Doctoral Dissertation Research: Social Responsiveness in Female Nonhuman Primates

In social species, there is variation in the extent to which individuals within groups use the position or behaviors of those closest to them to inform their own behavior; this is called social responsiveness. While previous research has demonstrated that variation in social responsiveness among individuals in a group influences ways in which the whole group behaves, this research has been through work in laboratories or using computer simulations. In order to better understand this phenomenon and how it relates to the evolution of social behavior, this doctoral dissertation research project examines these relationships in natural settings. The investigators use new tracking technologies and advance the field of biological anthropology by introducing non-invasive, image-based techniques for tracking nonhuman primate movements and interactions in the wild. Through this project the investigators create opportunities for both masters’ and undergraduate thesis projects and develop new educational modules on collective animal behavior targeted toward middle-school students. Collective behavior researchers have proposed that socially responsive individuals follow cues given by neighbors to make inferences about environmental conditions and resource locations, while unresponsive individuals gather information privately through independent investigation of the environment. Theory predicts that the extent of within-group variation in social responsiveness produces group-level traits, such as cohesion and collective decision-making regimes, which in turn have consequences for individual fitness. This project has three specific objectives: (1) identify the contexts in which wild female savannah baboons are socially responsive; (2) examine if variation in social responsiveness affects collective behavior; and (3) test if group composition affects individual fitness according to its expected effects on collective movement. To achieve these objectives, novel data are collected in the field using 3D stereo videography and GPS-accelerometer collars. Long-term demographic and behavioral data collected over five decades of population monitoring are used to contextualize results. Furthermore, by considering the simultaneous “bottom-up” effects of individual variation on collective behavior and the “top-down” effects of collective behavior on individual fitness in a highly social primate, this project offers novel insight into the adaptive value of social responsiveness and its role in patterning group-level phenomena. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.