Social factors (e.g. dominance rank and group size) and ecological factors (e.g. habitat quality and anthropogenic activity) are both known to impact the behavior and physiology of nonhuman primates. However, primates are highly flexible and can adjust to different social and ecological contexts. In my research, I explore primate plasticity by studying behavioral and physiological variation in red colobus monkeys and rhesus macaques.
Female red colobus living in previously logged areas of a tropical forest behave very differently (e.g. copulate less frequently, spend more time feeding, and eat a more varied diet) than females in old-growth forest, which allows them to maintain equivalent reproductive function. This ability to adjust to habitat change illustrates how primate species may have dealt with environmental change over time and can be used to inform conservation efforts.
Male rhesus macaques are also flexible, and their behaviors vary depending on social conditions, such as the stability of the dominance hierarchy in their group. Social factors can also impact physiological measures, including hormone concentrations. In rhesus macaques, dominance rank and mating effort are both positively associated with glucocorticoid concentrations (a physiological marker of stress).
Understanding how behavioral and physiological factors influence each other can provide insight into topics of broad interest to anthropologists, such as the evolution of sociality and cooperation. My current work on spider monkeys and woolly monkeys explores those topics by examining potential physiological markers associated with social interactions.