) new field endocrinological methods that yield high temporal resolution of energy balance. With this approach the cumulative adaptive benefit of repeated social interactions can be measured in terms of variation in individual energy balance promoting survival and reproduction. The goal of the study is to evaluate competing hypotheses for the evolution of social traits like social tolerance and socio-sexual behaviors that pygmy chimpanzees or bonobos share with pre-industrial humans but not with common chimpanzees. Thus, this study on the only habituated nonprovisioned community of bonobos in their natural habitat promises to shed light on the evolution of human social behavior.