The BSA is using neuroscience to justify gender-separated troops. But 'science doesn't support it'

When the Boy Scouts of America allowed girls to join its signature Scouts BSA program in 2019, it did so with a condition: That troops would be separated along gender lines.

This new system of “linked troops” meant that boy units and girl units could exist side by side, and even do some program and camping activities together. But it ultimately kept the day-to-day mechanics of each troop—namely meetings, rank advancement and leadership roles—segregated by gender.

A few years in, this remains a big point of contention. I recently spoke to Kaleen Deatherage, a volunteer who leads Scouts BSA’s diversity, equity and inclusion task force, about this topic. She told me that, when she talks to large groups of scouters in webinars, for example, this issue comes up a lot. “Some units really wish that those troops were fully coed, and it was patrols for boys and girls [together]. And others feel really passionately that it's important for them to be separate.”

When confronted with this tension, Deatherage told me she defers to the science, explaining that “there's lots of adolescent brain development research that supports that boys and girls are neurologically—we kind of develop at about the same pace until somewhere around age eight or nine, and then the girls have a sizable advantage until we're about high school age, then the boys catch back up, and we're off to the races as adults.”

Indeed, one of the BSA’s reasons for this separation is to ensure equal opportunities for each gender, in the face of this imbalance in brain development that apparently gives girls a sizable advantage during the early teenage years. Girls would naturally dominate in a coed troop environment, the argument goes, and crowd boys out of leadership opportunities.

A slide deck developed by one BSA council, about the “opportunity and risk of serving the whole family,” noted that, “we don’t want to short change 11-14 year old boys. They need time and space to mature.”

This understanding of neuroscience has been taken for granted, and reinforced as a response to scouters in the field who advocate for coed troops. But it didn’t fully satisfy my curiosity. For one thing, Scouting units are fully coed in plenty of other countries, including the United Kingdom, Brazil and Italy, just to name a few. Plus, Scouts BSA’s gender segregation creates ongoing challenges for trans and nonbinary scouts navigating a system that was not built to accommodate them.

After I spoke to Deatherage, I did some of my own searching and found that the idea of gendered brain development wasn’t so straightforward. One Nature article in particular intrigued me; it argued that this gendered lens on brain development is a form of “neurosexism” that is based on weak evidence, and that developmental differences between boys and girls can be explained by the cultures in which they are raised, not by biology.

When I brought this up to Deatherage, she told me: “That entire question around what is intrinsic to us, and what is learned behavior so baked into our cultures that it seems intrinsic, feels like a field where so much more study is warranted. I'm not qualified to opine on how to interpret all of [the] research, but I do think Scouting should be diligent in following the research and the data and going where it takes us.”

I decided to dig a little deeper to see where the research would take me. I reached out to Gina Rippon, a professor emeritus of cognitive neuroimaging at Aston University in the U.K. She’s also the author of “The Gendered Brain,” a book that was featured in the aforementioned Nature article.

“Any claim which starts with, ‘boys are-, girls are-, men are-, women are-’ just stops me in my tracks … because it gives the impression that there's two completely non-overlapping groups,” Rippon told me. “Anybody saying that science shows, ‘boys are-, girls are-, etc.,’ is not telling the full story, because in any of these areas, there's a huge variability within each group, anyway, and a huge amount of overlap between the groups.”

The type of scientific studies that the BSA seems to rely on here focus on “tiny average differences which emerge at the population level,” Rippon said, and ignore the comparatively massive areas of commonality.

For example, one study I found concluded “that brain networks develop differently in males and females at puberty, with boys showing an increase in connectivity in certain brain areas, and girls showing a decrease in connectivity as puberty progresses.”

In another article, Frances Jensen, a neuroscientist at the University of Pennsylvania, put it this way: “In adolescence, on average girls are more developed by about two to three years in terms of the peak of their synapses and in their connectivity processes. Of course, some boys mature early and some girls are slow to do so.”

This idea also recently surfaced in The Atlantic, in an article that argued boys should start school a year later than girls to compensate for this gap in brain development and maturity.

Rippon explained that these studies and articles, however, often form the basis of misconceptions:

“If you track the development of brain size in adolescent brains, in a large number of adolescent brains, on average girl brains reach adult size—their eventual size—somewhat earlier than boys. That is a clearer statement,” Rippon said. “If you're saying that every single girl has a brain—every single 10-year-old girl—has brains the same size as a 14-year-old boy, it's absolutely meaningless. So if that's the basis of [the BSA’s] decision, then science doesn't support it.”

She went on to explain that brain size, on its own, also doesn’t have a clear significance.

“If you correct for brain size in any of the comparisons of human brain structures which have been published in the last 50 years, since normal real time brain imaging arrived, there are no differences,” Rippon said.

So it seems pretty clear: Sex differences alone are not to blame for brain development differences. I asked Rippon, then, about the “nature vs. nurture” argument: Even if it’s not based in biology, could it be that cultural forces render teenage girls more capable than boys, therefore justifying their separation in Scouts BSA troops?

She explained that culture does, in fact, have a big impact on brain development.

“Babies arrive in this world as kind of finely-tuned systems picking up clues as to what they're supposed to do, what they're not supposed to do, what they're rewarded for doing, what they're not rewarded for doing,” Rippon said. “Six- and seven-year-old girls and boys are already hugely the product of very powerful social pressures to be a certain way, dress a certain way, play a certain way.”

But if that’s going to be the reason for troop separation in the BSA, Rippon said, “they can't do it on the basis that this is some kind of biologically determined difference. … All they're doing is perpetuating what the world has already done to these individuals.”

She questioned whether that aligns with the goals of the Scouts BSA program.

“I'm obviously not denying that there are anatomical differences between girls and boys, nor am I denying that there are differences between brains. It's just what the relevance is to what these organizations are hoping to achieve,” Rippon said.

She pointed to sports as a type of activity where this type of separation might be more relevant. But even there, she said, the separation need not be based on gender alone. Take boxing, for example, where categories are divided into weight classes.

“If you feel it's necessary to grade people, then you should [ask], ‘Why are you grading them?’ And don't let whether they’re being males or females be the first, the only question you ask,” Rippon said.

Rippon is not alone in her understanding of the science. Lise Eliot, a professor of neuroscience at Rosalind Franklin University, also wrote a book on the topic, and shared her views in The New York Times, in an argument against single-sex education.

“Neuropsychological research has identified very few innate differences between males and females and for most academic and interpersonal skills, the sexes actually overlap much more than they differ,” she wrote. “If we really want women and men to compete on even playing fields, they have to be raised and educated in a truly gender-integrated way, where no one is excluded and both sexes learn how to respect, collaborate with and lead each other through shared experience.”

You’re probably wondering, at this point, what the BSA has to say about all of this. I was, too. I tried, for more than a month, to get answers.

I tried reaching Ellie Morrison, who served as national commissioner of the BSA from 2018-2020, and who I understood to be a key player in the development of the linked troop system. I never heard back.

I also sought a response through Scott Armstrong, the BSA’s director of national media relations. After repeated requests, Armstrong did not connect me to Morrison, and did not respond when I presented him with some of the specific critiques made in this article.

That leaves me feeling pretty skeptical of the BSA’s justification for gender-separated troops. And if there are valid reasons for the separation, it’s clear that at the very least, neuroscience is not one of them.