I have recently retired and am not taking on new students although I am continuing some research projects. I am interested in understanding the evolution of sociality, social structure, and the patterns of competition, cooperation and social bonds in animal species, including humans. Most of my work has focused on social mammals: lions and chimpanzees. For the last twenty five years I have worked almost exclusively on the long term Gombe chimpanzee project. I have gathered the data from this study into an archive, currently housed at Duke, and I oversee the computerization of systematically collected daily data, incorporating this and related material into a relational database. I also advise on the ongoing field study at Gombe. Combined analysis of the long-term data and focused new data collection in the field enables study of a wide variety of questions. Current projects in my research group include studies of female social relationships and female settlement patterns. We also participate in collaborative work with colleagues at a number of other institutions on studies of life history, personality, and health, including studying the natural history of SIVcpz.