Across primate species, immature females demonstrate greater interest in infants than males do, likely because practice with infant care increases a mother's chance of keeping her baby alive

Sex Differences in Primate Social Relationships During Development. Joyce F. Benenson. In The Oxford Handbook of Evolutionary Psychology and Behavioral Endocrinology. Edited by Lisa L. M. Welling and Todd K. Shackelford. May 2019. DOI: 10.1093/oxfordhb/9780190649739.013.3

Abstract: The chapter focuses on the social development of immature primates across several species in the Cercopithecidae and Hominidae families, in particular rhesus macaques, the great apes, and humans. The chapter provides an overview of critical factors that characterize the rearing environments of immature females and males, including social structure, residence patterns, and dominance relations. Regardless of rearing environment, consistent sex differences in immatures occur in relationships with mothers, adult males, same-sex peers, and infants. Additionally, sex differences regularly are found in rates of development, quests for dominance, frequency of social play, and rate and intensity of direct aggression across species.

Keywords: Sex differences, primates, social relationships, development, social behavior, dominance, aggression, social play