The Personalities and Life Histories of the Gombe Chimpanzees (Visiting Scholar)
Like humans, chimpanzees vary in their social and nonsocial behaviors, as well as in their affect, reaction to environmental events, and how they process information. These differences, often termed personality, are manifestations of genetic, parental, and environmental effects, and, ultimately, evolutionary forces. Considerable research has shown that personality traits are heritable and related to fitness outcomes, such as survival. These findings have led researchers to ask why, despite the strong links between personality and fitness is there remaining heritable variation? Answering this question requires a long-term study of personality and behavior, reproductive success, and survival in a wild population. This project will be the first to do so by linking two unique datasets. One dataset contains over 50 years of behavioral, reproductive, and mortality data on a community of chimpanzees at Gombe National Park. The other dataset contains personality ratings on a reliable, valid, and well-established questionnaire for nearly all (n = 120) of these chimpanzees by field assistants who have extensive experience observing these individuals. After linking these datasets we will test the hypothesis that personality variation in the Gombe chimpanzees is maintained by balancing selection. To do so we will model the associations between personality and behavior, rank, fertility, and survival time. Finally, we will develop a database that future researchers could use to learn more about personality. For example, they could examine whether maternal rearing styles or climate change have influence chimpanzee personality.