I am a primate behavioral ecologist and my research examines the influence of dispersal patterns on male sociality and cooperation, male reproductive strategies, and hormonal correlates of male dominance rank and life history status. I have studied a number of different primate species throughout my career, though the bulk of my research focuses on a population of white-faced capuchin monkeys (Cebus capucinus) in Santa Rosa National Park, Costa Rica. The Santa Rosa primate project began in 1983 and is one of the longest running research projects focusing on Neotropical primates. I began my research at the site in 1997 and in 2004 I became project co-director. Via my collaborations with the Santa Rosa research team and a number of experts in the areas of primate genetics and endocrinology, my research makes use of long-term demographic, life history, behavioral, and biological data (including microsatellites, major histocompatibility genes, and hormones). In addition, since beginning my studies in Santa Rosa, I have been intimately involved in the on-going study of the long-term population trends of the capuchin and howler monkeys in the park. Our team has been conducting park-wide censuses of these two primates since 1983, in order to track the effects of forest protection, forest regeneration, and climate change on primate populations.