FIRST STEPS IN THE MACAQUE WORLD - DO RHESUS MOTHERS ENCOURAGE THEIR INFANTS INDEPENDENT LOCOMOTION

This study investigated early interactions between 28 rhesus macaque, Macaca mulatta, mothers and their infants living in captive social gro ups to assess whether mothers actively encouraged their infants' indep endent locomotion and if such encouragement could be considered teachi ng. Mothers differed in their tendency to break contact with their inf ants in the first days of infant life, and this tendency increased sig nificantly with previous reproductive experience. Mothers that left th eir infants early in life were also more likely to engage in backward walking and lip-smacking to their infants than mothers that did not le ave their infants early in life. Infants that were left by their mothe rs in their first days of life broke and made contact with their mothe rs for the first time earlier than infants that were not left by their mothers. Interruption of contact with infants early in their life had no apparent immediate benefits to mothers but did have immediate risk s because it increased the probability of infant kidnapping by other g roup members. Mothers whose infants gave a distress vocalization after the first interruption of contact broke contact with them less freque ntly in subsequent days than mothers whose infants did not vocalize. A lthough some of these findings are open to other interpretations, alto gether they strongly suggest that some mothers actively encourage thei r infants' independent locomotion, that maternal encouragement is sens itive to infant competence, and that encouraged infants display some l ocomotor skills earlier in life than they would have without maternal encouragement.