%0 Journal Article %A Van Leeuwen, Edwin J. C. %A Cronin, Katherine A. %A Haun, Daniel Benjamin Moritz %+ Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, Max Planck Society %T Population-specific social dynamics in chimpanzees : %G eng %U https://hdl.handle.net/21.11116/0000-0002-85E3-7 %R 10.1073/pnas.1722614115 %7 2018-11-05 %D 2018 %* Review method: peer-reviewed %X Understanding intraspecific variation in sociality is essential for characterizing the flexibility and evolution of social systems, yet its study in nonhuman animals is rare. Here, we investigated whether chimpanzees exhibit population-level differences in sociality that cannot be easily explained by differences in genetics or ecology. We compared social proximity and grooming tendencies across four semiwild populations of chimpanzees living in the same ecological environment over three consecutive years, using both linear mixed models and social network analysis. Results indicated temporally stable, population-level differences in dyadic-level sociality. Moreover, group cohesion measures capturing network characteristics beyond dyadic interactions (clustering, modularity, and social differentiation) showed population-level differences consistent with the dyadic indices. Subsequently, we explored whether the observed intraspecific variation in sociality could be attributed to cultural processes by ruling out alternative sources of variation including the influences of ecology, genetics, and differences in population demographics. We conclude that substantial variation in social behavior exists across neighboring populations of chimpanzees and that this variation is in part shaped by cultural processes. %K chimpanzees; animal culture; sociality; behavioral diversity; social learning %J Proceedings of the National Academy of Sciences of the United States of America %O PNAS %V 115 %N 45 %& 11393 %P 11393 - 11400 %I National Academy of Sciences %C Washington, D.C. %@ 0027-8424