Callitrichids use these claws to dig into the bark of trees. Marmosets generally have triangular upper molars , and they lack the third molar found in cebids . Otherwise, the skull of callitrichids resembles that of a small cebid or cercopithecid, with a large braincase, short rostrum, and large, forward-directed orbits. Callitrichids are diurnal and live in family groups. The general pattern of association between males and females is monogamy or polyandry, a mating system where one female has more than one mate.
Females produce one to three young annually.
Young are often carried on the parents' backs. In species where twins are produced, the male often carries the young while the mother forages, transferring them back to their mother only long enough for the offspring to nurse. In the saddle-backed tamarin, a species where polyandry occurs, a female associates with two males only temporarily. Like most small primates, members of this family are primarily insectivorous, although small birds, fruits and seeds, and even gum or sap may be eaten at times. L. C. Drickamer, S. H. Vessey, and J. F. Merritt.