Socioecology of Territorial Behavior in Wild Chimpanzees

The Jane Goodall Institute, Washington DC

Investigators

Abstract

This project examines the social and ecological factors underlying male chimpanzee (Pan troglodytes) territorial behavior. Long-term studies across Africa have revealed that intergroup hostility is widespread among chimpanzees, but that the frequency and intensity of intergroup fighting vary among populations, and within populations over time, for reasons that are not yet fully explained. Recent analyses of long-term data from Gombe National Park, Tanzania have provided intriguing evidence that male territorial behavior can increase food resources for their mates and offspring, leading to faster rates of reproduction. No study has yet looked in detail, though, at whether males focus territorial effort on important food resources, or if instead the observed increases in food availability are simply a byproduct of some other factor, such as attempts to recruit new females. Efforts to answer questions about chimpanzee territorial behavior have been hampered by the focus of most long-term studies on a single social group ("community"). To fully understand factors affecting intergroup relations, at least two neighboring communities need to be studied. This study will use existing long-term data and new observations from two neighboring communities to determine the effects of numerical asymmetries, female reproductive status, and the abundance and distribution of food resources. This study will involve developing a database of territorial behavior from 33 years of long-term records from Dr. Jane Goodall's study, which are stored in the Jane Goodall Institute's Center for Primate Studies at the University of Minnesota, and will also involve the collection of new field data on chimpanzee behavior and the abundance and distribution of food resources. Chimpanzee territorial behavior has inspired many comparisons to primitive human warfare. By advancing our understanding of the social and ecological underpinnings of chimpanzee territorial behavior, this study will contribute to efforts to explain the origin and evolution of human warfare. Demonstration that male chimpanzees actively compete for food resources will add to a growing appreciation for the importance of resource defense by males. Documenting in detail interactions on both sides of a territorial boundary will fill an important gap in efforts to understand the behavior of one of our two closest living relatives. Intergroup violence affects the lives of millions of people around the world every year. By illuminating the roots of intergroup violence in chimpanzees, this project will help with efforts to identify the causes of intergroup violence in humans. The project will contribute to the education of university students and the general public and will also provide information important for chimpanzee conservation at Gombe and other sites. The project will provide employment, education and training in an economically underdeveloped region of Tanzania. Findings from the project will be disseminated in scientific publications and popular media and presented on websites of the Jane Goodall Institute and the Center for Primate Studies.