Rilling, J. K., and J. S. Mascaro. 2017. The neurobiology of fatherhood. Current Opinion in Psychology 15:26–32.

Rippon, G. 2019. The Gendered Brain: The New Neuroscience that Shatters the Myth of the Female Brain. New York: Random House.

Robarchek, C. A. 1997. A community of interests: Semai conflict resolution. In Cultural Variation in Conflict Resolution: Alternatives to Violence, ed. D. P. Fry and K. Björkqvist, pp. 51–58. Mahwah, NJ: Erlbaum.

Roberts, W. P., and M. Krause. 2002. Pretending culture: Social and cognitive features of pretense in apes and humans. In Pretending and Imagination in Animals and Children, ed. R. W. Mitchell, pp. 269–79. Cambridge, UK: Cambridge University Press.

Romans, S., et al. 2003. Age of menarche: The role of some psychosocial factors. Psychological Medicine 33:933–39.

Romero, M. T., M. A. Castellanos, and F. B. M. de Waal. 2010. Consolation as possible expression of sympathetic concern among chimpanzees. Proceedings of the National Academy of Sciences USA 107:12110–15.

Rosati, A. G., et al. 2020. Social selectivity in aging wild chimpanzees. Science 370:473–76.

Rose, A. J., and K. D. Rudolph. 2006. A review of sex differences in peer relationship processes: Potential trade-offs for the emotional and behavioral development of girls and boys. Psychological Bulletin 132:98–131.

Roselli, C. E., et al. 2004. The volume of a sexually dimorphic nucleus in the ovine medial preoptic area/anterior hypothalamus varies with sexual partner preference. Endocrinology 145:478–83.

Roseth, C. 2018. Children's peacekeeping and peacemaking. In Peace Ethology: Behavioral Processes and Systems of Peace, ed. P. Verbeek and B. A. Peters, pp.113–32. Hoboken, NJ: Wiley.