Abstract # 125:

Scheduled for Sunday, September 14, 2014 02:45 PM-03:00 PM: Session 20 (Henry Oliver) Oral Presentation


SOCIAL AND GENETIC FACTORS MEDIATING MALE PARTICIPATION IN COLLECTIVE ACTION IN BLACK HOWLER MONKEYS (ALOUATTA PIGRA)

S. Van Belle1, P. A. Garber2, A. Estrada1 and A. Di Fiore3
1Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico, 2Department of Anthropology, University of Illinois, Urbana-Champaign, USA, 3Department of Anthropology, University of Texas, Austin, USA
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     In a 28-month study of five multimale-multifemale groups of black howler monkeys at Palenque National Park, Mexico, we examined social and genetic factors mediating the participation of adult (N=13) and subadult males (N=5) in naturally occurring howling bouts. For each bout, we recorded each male's participation (i.e., howling) at 1-min intervals, and calculated the percentage of time each male participated. Analyses included only bouts (N = 387) for which all males were in view ?80% of the time. Paternity for 19 offspring and kinship among males were determined based on genotype data from 21 microsatellite markers. The mean percentage of time males participated during howling bouts ranged between 8.9 - 100%. GLMM analyses revealed that males participated more when they were adults compared to subadults (F(1,13) = 13.3, P = 0.003), they had sired offspring compared to males without offspring (F(1,12) = 37.5, P < 0.001), and they frequently spent time within 2 m of adult females (F(1,10) = 5.9, P = 0.036). The percentage of time male dyads howled together was not influenced by kinship (F(1,16) = 0.1, P = 0.874) or the percentage of time males spent within 2 m of one another (F(1,16) = 1.1, P = 0.305). These findings suggest that collective action in male black howler monkeys is driven by individual or direct fitness gains rather than inclusive fitness.