Performance correlates of social behavior and organization: Social rank and reversal learning in crab-eating macaques (M. fascicularis)

Seventeen male crab-eating macaques drawn from two captive troops, were tested on a brightness discrimination, reversal learning task. Fourteen of these animals completed ten reversals. It was found that the performance of the three highest ranking animals from each troop, taken together, was poorer than that of the lower ranking animals that were tested. The high ranking animals made more errors before reaching criterion on both initial learning and the reversal problems. Analysis of error patterns revealed that, while the high ranking animals had no more difficulty than the others in withholding their responses to the previously correct stimulus following reversals, they did not adopt the correct strategy as soon as the low ranking animals. The results have been interpreted in terms of a carry-over of a hypothetical factor or factors resulting from pressures created by the ongoing social dynamics involved in establishing and maintaining a given social rank at the time laboratory testing occurred. Supported by USAMRDC Contract No. DADA 17-73-C-3007.