Food provisioning of infants in captive social groups of common marmosets (Callithrix jacchus jacchus) and cotton-top tamarins (Saguinus oedipus oedipus)

This study examines the development and dynamics of food provisioning of infants in social groups of two callitrichid species, Callithrix jacchus jacchus or the common marmoset, and Saguinus oedipus oedipus or the cotton-top tamarin. Callitrichids are organized socially in communal breeding systems, in which all group members participate in carrying and sharing food with newborn infants. Intraspecific and interspecific variation in the behavior of parents, older siblings and infants, aged 5 to 16 weeks, was examined using analyses of variance and paired t-tests.

Results showed that the food provisioning process was basically very similar in the two species studied. However, it was proposed that the participation of older siblings in provisioning may influence that of each parent. In addition, marmoset infants ate more independently than tamarin infants of the same age. This could be related to variation between species in ecological and dietary adaptations in the wild.

Food provisioning serves as a method of food learning for infants; it allows them to obtain rare and preferred food items; and it improves inclusive fitness in the group.