Comparative analysis of sociality in lion tamarins (Leontopithecus rosalia) and marmosets (Callithrix kuhli): Responses to separation from long-term pairmates

The purpose of the present study was to examine responses to a short-term separation from the partner in 2 species of pair-bonding primates: lion tamarins (Leontopithecus rosalia) and marmosets (Callithrix kuhli). Observations were conducted on well-established pairs during a preseparation baseline, a 1-hr separation, and a postseparation reunion. Lion tamarins responded to separation with increased levels of distress, relative to marmosets. Affiliative behavior increased in marmosets upon reunion, whereas affiliative behavior decreased upon reunion in lion tamarins. In marmosets, there were more trials in which sexual interactions were recorded during the postseparation reunion, whereas in lion tamarins, no increases were observed. The results indicate that the mechanisms responsible for the maintenance of social and sexual relationships may differ in these 2 species.