Influence of maternal dominance on mother-infant relationship and allomothering in captive stump-tailed macaques (Macaca arctoides)

The present study investigated how the maternal dominance status influences the mother-infant relationship and the interaction of females other than the mother with the group infants in captive stump-tailed macaques (Macaca arctoides). Nine infants were born into the group; observations were made on these infants during their first six months of life using all occurrences sampling. Eleven measures of mother-infant interaction were used for analyses: total time in contact, on nipple contact, off nipple contact, total time off contact, less than 3 feet away (touching distance), more than 3 feet away (beyond touching distance), total contact broken, leaves by mother, leaves by infant, approach by mother, approach by infant. Although the general course of development of the mother-infant relationship was similar in all mother-infant pairs, there were marked differences in regulation of mother-infant contact based on the maternal dominance status. Infants of more dominant females tend to be more secure and have greater freedom of movement within the group. High-ranking stump-tailed macaque mothers carried their offspring less than lower-ranking females. Infants born to dominant female were found to receive significantly more care contact than the infants of sub-ordinate female. The present study strongly indicated that maternal dominance status was a factor that shaped the nature of stump-tailed infants with group members.