The 85th Annual Meeting of the American Association of Physical Anthropologists (2016)


Baboon social neurobiology: Comparing the distributions of oxytocin and arginine vasopressin receptors in hamadryas (Papio hamadryas hamadryas) and anubis (Papio hamadryas anubis) baboon brains

DANIEL J. COPPETO1, JAMES K. RILLING1,2,3, TODD M. PREUSS8, GARY L. WHITE6, ROMAN F. WOLF6, PABLO R. MORALES7, JOSEPH L. WAGNER7 and LARRY J. YOUNG3,4,5.

1Anthropology, Emory University, 2Psychiatry and Behavioral Sciences, Emory University, 3Center for Translational Social Neuroscience, Emory University, 4Psychiatry, Emory University, 5Silvio O. Conte Center for Oxytocin and Social Cognition, Emory University, 6Pathology, University of Oklahoma, 7Colony Management, Mannheimer Foundation, Inc., 8Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center

April 14, 2016 3:30, A 602 Add to calendar

Several forces shape an organism’s social behaviors; influencing decisions to cooperate or compete, to live gregariously or alone, or to approach or withdraw from social interaction. Research has shown that the hormones oxytocin (OXT) and arginine vasopressin (AVP), and in particular the distribution and density of their receptors in the brain, are essential forces that influence the social decisions of animals. Although the roles of OXT and AVP receptors have been well described in mediating pair-bonding, affiliation, territoriality, and group size across a range of vertebrates, their potential role in mediating primate sociality remains unknown.

To investigate how OXT and AVP receptors influence primate sociality, this study compared receptor distributions between baboon subspecies, the hamadryas (Papio hamadryas hamadryas) and anubis (Papio hamadryas anubis) baboons. Although closely related, these baboon subspecies present different social behaviors, with the hamadryas baboon displaying greater degrees of cross-bonding between males and females, while anubis baboons have a more promiscuous mating system. Using receptor autoradiography to visualize the receptor differences between the two subspecies’ brains, this study hypothesized that the hamadryas baboon would display patterns of OXT and AVP receptors similar to that found in pair-bonding species. Conversely, it was predicted that the anubis brain distributions would more closely resemble that of a more promiscuous species.

Receptor autoradiography revealed differences in the density and distribution of OXT and AVP receptors between the two subspecies. These differences are interpreted in light of known relationships between receptor distributions and social behavior across vertebrates.

Funding provided by the National Science Foundation’s Doctoral Dissertation Improvement Grant (Grant #1413395), and from the Silvio O. Conte Center for Oxytocin and Social Cognition