Chest-rubbing in captive woolly monkeys (Lagothrix lagotricha)

The correlates of chest-rubbing were studied in a captive group of woolly m onkeys (Lagothrix lagotricha) to assess possible functions of territorial m arking, spacing among competing groups or competing males, reproductive com munication, marking to identify familiar environments, self-anointing, and displacement activity. Chest-rubbing was observed only in sexually mature m onkeys and was a predominantly male activity. Females increased chest-rubbi ng when the original adult male died. Chest-rubbing by the first adult male was more common during the two months that he was mating with two females and at times when keepers were likely to be at the exhibit. The results sug gest a reproductive function for chest-rubbing in both males and females. T here is also support for chest-rubbing as a spacing activity.