Abstract # 54:

Scheduled for Saturday, August 26, 2017 06:00 PM-08:00 PM: (National Ballroom AB) Poster Presentation


G. L. Vale1,2, L. E. Williams1, S. P. Lambeth1, S. J. Schapiro1 and S. F. Brosnan1,2
1The University of Texas MD Anderson Cancer Center, Michale E. Keeling Center for Comparative Medicine and Research, Bastrop, Texas 78602, USA, 2Georgia State University
     The evolutionary roots of economic behavior have received increasing attention in recent years. The use of games developed in experimental economics has allowed multiple primate species’ economic decision making capabilities to be compared by utilizing similar methodologies. In this study we presented a version of the Assurance Game, previously employed with other nonhuman primates, to investigate whether captive squirrel monkeys coordinate responses to find a payoff-dominant Nash equilibrium. Four squirrel monkey pairs (3 female-female, one male-male) were given the option to select a white token, always yielding a single reward, or a black token, yielding four rewards only if both monkeys selected it on any given trial (200 trials conducted per pair, up to 20 trials per session). Overall, squirrel monkeys pairs did not converge on the payoff-dominant strategy in later trials (final 60 trials: x2: ps>0.05; black-black responses ranged from 20-53%). However, one female pair developed a ‘color matching strategy’, selecting the same colored tokens in 73% of their final 60 trials (x2 = 13.07, df = 1, p<0.001). These two females, along with one other female, developed individual preferences for the black token (binomial tests: ps<0.05). We are running additional sessions to determine whether these patterns remain consistent. Overall, squirrel monkeys showed very little behavioral coordination, although one pair developed a matching strategy that was previously documented in chimpanzees.