Grooming, social bonding, and agonistic aiding in rhesus monkeys

An analysis of simultaneous grooming bouts in a captive group of rhesus mon keys (Macaca mulatta) failed to provide evidence of competition to groom hi gh ranking partners. Not only were grooming supplantations rare, but the hi ghest ranking individuals performing grooming did not groom the highest ran king animals receiving grooming. Lower ranking partners, however, did more grooming in nonkin dyads. Grooming partners aided one another in agonistic episodes, but the individual receiving the aid did not groom the individual providing the aid more than vice versa. Kin dyads did aid and groom one an other at greater than expected rates, but the aider did not receive the gre ater proportion of grooming in the dyed. Males participated in more groomin g than expected, but their grooming was not related to aiding either with r egard to one another or female partners. Animals that were targeted in join t aggression, or aided against, received significantly less grooming from t heir opponents. A general social relationship expressed in partner preferen ces, social grooming, and agonistic aiding better explained the observed pa ttern than any model based on the exchange of services for favors in differ ent currencies. (C) 2000 Wiley-Liss, Inc.