I’m no fan of Christina Hoff Sommers and the “Choosey Moms Choose Choice” angle on feminism she’s been pushing for a few decades now, but once in a while I’ve gotta give credit. Earlier in the week, she revisited the gender wage gap, posting the 10 most and least remunerative college majors, along with the gender breakdown for each. Not surprisingly, women still aren’t entering science, technology, engineering or math (STEM) majors at the same rates as men.

This unfortunate aspect of 21st century America always confounds me. Women now earn 58% of college degrees, a statistic that’s touted with glee by “you-go-girl” women’s lifestyle bloggers and advocates of higher education credentialing alike. Yet women are still overwhelmingly choosing some of the lowest-paying professions.

What’s going on here? A few possibilities that come to mind:

Women really are terrible at math/science. Women are fine in math, but aren’t socialized to be interested in STEM. STEM teachers and employers are sexist/hostile toward women STEM workplaces are unresponsive to women’s needs (no pregnancy leave, nursing breaks, etc.) Women dislike being in classes (or professions) with all/mostly men.

Explanation 1 is controversial, and the data seems largely dependent on the personal politics of the Internet Opinion Writer covering it (although some research suggests gender discrepancies in other countries are either nonexistent or reversed).

Explanations 3 and 4 might hold water. Scientist and SciAm blogger Kate Clancy has documented the accounts from female STEM grad students about the hostile (and often lecherous) behavior they’ve encountered from male teachers and colleagues. And evidence suggests that academic scientists (male and female) are biased against female applicants in their hiring practices. It’s unclear whether these same biases exist against female students at the undergrad level, but it’s not so far-fetched to imagine a 60-year-old engineering professor whose thinking has been colored by old-school conventional wisdom like “women are ’emotional’ nurturers, men are ‘rational’ thinkers,” (or whatever) scaring potential undergrad ladies away.

Family-unfriendly workplaces may also play a role. A woman with a PhD in her late-20s/early-30s seeking tenure, who also wants to have children, is likely hurting her ability to publish and research every time she takes a semester-long maternity leave. On the other hand, the magical sorting hat of freshman year is more at play for women undergrads here. I can’t speak for all women, but I sure as heck wasn’t thinking about structural barriers to employment for women when I was 18 and filling out my first class schedule – I just wanted to avoid having any classes before 11 AM.

Explanations 2 and 5 are also compelling. Angelina Jolie in Hackers, or Lex “This is a Unix System!” Wunderkind in Jurassic Park were role models for girls in the 90s who wanted to attain “l33t haxx0r $killz,” and seem to have paved the way for the Quirky Programmer Chick role to proliferate (see: NCIS, Criminal Minds, 24). Yet women remain largely absent from computer science programs.

Even if the socialization of girls and boys into distinct gender roles has less of an impact on their choices than is commonly assumed, there’s still the status quo to contend with, wherein the average STEM course in the average school is going to be filled with mostly men.

There’s a famous model that shows how initially diverse neighborhoods with residents who have no strong racist tendencies, only a slight preference to not be the only member of their race in a community, will over time self-segregate into isolated, racially-homogeneous islands (H/T). Applying the same reasoning to the male-female split in academe, we can understand how women who have above-average aptitude in math and science and a slight preference against being the only girl in class might gravitate away from the male-dominated hard sciences.

As hopeless as that scenario sounds, women have already kicked in the doors of the medicine and life sciences departments (even if that pesky pay gap persists), and international female students are increasingly interested in math-focused sciences, as well.

There’s likely a combination of factors that impacts 18-20-year-old women’s interest in going into math and science. We might look to the recent increase in women libertarians as an indicator of what’s possible for women in STEM majors. In many ways, science is a lot like the liberty movement: It focuses a lot on philosophical abstractions, rational/logical economic reasoning, it’s historically been dominated by men, and – let’s be real – it’s also historically been full of nerds. And yet, more young women keep signing up anyway.

There is hope, friends, for both STEM and for liberty!