Alexander Riley looks at a few of those awkward points where actual “scientific” science conficts with the deeply held beliefs of the “I heart SCIENCE!” community:

… human and nature cannot so easily be pried apart. The evidence of the biological reality of the sex difference — not just in gonads and sex cells, but in personality characteristics and behavioral profiles, on average — is overwhelming, and science is daily producing more. Male and female brains are structurally different in ways that map on to the emerging neuroscientific knowledge on how brain structure affects behavior and capabilities. The feminist claim that these differences are wholly a product of socialization becomes more implausible the more we know. In societies where egalitarian gender ideology is arguably most widespread, such as in Northern Europe, there has been no disappearance of traditional sex differences in choices concerning careers. Men are still overrepresented in fields that focus on systems and objects, and women are still the overwhelming majority in fields dedicated to extensive human interaction and social services.

The radical spirit of ’90s feminism represented by [author Judith Butler’s] Gender Trouble did not stop at “deconstructing” gender in the effort to move toward a world in which gender roles are divorced from biological sex. Sex too had to be subjected to such “problematization.” Radicals used the writing of Anne Fausto-Sterling, a biologist who admitted her work was fundamentally shaped by her “1960s street-activist heart,” to suggest that the sex binary was also an oversimplified social construction. Fausto-Sterling insisted there are at least five sexes: males, females, “true hermaphrodites” with one testis and one ovary, male pseudohermaphrodites with testes and “some aspects of female genitalia” but no ovaries, and female pseudohermaphrodites with ovaries and “some aspects of male genitalia” but no testes. Perhaps, she asserted, several of every hundred people might be in one of the three intersex categories, with — the clincher — an “infinitely malleable continuum” between them.

It was quickly pointed out that Fausto-Sterling had been deceptive in her estimate of the frequency of intersexuality. Leonard Sax, in the Journal of Sex Research, noted that she had counted phenomena such as Klinefelter’s Syndrome (biological males with an extra X chromosome), Turner’s Syndrome (biological females with only one X chromosome), and several other conditions typically not recognized as intersex. One of these alone — late-onset congenital adrenal hyperplasia (LOCAH), which involves the overproduction of adrenal androgens — accounts for 90 percent of Fausto-Sterling’s claimed figure of 1.7 percent of the population that is intersex. But LOCAH is not an intersex phenomenon. Many individuals who have it are never diagnosed because the symptoms are so mild, and all who have it are born with typical male or female genitalia that correspond to the male and female genotypes. Nearly all such individuals go through puberty with the typical sexual development for their genotype, as the condition generally does not manifest in women until the early 20s and in men much later. The true estimate of intersex individuals, Sax argued, is roughly 0.018%, about 100 times lower than Fausto-Sterling’s estimate. That is, more than 99.98% of humans are clearly either male or female in terms of biological sex.

But the attack on “standard sex difference science” was undeterred by this decimation of Fausto-Sterling’s case. In Gender Trouble, Butler criticized the work of an MIT group that had just discovered the region on the Y chromosome responsible for sex differentiation, claiming these scientists ultimately had to invoke cultural symbols of patriarchy to legitimate their explanations. In her view, this betrayed the very notion of an objective science of sex difference. We are always trapped in culture, she wrote, which means we are always trapped in patriarchy. A science of sex is impossible. Radical sex/gender ideology attacked science as male knowledge and elevated female knowledge as superior on the basis that women as a class were treated as inferior. Like blacks and other powerless groups, women — at least, women with a feminist outlook — could critically understand the point of view of men and supplement its lacunae with the fuller vision of the female perspective. Marx made similar claims about the superiority of working-class consciousness, though he did not attempt to cast the very notion of science as a tool of oppression.

The MIT group’s finding that what we now know as the SRY gene determines sex is universally accepted science today, and Butler’s ideological criticism has aged poorly in scientifically literate circles. So has her wild overestimation that perhaps one in ten people is outside the normal sex binary.