“It’s really amazing how a woman’s body can do that,” my friend Stephanie said, staring at the tiny baby feet that poked out from under the cover. Having never breastfed, she had awe in her voice and had been peppering me with questions about what it felt like and how it all worked.

“Women’s bodies are so functional,” she said, still in awe, before laughing cynically and saying, “Men’s bodies aren’t like that. They are only good for one thing.”

I laughed but then told Stephanie that I had actually just finished reading a new report, Mother Bodies, Father Bodies: How Parenthood Changes us from the Inside Out, co-published by IAV, Center of the American Experiment, and the Institute for Family Studies. The document summarizes research that reveals that, contrary to popular stereotypes, men are hardwired for more than just sex. They are also hardwired for fatherhood.

Contrary to popular stereotypes, men are hardwired for more than just sex.

According to the report, fatherhood changes a man’s brain in ways that equip him to be a better dad. For example, men typically experience a drop in testosterone after becoming fathers, especially if they are living with the mother of their offspring. These lower levels of testosterone are associated with more responsive parenting. And studies of mammalian fathers in two-parenting species have found that experienced fathers demonstrate enhanced boldness, food-finding abilities, and problem-solving.

Changes in mammal fathers’ brains also serve the function of keeping the father focused on taking care of his mate and family. For example, when exposed to the odors of an unfamiliar ovulating female marmoset, marmoset males who were fathers did not experience the testosterone spike that single male marmosets did.

The report also notes that even in relatively egalitarian countries, most moms and dads retain gendered parenting styles. For instance, dads are more likely than moms to engage in rough-and-tumble physical play. They also seem more likely to challenge their children—or as the authors put it, “to help children gain a competitive edge.” By contrast, mothers are more likely than fathers “to use play as a teachable moment, for example, by talking about numbers and colors,” and to “tilt the playing field to their children’s advantage.”

In one Harvard study, when a six-week-old infant was approached by her mother, her eyes closed, her shoulders relaxed, and her heart rate went down. But when the same infant was approached by her father, her eyes widened, she hunched her shoulders, and her heart rate went up. Other studies have found that dads who engage their children in lots of positive play have children who register the highest levels of popularity with their peers. There is also evidence to suggest that moms’ verbal style of interaction with their children is associated with things like the quality of their children’s memory, problem-solving skills, and language skills.

Even in relatively egalitarian countries, most moms and dads retain gendered parenting styles.

As David Blankenhorn points out, both parenting styles are good; it’s the synergy of them that makes them so indispensable. “‘Be careful’ is a very, very fine piece of advice…. And ‘can you climb to the top?’ is a very, very fine challenge. Both are pretty darned important and it’s not like you have to choose which one is correct. Together, they are great!”

Moms and dads don’t always parent in these ways. But given these general differences, scholars recommend that moms and dads embrace each other’s distinctive parenting styles, while recognizing that they are also capable of parenting in similar and important ways.

My friend Stephanie, a single mother of two, agrees with what the report concludes: that cooperative parenting is best.

“I think that the mom would be more the nurturer. And the dad should be the bad cop. I mean, that’s kind of how it was in the old days,” she says before sighing. “I wish my life was like a movie sitcom back then. It’d be so nice.”

Of course, moms and dads both need to nurture and discipline their children; parenting together doesn’t just mean assigning one set of tasks to moms and another set to dads. But what happens when “cooperative parenting” seems out of reach, as it does for many young men and women like Stephanie?

Stephanie experiences acute guilt over this question. She says that everyone is “programmed” to feel like they need both parents. “That’s a must-have. I always wanted my dad around. Like I’d see other people with their dads, and I would want what my friend has.”

And now she feels terrible that her kids don’t have their dads around. When she talks about it, Stephanie pauses for almost a full minute and her lips quiver. She is not usually a sentimental person, but this makes her cry.

“I know exactly how my son feels. And I never wanted my kids to feel like that. It’s just hard. I didn’t need to make the same mistake.”

As a mother of a toddler and an infant, I’m discovering how easy it is to feel guilty as a parent. When I first read through the Mother Bodies, Father Bodies report, I thought back to my pregnancy with my second son and I fretted about what my eating habits had been. Nothing ever sounded good to me during that pregnancy, and I ate more junk food and fewer veggies than I should have. Reading about how on some days as many as 250,000 neurons are created in each minute in the developing baby’s brain, and how a mother’s health during pregnancy affects fetal development made me feel awful. And the worst part was that it was too late—my son had been born, that phase of development was over.

I hate to think about the situation that single moms like Stephanie are in. They know that their children are in a tough spot. And yet they don’t know what they can do about it. You can tell a high school student to not get pregnant, provide education explaining why it’s best to wait until marriage. But for Stephanie and others, the children have already been welcomed into their lives—there’s no turning back now.

That’s why I was glad to see a sidebar in the Mother Bodies, Father Bodies report in which Bill Doherty and Shonda Craft give some guidelines for single mothers to consider in encouraging “male positive” attitudes in their kids. First, they suggest that moms make a conscious effort “whenever possible to speak positively to their children about their fathers.” Second, to do what they can to encourage fathers to maintain a “consistent, authoritative” presence in their children’s lives. And finally, to “identify and involve positive male role models for their children.”

Single moms, like the rest of us, deserve to be educated about what the social sciences tell us about parenthood, even when we know that that information may be difficult to hear. Just like hospitals promote breastfeeding, even when they know that exclusive breastfeeding is not possible for all women, it is important to find ways to publically, yet sensitively, discuss the importance of both fathers and mothers. This can help single moms as they make decisions about shared parenting and future family planning, and give them the information they need to be the best moms they can be to their kids.