Abstract # 114:

Scheduled for Friday, June 22, 2012 02:00 PM-02:15 PM: Session 18 (Camellia ) Oral Presentation


E. M. Finestone1, K. E. Bonnie2, V. M. Vreeman1, S. R. Ross1 and E. V. Lonsdorf1
1Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, 2001 North Clark St, Chicago, IL 60614, USA, 2Beloit College, Department of Psychology
     The foraging activity of chimpanzees is a complex behavior because individuals must balance personal preferences, nutrient requirements and food availability [Sousa and Matsuzawa, 2006] and at the same time navigate social factors. To examine how social factors may influence chimpanzee food selection we presented six zoo-housed chimpanzees (2 male, 4 female) with pair-wise combinations of 4 different food substances (hoisin sauce, ketchup, mustard and peanut butter) in both solitary and social conditions. Social testing was conducted using an on-exhibit artificial termite mound baited with all possible binary combinations of the substances. We recorded food choices in 30-second group scans for twenty minutes following baiting. The same subjects were then presented with the same choices while temporarily separated from their social group. We presented substance pairs on a tray until each subject completed 30 trials for each pair. A repeated measures ANOVA revealed that subjects varied their selections between conditions (F=13.015, df=1, p=0.015) and that substances were selected less variably in the social condition (F=8.285, df=3, p=0.002). Post hoc tests revealed a significant difference in the selection of the lowest value substance, mustard (p=0.01). These results suggest that chimpanzees alter their food selection criteria in a social context and demonstrate the complexity of foraging in group-living animals.