Are baboon infants Sir Phillip Sydney's offspring?

Data on mother-offspring interactions in chacma baboons (Papio cynocephalus ursinus) were used to test predictions arising from Bateson's (1994) dynam ic assessment model of mammalian weaning conflicts. The results provide pre liminary support for this model. Infants, rather than mothers, controlled t he amount of investment received in the early postnatal period and infants were motivated to begin foraging in the absence of maternal rejection. Furt hermore, seven out of 10 infants did not display any tantrum behaviour duri ng observations throughout the first year of life. Only those infants consi dered to be vulnerable to a seasonal reduction in weaning foods displayed h igh level tantrum behaviour that was accompanied by an increase in the amou nt of investment received from their mothers. Habitat quality is suggested to be critical in determining the success of a transition to independent fo raging both within and between habitats, with mothers being sensitive to th is and responding appropriately to infants who require increased investment . The high intensity tantrum behaviour is necessary to convey unambiguous i nformation to a mother with imperfect knowledge of the offspring's state, a nd to convey the urgency of need, enabling infants to break into maternal s chedules.