I study the evolution of social relationships, social structure, and reproductive strategies in chimpanzees and other mammals. Most of my work takes advantage of the unparalleled long-term study of the chimpanzees of Gombe National Park, Tanzania, which is now in its 62nd year.

I am interested in the predictors and adaptive value of social relationships, using recently-developed network-based methods to analyze long-term data and data collected during my field work. I am also interested in male reproductive tactics and how demography mediates the efficacy of different sexually-selected reproductive behaviors.

Finally, I study social systems using the network structure of groups to investigate the costs and benefits of group living, with a view to making broader comparisons among non-human primate and human groups.