Abstract # 155:

Scheduled for Sunday, September 20, 2009 06:30 PM-09:00 PM: Session 14 (Mission Bay Ballroom CDE) Poster Presentation


A. A. Sandel, E. L. MacLean and B. Hare
Duke University, Department of Evolutionary Anthropology, Box 90383, Durham, NC 27708, USA

Inhibition, the ability to control prepotent behavioral responses, is a key component of flexible problem solving and has attracted attention from researchers interested in the evolution of cognition. We modified an object retrieval task which has been used to measure inhibitory control in monkeys and humans, and tested the following strepsirrhine species at the Duke Lemur Center: ring-tailed lemurs [Lemur catta, n=6], mongoose lemurs [Eulemur mongoz, n=6], blue-eyed black lemurs [E. macaco flavifrons, n=7], ruffed lemurs [Varecia variegata rubra, n=6] and Coquerel’s sifakas [Propithecus coquereli, n=6]. Overall, lemurs inhibited the response to reach directly towards food inside a transparent cylinder and reached around the cylinder 55% of the time [n=31, SE=0.05]. Lemurs improved within sessions, inhibiting more frequently in the last five compared to the first five trials [ANOVA, F(1,26)=8.84; p<=0.01]. There was no effect of species [ANOVA, F(4,26)=1.11; p=0.37] or species by trial block (first half vs. second half) interaction [ANOVA, F(4,26)=1.46; p=0.24]. These results suggest that lemurs exhibit inhibitory control in object retrieval tasks but to a lesser degree than some haplorhine species. Ongoing research aims to measure whether inhibitory abilities are similar across contexts or if species vary systematically between contexts in a manner that reflects species-specific ecological adaptations.