Longitudinal study of dominance relations among captive patas monkeys

Eight and a half years of dominace relations within a captive group of patas monkeys were analyzed. It was found that matrilineal kinship significantly influenced individuals' ranks. In contrast, with the exception of certain intramatiline changes, increasingage had no predictable effect on overall rank, at least for females (this was untestable for males). Offspring typically challenged maternal dominance and in eight or twelve dyads, offspring either fully rose over their mothers (three cases all daughters) or at least achieved dominance ambiguity with them. Additionally, two of the four younger sisters with an opportunity to rise in rank over an older sister did so. The group dominance hierarchy was unstable for 75% of the study due to a combination of agonistically induced and demographically induced rank changes. Concentration of the highest ranks in a single matriline showed a stronger association with group hierarchy stability than did the presence of an adult, nonatal male. Group hierarchy stability was associated with increased affiliation (sitting close and sitting touching), but otherwise there were no behavioral correlations. Individuals' ranks within the group hierarchy were unrelated to their chances of being wounded or having diarrhea. Adult females' ranks were over twice as stable as the group hierarchy (57.1% stability), but stability/instability was not correlated with any behavioral changes. Available evidence suggests tha dominance relations play only a minor role in the organization of patas monkeys' intragroup behavior.