Student Prize Award Abstract
1999 Oral Paper Award

FUR RUBBING BEHAVIOR IN FREE-RANGING BLACK HANDED SPIDER MONKEYS (ATELES GEOFFROYI) IN PANAMA

C. J. Campbell Department of Anthropology, 232 Kroeber Hall, University of California, Berkeley, CA 94720

Members of the Barro Colorado Island, Panama, population of black-handed spider monkeys (Ateles geoffroyi) use three species of the Rutaceae family in a behavior that resembles fur rubbing in the white faced capuchin (Cebus capucinus). This behavior has not been reported from other sites where Ateles spp. have been studied. During more than 1200 hours of observation, 28 episodes of this behavior were recorded ad libitum. All age groups performed this behavior in relation to their proportion in the group (X²₍₂₎ = 3.515, p > 0.05), although there was a trend for juveniles and infants to rub less than would be expected. Sample size permitted that the effect of sex could only be examined in adults. The two sexes fur rubbed disproportionately to their numbers in the group, with adult males accounting for significantly more than expected (X²₍₁₎ = 10.00, p < 0.05). Unlike fur rubbing in Cebus capucinus, season did not impact the frequency of the behavior in this study (X²₍₁₎ = 0.018; > 0.05). The behavior reported here differs in many respects from that reported for Cebus capucinus and does not fit the hypothesis that the behavior functions in repelling insects or other antiseptic purposes. It is proposed that fur rubbing in this group of spider monkeys is a modification of a behavior previously recorded in Ateles spp. and may function in scent marking.