One phenomena observed in primate groups is that females care for infants that are not their own (allomothering). In this way, infants may receive extra care and get the opportunity to build early bonds to non-mothers. On the other hand, allomothering may be costly for infants if care is not appropriate. To which degree infants are handled by non-mothers depends on maternal permissiveness/restrictiveness.

This study investigates the costs and benefits of mothering and allomothering style on infant development. Behavioural observations focus on interactions between infants and female group members, infant social development as well as motorical and foraging behaviour. In addition, infant physical development is documented through regular photographs taken with a digital camera.