Speaker:
Stacy Rosenbaum
Graduate Students, Department of Anthropology, University of California, United States
Title: The ontogeny of male social partner preferences in maturing mountain gorillas (Gorilla beringei beringei)
Abstract:
Social relationships between adult male mountain gorillas and the infants in their groups are quite remarkable, characterized by extreme tolerance, grooming, playing, and many hours of male “babysitting." This is true even in the 40% of groups that contain multiple adult males, where paternity certainty is low. Previous work demonstrated that low-cost parenting is the most likely function of these relationships. Here, I will present data demonstrating that preferences for individual male social partners persist across considerable time spans, even after social upheaval. I will then examine the beginnings of such relationships, specifically the role maternal facilitation plays. Mothers increase their time near adult males in the first year after infants are born, and there is some evidence that they narrow their male social circle, spending more time near one preferred male than they do when infants are older. For a subsample of the population, male rank is a much better predictor of females' choice of male social partner than either paternity or mating history. I will discuss the implications these findings have for understanding paternal kin discrimination in this promiscuous species, and the evolution of mountain gorilla social structure.