Abstract # 11:

Scheduled for Saturday, September 13, 2014 01:15 PM-01:30 PM: Session 4 (Decatur A) Oral Presentation


V. Wilson1,2, H. Buchanan-Smith2,4, M. Gartner1, A. El-Shaarawi3, R. D'eath3,5, A. Little4 and F. B. Morton2,4
1University of Edinburgh, Department of Psychology, 7 George Square, Edinburgh EH8 9JZ, United Kingdom, 2Scottish Primate Research Group, UK, 3The Royal (Dick) School of Veterinary Studies, University of Edinburgh, UK, 4Behaviour and Evolution Research Group, Psychology, School of Natural Sciences, University of Stirling, UK, 5Scotland’s Rural College, Edinburgh
     In humans, studies suggest that face width indicates dominance and status in males, which has been linked to testosterone. In brown capuchin monkeys (Sapajus apella), we recently found similar links between facial width, alpha status and ratings of Assertiveness. This suggests that facial traits may act as social signals pertaining to an individual’s status. To test this theory, we examined the response of capuchins to faces differing in facial Width-to-Height ratio (fWHR), using two models that represent life-size, unfamiliar, capuchins - one wide-faced and one narrow-faced. Latency to approach was compared with a no-model condition and a real monkey condition (a subordinate and a dominant member of the group). Preliminary results from 10 subjects showed a significantly longer latency to approach the model or monkey condition than the no-model condition, (t(12.35) = -3.58, p = .004). However there was no significant difference in latency to approach a real conspecific versus a model (F(1) = 0.43, p = .52). There was also no significant difference in latency to approach the wide versus narrow faced models, or the dominant versus subordinate conspecifics (F(1) = 0.07, p = .79). We discuss results in the context of both signaling theory, and the use of realistic stimuli in testing primate perception of social signals.