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OpinionFebruary 10, 20255 min readMen Are More Prepared for Fatherhood Than We ThinkIn many cultures, men are not involved with hands-on childcare. But biology tells us we are perfectly capable of doing soBy James K. Rilling edited by Megha Satyanarayana Cavan Images/Getty ImagesI like to tell my undergraduates that hormones predispose organisms, including people, to shift their energy among different life goals. When we become parents, hormones help redirect energy from mating to parenting. That being said, most male mammals dont get involved in parenting, but there are some important exceptions.For humans, we know that women experience significant hormonal changes during pregnancy and while breastfeeding that help them bond with their infants. But what about men? Across human cultures and throughout history there have been many societies in which men typically have little or no involvement in caring for infants or even children, including, at times, our own. Does this mean that childcare is unnatural for men? Are we not equipped for it?Growing numbers of gay fathers, single fathers and stay-at-home fathers who take on the primary caregiving role tell us otherwise. And new research shows that men experience similar, if less pronounced, hormonal changes as women that may prepare them for fatherhood. I go into detail about this in my book Father Nature: The Science of Paternal Potential. Mens potential for caregiving is an ancient capacity that has evolved by natural selection. We clearly can do this. We just need to tap into it.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.Birds provide us with a lot of good parenting insights: most male birds both feed and protect their young, making them an excellent model for studying the biology of fatherhood. During the breeding season, birds have high levels of testosterone, and they fight with other males to secure territories that will attract female mates. But then, once the eggs have hatched, they switch to parent mode; they stop mating and begin to care for their young. As they do this, testosterone levels drop. Testosterone is keywhen scientists implanted male birds who had become parents with extra testosterone, they started to act like they were in mating mode again, aggressively expanding their territory and spending less time feeding their chicks. This and other evidence suggests that testosterone drives males to invest more energy in mating and less in parenting.Does testosterone do the same thing in people? Well, studies show that testosterone rises in young heterosexual men when they merely talk with young women they arent related to. And we know that men who report more lifetime sexual partners tend to have higher testosterone levels than those reporting fewer partners. Moreover, one study showed that young, single men with higher testosterone levels were more likely to become partnered fathers over the ensuing four years, suggesting that they achieved greater mating success. All of this is consistent with the idea that testosterone promotes mating effort in human males.And just as in male birds, testosterone levels decrease when men become involved fathers. While we dont like the idea of experimenting with new dads by injecting them with extra testosterone to see if their parenting deteriorates, there are some revealing connections between testosterone and parenting. For example, among new fathers, those with lower levels of testosterone tend to pay more attention to their infant, be more responsive to their infant, express more sympathy for infant crying, and get more involved in the day-to-day care of the infant.We dont know yet what causes these changes in testosterone, but they seem to be more pronounced in men who are more engaged parents. Mens hormones could be responding to cues from their infant so that men who spend more time with their infant show larger declines. Or it could be that testosterone decreases occur earlier in the transition to fatherhood, reflecting a mans psychological preparation for parenthood, and predicting his future engagement.If testosterone interferes with some aspects of parental care, the hormone oxytocin seems to do the opposite. We tend to think of oxytocin as a maternal hormone, and for good reason. It is involved in both childbirth and breastfeeding, and it facilitates mother-infant bonding. But there is now emerging evidence that oxytocin is also involved in father-infant bonding. Although the amount of research is limited, some studies find that fathers of young children have higher levels oxytocin than men who are not fathers. Among fathers, men with more oxytocin in their blood tend to physically stimulate their infants more, for example, by playfully poking them, moving them around in space, or bouncing them on their knee.Better evidence for oxytocin effects on paternal behavior comes from experiments where scientists give new fathers extra oxytocin through their nose, so it can reach their brains, and look at how it affects their parenting. Intranasal oxytocin makes fathers more likely to touch their infants, to reciprocate their infants facial expressions and vocalizations, and to engage them in sensitive and challenging play. At the same time, oxytocin also appears to support connecting with their partner. After receiving intranasal oxytocin, men report finding their female partner more attractive, and couples exhibit better verbal and nonverbal communication when discussing difficult topics. In one remarkable, experiment, men treated with oxytocin kept more distance between themselves and an attractive female confederate, but only if the men were partnered. The interpretation offered was that oxytocin is protecting the pair-bond from outside temptations that may lead men astray.Of course, then, oxytocin must act in the brain in order to influence paternal behavior. And as with birds and testosterone, mandarin voles, one of the few mammals in which males help raise their offspring, offer some hints about what might be happening in humans. When male voles become parents, their brain actually changes, as if preparing them for their new role. Brain cells in an ancient part of the brain called the medial preoptic area sprout more oxytocin receptors, increasing their sensitivity to the hormone. This in turn, activates a dopamine center that rewards that dad for caring for his young. We think something similar may be happening in men. Childrens charms reach into our brains and activate this system so that we find them rewarding and want to take care of them.We know that infants who have warm and caring parents do better in the long run. Yet our culture tends to downplay the role of men as caregivers. But science tells us that men are biologically prepared to be parents. So, embrace it. You are a natural.This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.
