Social Aspects of Fur-rubbing in Cebus capucinus and C. apella

Abstract

Capuchins rub particular plant materials into their pelage, a behavior for which most authors have proposed a medicinal function (Baker in American Journal of Primatology 38:263–270, 1996, Baker, M. (1998). Fur Rubbing as Evidence for Medicinal Plant Use by Capuchin Monkeys (Cebus capucinus): Ecological, Social, and Cognitive Aspects of the Behavior. Dissertation thesis. University of California Riverside; DeJoseph et al. in Journal of the American Academy of Dermatology 46:924–925, 2002). Individuals fur-rub solitarily or in groups, but researchers have not conducted studies to understand the differences. We investigated the link between the form of fur-rubbing and other social variables in 2 capuchin species. We supplied 2 captive groups —white-faced capuchins and tufted capuchins— with citrus fruit and onions and explored the behavioral processes and social aspects underlying the activity. We documented the occurrence, number of participants, and effect of recruitment behaviors in fur-rubbing subgroups. We investigated the role of kinship, affiliation, and dominance relationships in accounting for fur-rubbing groups. There is a significant difference in the form of fur-rubbing between white-faced and tufted capuchins. White-faced capuchins fur-rubbed mainly in subgroups and performed a particular behavior to recruit prospective participants, whereas tufted capuchins fur-rubbed mainly alone, and showed no particular motivation to be joined by other group members. White-faced capuchins could fur-rub together frequently, whatever their degree of kinship, affiliation, or dominance interval. In tufted capuchins, fur-rubbing appeared to be significantly affected by kinship and dominance.