MOTHER-INFANT RELATIONSHIPS IN 3 SPECIES OF MACAQUES (MACACA-MULATTA,MACACA-NEMESTRINA, M-ARCTOIDES) .2. THE SOCIAL-ENVIRONMENT

This study compared social interactions between mothers, infants, and other group members in rhesus, pigtail, and stumptail macaques living in large captive social groups. Mother-infant pairs were focally obser ved in 4 weekly 30-min sessions for the first 12 weeks of infant life. Rhesus and pigtail mothers were remarkably similar in several contact , proximity, and grooming measures, but their scores were lower than t hose of stumptail mothers. The three species did not differ quantitati vely in interest shown in infants by other group members, as measured by infant handling and grooming. Infant handling in stumptail macaques was always gentle and infants were carefully avoided by other group m embers when off their mothers. Infant handling in rhesus and pigtail m acaques also involved harassment and kidnapping. The frequency of infa nt harassment did not differ in rhesus and pigtail macaques but harass ment was more severe in the former than in the latter species. Rhesus mothers reacted aggressively to a higher proportion of infant handling attempts than pigtail and stumptail mothers. These results confirm th e hypotheses that female interest in infants does not differ among mac aque species and that the quality of infant handling is a good predict or of interspecies differences in maternal protectiveness. Mothering s tyle, however, is probably multidimensionally determined, and to fully understand interspecies differences in mother-infant relationships an d their functional significance, we need to understand the mechanisms by which reproductive and ecological variables influence maternal beha vior and infant development in primates.