Throughout human history immigrants have always been drivers of cultural change, contributing to the diversity and formation of local cultures by transmitting new knowledge and skills. Nevertheless, xenophobic tendencies that prevent beneficial mutual exchange are on the rise. There is evidence that both tendencies, being tolerant as well as being xenophobe toward strangers, are as such deeply rooted in our evolutionary past. In my Ph.D. project, I aim to examine the evolutionary roots of the underlying behavioral adaptions of immigrants and locals to the consequences of migration, by using the highly cultural and socially tolerant Sumatran orangutan (Pongo abelii) as a model species. We will investigate the behavioural strategies locals and immigrants use to cope with the challenges of and at the same time make use of the benefits of migration in two closely located orangutan populations in the Gunung Leuser National Park in Sumatra, Indonesia. The two study populations show differences in their social tolerance and organization but are assumed to stand in regular exchange through dispersing immigrant males and are thus the ideal study system for this project. By combining behavioral and genetic data, this interdisciplinary study represents the most comprehensive approach to address the question whether cultural transmission follows the immigrant male dispersal pattern in Sumatran orangutans. The ultimate goal for this Ph.D. project is to examine how informational and social benefits drawn from tolerant cultural transmission between foreigners (social learning) affect individuals` survival and reproduction success. In that regard, using extant Asian great apes as a model species will shed light on which factors influenced cultural exchange, tolerance, and xenophobia during human evolution.
My study is conducted in collaboration with the nongovernmental organization FKL (“Forum Konservasi Leuser”) and the Evolutionary Genetics Group, Department of Anthropology, University of Zurich, Switzerland (Prof. Michael Krützen & Dr. Caroline Schuppli).