Abstract # 1023 Event # 112:

Scheduled for Friday, August 19, 2005 10:45 AM-11:00 AM: Session 8 (Mayfair Room) Oral Presentation


FACTORS AFFECTING GROOMING, PROXIMITY, AND AGGRESSION IN SIFAKAS (PROPITHECUS EDWARDSI) IN RANOMAFANA NATIONAL PARK, MADAGASCAR

T. Morelli1, Z. J. Farris2, E. E. Louis3 and P. C. Wright1
1SUNY Stony Brook, Department of Ecology & Evolution, 650 Life Sciences, Stony Brook, NY 11794, USA, 2University of Arkansas, 3Center for Conservation and Research, Henry Doorly Zoo
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     We investigated which factors affect affiliative and agonistic behaviors in sifakas. We predicted that rates of grooming and proximity would be higher between relatives than non-relatives, higher between cohort-mates (individuals born in the same year), and higher between males and females than same-sex dyads. We predicted the opposite pattern for aggression and that females would inflict more aggression on males (P. edwardsi are female-dominant). We recorded behavior on four well-habituated groups (N = 18) for 2,183 animal hours over 128 days, using all-occurrences sampling methods. We determined relatedness from 17 microsatellite loci using CERVUS. Results were analyzed using One-Way ANOVAs (P = 0.05). Length of time spent grooming and in proximity (0-1 m) varied with category (sex/age) and group (P < 0.01). Related individuals were significantly more affiliative than non-relatives, even when excluding mother-offspring pairs. Similarly, aggression rates were significantly lower between sibling and father/offspring dyads than non-relatives. Surprisingly, rates of aggression were higher between mothers and offspring than between different-aged non-relatives (P < 0.01). Furthermore, the highest rates of aggression, as well as the highest rates of affiliation, occurred between cohort mates (P < 0.001). These conflicting patterns revealed a complex relationship between kinship, familiarity, and behavior in sifakas; kinship was not the only factor determining rates of aggression and affiliation. This study was supported by Margot Marsh, NSF-GRF, PCI, and the Henry Doorly Zoo.