Integration of new males into four social groups of tufted capuchins (Cebus apella)

We examined how aggressive, affiliative, and sexual behavior function to in tegrate male capuchins (Cebus apella) into a new social group. Nine males w ere exchanged among four social groups. We performed instantaneous scans an d all-occurrence sampling during baseline, introduction, and follow-up peri ods. The study included three different introduction situations: 1) males f amiliar to one another were introduced to a group with no other adult male, 2) males unfamiliar to one another were introduced to a group with no othe r adult male, and 3) males familiar to one another were introduced to a gro up with an existing elderly, resident male. Severe aggression occurred in s ituations 2 and 3, but the introductions were peaceful in situation 1. In a ll cases preceptive females were among the first individuals to affiliate w ith the males, and males did Mot appear to compete for access to preceptive females Following their period of proceptivity, the females that had cycle d remained preferred social partners for the males immature animals also qu ickly affiliated with the new males, and the males tolerated the attention from immatures. Affiliative relationships between the males and nonprocepti ve females developed slowly, and while male-female aggression was mild, agg ression among adult males (familiar and unfamiliar) had the potential to be severe.