Student Prize Award Abstract
2000 Poster Paper Honorable Mention

POSTURAL CONGRUENCE IN A CAPTIVE GROUP OF CHIMPANZEES (PAN TROGLODYTES)

S. E. Jazrawi Department of Anthropology, University of Calgary, Calgary, Alberta, Canada T2N 1N4

Postural congruence occurs when two or more individuals adopt similar body postures in the context of social interaction. Similarity in posture is thought to be an indicator of similarity in views or roles in a group, or "rapport" between individuals. Until Boyd's (1998) study of Tonkean macaques (Macaca tonkeana), investigation into the phenomenon had been restricted to human subjects only. The objective of this study was to test whether or not postural congruence occurs in a male-bonded non-human primate species: chimpanzees (Pan troglodytes). Factors including age, sex, rank, posture, and behavior were tested to evaluate hypotheses about the expression and function of posture sharing. Observations of the social and postural behavior of 17 chimpanzees (Pan troglodytes), living in three types of social groups (multi-male, multi-female, uni-male-multi-female) at the Primate Foundation of Arizona, were made over a five month period. 201.25 hours of observation (805, 15-minute samples) were collected. Postural congruence was shown to occur in chimpanzees. Sex, age, and rank influenced the frequency and duration of posture sharing episodes. Differences in the frequency and duration of posture sharing bouts were seen between the three types of social groups. The results of this study were compared to Boyd's (1998) study of Tonkean macaques (Macaca tonkeana) and studies of human posture sharing behavior. Supported by the University of Calgary, and the Province of Alberta Graduate Scholarship.