The biology of fatherhood in humans: Evolutionary origins and cross-cultural perspectives

Human fathers have a flexible psychobiological capacity to respond to committed parenting with shifts in hormones such as testosterone, prolactin, and oxytocin. Across non-human species that have evolved costly forms of paternal care, such hormonal shifts often help to mediate trade-offs between mating and parenting effort. These findings hint at evolved neuroendocrine capacities that help facilitate refocused priorities as men make the transition into fatherhood. Today, fathers commonly cooperate with mothers to raise children in societies around the world. However, their involvement and roles are variable, as they likely were evolutionarily. Thus, the nature of fathers’ hormonal shifts and their influences on behavior are shaped by the ecologies, cultural contexts, and family systems in which those fathering roles find expression. Bringing together these perspectives using data from my research in the Philippines, Congo-Brazzaville, and the U.S. along with other cross-cultural data, I will explore how men’s hormonal physiology variably responds to parenthood and relates to men’s family behaviors and bonds.