A total of 12 brown capuchins (Cebus paella) will participate in the study. Those subjects will be adolescent females between 4 and 6 years of age. All subjects will be born in captivity in the laboratory, and will have minimal contact with humans. To specify, they will be housed in semi-natural indoor and outdoor areas with constant temperature and humanity, regular feeding schedules, enrichment, and water ad libitum. They will neither be food nor water deprived during testing or at any other time. During the testing phase, six subjects will be actors that pair with an unknown partner of brown capuchin (Cebus paella) from another social group. Partners will be matched as closely as possible on the basis of sex and age.