title: Genetic, spatial, and social relationships among adults in a group of howler monkeys (Alouatta palliata) from Barro Colorado Island, Panama.
abstract: Kinship plays an important role in the social behavior of many primate species, including patterns of intra-group affiliation and cooperation. Within social groups, kinship is strongly affected by dispersal patterns, with the degree of relatedness among group-mates expected to decrease as the tendency to disperse increases. In primate species characterized by bisexual dispersal, relatedness among adult group-mates is predicted to be low, with social interactions shaped largely by factors other than kinship. To date, however, few studies have examined the role of kinship in social interactions in bisexually dispersing species. Accordingly, we collected genetic, spatial and behavioral data on all adult members (three males, six females) in a group of free-ranging mantled howler monkeys (Alouatta palliata)--a bisexually dispersing species of atelid primate--from Barro Colorado Island (BCI), Panama. Analyses of microsatellite variation revealed that relatedness was greater among adult males in this group (mean pairwise relatedness = 0.32 for males versus 0.09 for females). Relatedness among individuals, however, was not associated with either spatial proximity or frequency of social interactions. Instead, sex was a better predictor of both of these aspects of social behavior. While relatedness among adults had no discernible effect on the intra-group social interactions documented in this study, we postulate that kinship may facilitate affiliative and cooperative behaviors among male group-mates when interacting competitively with neighboring howler groups over access to food or potential mates.
authors.affiliation: Department of Environmental Science, Policy and Management, University of California, 130 Mulford Hall, Berkeley, CA, 94720-3114, USA. kmilton@berkeley.edu.
authors.forename: Katharine
authors.initials: K
authors.lastname: Milton
authors.affiliation: Department of Anthropology, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Nolin
authors.affiliation: Department of Anthropology, University of Texas, Austin, TX, 78705, USA.
authors.forename: Kelsey
authors.initials: K
authors.lastname: Ellis
authors.affiliation: Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, 35487, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Lozier
authors.affiliation: Department of Bioscience, Aarhus University, Aarhus, Denmark.
authors.forename: Brody
authors.initials: B
authors.lastname: Sandel
authors.affiliation: Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA.
authors.forename: Eileen A
authors.initials: EA
authors.lastname: Lacey
mesh_terms: D000508:Alouatta / Q000235:genetics / Q000502:physiology*; D063147:Animal Distribution; D000818:Animals; D005260:Female; D014644:Genetic Variation; D008297:Male; D018895:Microsatellite Repeats; D010176:Panama; D012919:Social Behavior
keywords: Alouatta palliata; Bisexual dispersal; Genetic relatedness; QAP; Social network analysis; Spatial associations