The goal of my PhD project is to recognize which factors limit the spread of behavioral innovations and ultimately identify cultural units in Bornean and Sumatran orangutans.
Orangutan females are philopatric. They form clear clusters of female relatives and associate more with each other than with non-related females, regardless the similarity in home range overlap. Tolerance of some and avoidance of other individuals shape association patterns among female neighbors and suggest existence of social barriers within population. I am investigating the importance of these social barriers and their effect on the transmission of innovation (e.g. tool use), other learned skills (e.g. feeding and nest building techniques) and behaviors (e.g. diet) within populations. I collect data to create behavioral profiles of individuals from all sex-age classes in order to relate dyadic similarities to patterns in genetic relatedness, social exposure and home range overlap.