Attachment Differences in Male and Female Infant Monkeys

The mother's relation with the male infant was compared with the mother's relation with the female infant in 32 mother-infant pairs of rhesus monkeys. Mothers had more physical contact with female infants and restrained females more frequently than males. Mothers of males withdrew from, played with, and presented to their infants more often than did mothers of females. Males bit their mothers more often than did females. The frequency and form of mother-infant contacts depend on the behavior of the mother and on the age and sex of the infant.