@article{e5e5ae4ae5894a65a41e103cdea77577,
title = "Adolescent male chimpanzees (Pan troglodytes) form social bonds with their brothers and others during the transition to adulthood",
abstract = "Social relationships play an important role in animal behavior. Bonds with kin provide indirect fitness benefits, and those with nonkin may furnish direct benefits. Adult male chimpanzees (Pan troglodytes) exhibit social bonds with maternal brothers as well as unrelated adult males, facilitating cooperative behavior, but it is unclear when these bonds develop. Prior studies suggest that social bonds emerge during adolescence. Alternatively, bonds may develop during adulthood when male chimpanzees can gain fitness benefits through alliances used to compete for dominance status. To investigate these possibilities and to determine who formed bonds, we studied the social relationships of adolescent and young adult male chimpanzees (N = 18) at Ngogo in Kibale National Park, Uganda. Adolescent male chimpanzees displayed social bonds with other males, and they did so as often as did young adult males. Adolescent and young adult males frequently joined subgroups with old males. They spent time in proximity to and grooming with old males, although they also did so with their age peers. Controlling for age and age difference, males formed strong association and proximity relationships with their maternal brothers and grooming relationships with their fathers. Grooming bonds between chimpanzee fathers and their adolescent and young adult sons have not been documented before and are unexpected because female chimpanzees mate with multiple males. How fathers recognize their sons and vice versa remains unclear but may be due to familiarity created by relationships earlier in development.",
keywords = "development, kinship, paternal relationships, social relationships",
author = "Sandel, {Aaron A.} and Langergraber, {Kevin E.} and Mitani, {John C.}",
note = "Funding Information: The research was approved by the Uganda Wildlife Authority and the Uganda National Council for Science and Technology and supported by the Makerere University Biological Field Station. Broader impacts of this project included conservation education and capacity building at Kyakagunga Primary School, Kamwenge District, Uganda. A. A. Sandel was supported by The Leakey Foundation, the University of Michigan, the Nacey‐Maggioncalda Foundation, and the National Science Foundation (1540259 and F031543). J. C. Mitani and K. E. Langergraber are currently supported by NIH RO1AG049395. Nathan Chesterman provided assistance and friendship in the field. For additional support in the field, the authors thank David Watts, Sam Angedakin, Alfred Tumusiime, Ambrose Twineomujuni, Godfrey Mbabazi, Lawrence Ndangizi, Rachna Reddy, and the late Jerry Lwanga. For statistical advice, the authors thank the Center for Statistical Consulting and Research at the University of Michigan, especially Kerby Shedden and Josh Errickson from 2015 to 2017. For comments on an earlier version of this manuscript, the authors thank Marina Cords, two anonymous reviewers, and Karen Bales. For helpful advice and feedback during the development of this project, the authors thank Jacinta Beehner, Thore Bergman, Anne Pusey, Brent Pav, Rachna Reddy, Nathan Chesterman, Andy Marshall, Sam Patterson, Bethany Hansen, Ben Finkel, Barb Smuts, Michael Sandel, Kiku Adatto, and additional friends, family, and colleagues of A. A. Sandel. Funding Information: The research was approved by the Uganda Wildlife Authority and the Uganda National Council for Science and Technology and supported by the Makerere University Biological Field Station. Broader impacts of this project included conservation education and capacity building at Kyakagunga Primary School, Kamwenge District, Uganda. A. A. Sandel was supported by The Leakey Foundation, the University of Michigan, the Nacey-Maggioncalda Foundation, and the National Science Foundation (1540259 and F031543). J. C. Mitani and K. E. Langergraber are currently supported by NIH RO1AG049395. Nathan Chesterman provided assistance and friendship in the field. For additional support in the field, the authors thank David Watts, Sam Angedakin, Alfred Tumusiime, Ambrose Twineomujuni, Godfrey Mbabazi, Lawrence Ndangizi, Rachna Reddy, and the late Jerry Lwanga. For statistical advice, the authors thank the Center for Statistical Consulting and Research at the University of Michigan, especially Kerby Shedden and Josh Errickson from 2015 to 2017. For comments on an earlier version of this manuscript, the authors thank Marina Cords, two anonymous reviewers, and Karen Bales. For helpful advice and feedback during the development of this project, the authors thank Jacinta Beehner, Thore Bergman, Anne Pusey, Brent Pav, Rachna Reddy, Nathan Chesterman, Andy Marshall, Sam Patterson, Bethany Hansen, Ben Finkel, Barb Smuts, Michael Sandel, Kiku Adatto, and additional friends, family, and colleagues of A. A. Sandel. Publisher Copyright: {\textcopyright} 2020 Wiley Periodicals, Inc.",
year = "2020",
month = jan,
day = "1",
doi = "10.1002/ajp.23091",
language = "English (US)",
volume = "82",
journal = "American Journal of Primatology",
issn = "0275-2565",
publisher = "John Wiley and Sons Inc.",
number = "1",
}