MODELS OF AFFILIATIVE RELATIONSHIPS AMONG FREE-RANGING RHESUS-MONKEYS(MACACA-MULATTA) .1. CRITERIA FOR KINSHIP

Understanding the relative importance of various hypothesized organizi ng principles of affiliative relationships among female macaques has b een problematic at least partly because researchers have lacked adequa te statistical techniques for teasing apart the roles of maternal kins hip and rank distance, and because criteria for kinship have varied ac ross studies. We examined the extent to which maternal kinship and ran k distance are independently associated with levels of affiliative int eraction among free-ranging adult females rhesus monkeys (Macaca mulat ta) on Cayo Santiago, Puerto Rico. We used a multiple regression exten sion of the Mantel test to evaluate three models, each using different criteria for kinship. In all three models, kinship emerged as a stron g correlate of affiliative interaction. However, the degree to which r ank distance correlated with affiliative interaction varied across mod els. Hence, the choice of criteria for kinship affected the apparent i mportance of rank distance in multi-generational groups. A model using graded rather than discrete criteria of kinship (Le. degrees of relat edness instead of kin vs non-kin) but differentiating only close kin r elationships (r greater than or equal to 0.125) rather than all kin re lationships (r greater than or equal to 0.0005) accounted for the larg est proportion of the total variance. These results support suggestion s that adult female relationships are organized around several levels of kinship through maternal lines, and not simply by crude distinction s of kin vs non-kin. However, when kin are separated from common ances tors by more than a few links, females appear to behave towards relate d individuals much as they do toward non-kin.