Abstract # 213:

Scheduled for Friday, June 21, 2013 11:45 AM-12:00 PM: Session 26 (San Geronimo Ballroom B) Oral Presentation


A. Yanagi1 and C. M. Berman1,2
1Department of Anthropology, SUNY at Buffalo, Buffalo, NY 14261, USA, 2Graduate Program in Evolution, Ecology and Behavior, SUNY at Buffalo, Buffalo, NY 14260

Although some researchers suggest that rhesus monkeys exhibit several gestural play signals in addition to the play face, it is unclear whether these gestures meet specific criteria to qualify as play signals. We examined seven candidate signals observed exclusively during social play contexts among free-ranging rhesus monkeys on Cayo Santiago. We asked whether (1) candidate signals differed from actual play behavior in form or temporal patterning and (2) they actually predicted play. Data were collected using a mini DV camcorder by ad libitum (54 hours) and focal animal sampling (n=20 subjects, mean ± SD of 17.2 ± 0.6 hours per subject) between October 2006 and August 2007. Two candidate signals showed no resemblance to any play behaviors. Using loglinear and chi-square tests (n=146 cases), we verified that five candidate gestural signals contained elements that lasted longer or increased their conspicuousness over similar play behaviors (p < 0.01). We used modified PC-MC methods to determine whether the candidate signals predicted play (n=189 pairs). Youngsters were likely to initiate play significantly sooner after candidate signals than in their absence (p < 0.01). Thus, these candidate signals appear to meet critical criteria for signals that promote, moderate or facilitate play. The findings open the door to questions about why multiple play signals have evolved. Supported by the NSF (0622357), Leakey Foundation, and Anthropology and EEB at SUNY Buffalo.