Abstract # 71:

Scheduled for Thursday, August 17, 2006 07:00 PM-09:00 PM: Session 8 (Regency West 1/3 ) Poster Presentation

Genetic structure of two populations of ALOUATTA CARAYA in continuous and fragmented habitats

M. M. Kowalewski1,2 and L. I. Oklander2
1Dept. of Anthropology - University of Illinois UC, 109 Davenport Hall - 607 S Mathews Ave, Urbana, IL 61801, USA, 2Estación Biológica de Usos Múltiples, Corrientes-Museo Argentino de Cs. Naturales, Argentina
     Demographic factors such as group size, group density, and male and female dispersal patterns can significantly affect the genetic structure of a primate population. In addition, habitat fragmentation may isolate populations and limit dispersal opportunities. We studied 7 groups of black and gold howlers inhabiting continuous forest (CF) on Isla Brasilera (27º 20' S, 58º 40' W) and 10 groups of black and gold howlers inhabiting a fragmented forest (FF) in Corrientes (27º 30’ S, 58º 41’ W) in northern Argentina. On the island, several groups have overlapping ranges whereas in FF each group was restricted to a forest fragment. We analyzed the genetic variability of these groups using seven polymorphic microsatellites: 3 for A. caraya (AC14, AC17, AC45), and 4 described for Homo sapiens (TGMS1, TGMS2, D5S117, D8S165). Our results indicate that neither population deviated from H-W equilibrium. However, Fst (inbreeding coefficient) values between-groups in the FF were consistent with a recent genetic differentiation between groups (Analysis of Molecular Variance: Fst=0.08805, p=0.000). In contrast Fst values between-groups in the CF showed no differentiation between groups (AMOVA: Fst 0.00771, p>0.05). These results suggest that habitat fragmentation may serve to decrease the ability of howlers to disperse between groups. Isolation can lead to inbreeding depression unless gene flow is restored by developing of biological corridors.