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"Evolutionary biology has always been controversial (not among biologists, but the general public). This is largely because Darwin’s theory directly contradicted the supernatural accounts of human origins rooted in religious tradition and replaced them with fully natural ones."
"In the 1990s and 2000s there were repeated attempts by evangelicals to ban evolution in public schools or teach the so-called “controversy” by including Intelligent Design—the belief that life is too complex to have evolved...
... without the aid of some “Intelligent Designer” (i.e. God)—in the biology curriculum alongside evolution. But these attempts failed when scientists demonstrated in court that Intelligent Design was nothing more than Biblical Creationism...
... gussied up in scientific-sounding prose. Since then, however, Creationism and Intelligent Design have lost a tremendous amount of momentum and influence."
"While these right-wing anti-evolution movements withered to irrelevancy, a much more cryptic form of left-wing evolution denialism has been slowly growing."
"Since Darwin, scientists have successfully applied evolutionary principles to understand the behavior of animals, often with regard to sex differences. However, when scientists began applying their knowledge of the evolutionary underpinnings of animal behavior to humans...
..., the advancing universal acid began to threaten beliefs held sacrosanct by the Left. The group that most fervently opposed, and still opposes, evolutionary explanations for behavioral sex differences in humans were/are social justice activists. Evolutionary explanations...
... for human behavior challenge their a priori commitment to “Blank Slate” psychology—the belief that male and female brains in humans start out identical and that all behavior, sex-linked or otherwise, is entirely the result of differences in socialization."
"Blank Slate psychology is universally rejected by experts, as the evidence for innate sex-linked personality differences in humans is overwhelmingly strong. But experts also universally reject biological essentialism, because the environment does play a role."
"In nearly every species tested to date for the presence of personality, we’ve found it, and sex-linked personality differences are frequently the most striking. Sex-linked personality differences are very well documented in our closest primate relatives, too, and the presence...
... of sexual dimorphism (i.e. size differences between males and females) in primates, and mammals generally, dramatically intensifies these differences, especially in traits like aggression, female choosiness, territoriality, grooming behavior, and parental care."
"Given that humans are sexually dimorphic and exhibit many of the typical sex-linked behavioral traits that any objective observer would predict, based on the mammalian trends, the claim that our behavioral differences have arisen purely via socialization is dubious at best."
"Counterintuitively, the social justice stance on human evolution closely resembles that of the Catholic Church, which generally accepts biological evolution for all organisms, yet holds that the human soul had been specially created and thus has no evolutionary precursor."
"Despite there being zero evidence in favor of Blank Slate psychology, and a mountain of evidence to the contrary, this belief has entrenched itself within the walls of many university humanities departments where it is often taught as fact...
... Now, armed with what they perceive to be an indisputable truth questioned only by sexist bigots, they respond with well-practiced outrage to alternative views."
"I’ve been privately contacted by close, like-minded colleagues warning me that my public feuds with social justice activists on social media could be occupational suicide, and that I should disengage and delete my comments immediately."
"Social justice activists attempt to jump the epistemological shark by claiming that the very notion of biological sex, too, is a social construct."
"In support of this view, recent editorials from Scientific American—an ostensibly trustworthy, scientific, and apolitical online magazine—are often referenced. The titles read, “Sex Redefined: The Idea of 2 Sexes Is Overly Simplistic,” and “Visualizing Sex as a Spectrum”."
"Even more recently, the most prestigious scientific journal in the world, Nature, published an editorial claiming that classifying people’s sex “on the basis of anatomy or genetics should be abandoned” and “has no basis in science” and that “the research and medical community...
... now sees sex as more complex than male and female.” In the Nature article, the motive is stated clearly enough: acknowledging the reality of biological sex will “undermine efforts to reduce discrimination against transgender people and those who do not fall into...
... the binary categories of male or female.” But while there is evidence for the fluidity of sex in many organisms, this is simply not the case in humans. We can acknowledge the existence of very rare cases in humans where sex is ambiguous, but this does not negate...
... the reality that sex in humans is functionally binary. These editorials are nothing more than a form of politically motivated, scientific sophistry."
"The formula for each of these articles is straightforward. First, they list a multitude of intersex conditions. Second, they detail the genes, hormones, and complex developmental processes leading to these conditions...
... And, third and finally, they throw their hands up and insist this complexity means scientists have no clue what sex really is."
"What these articles leave out is the fact that the final result of sex development in humans are unambiguously male or female over 99.98% of the time. Thus, the claim that “2 sexes is overly simplistic” is misleading, because...
... intersex conditions correspond to less than 0.02% of all births, and intersex people are not a third sex. Intersex is simply a catch-all category for sex ambiguity and/or a mismatch between sex genotype and phenotype, regardless of its etiology...
... Furthermore, the claim that “sex is a spectrum” is also misleading, as a spectrum implies a continuous distribution, and maybe even an amodal one (one in which no specific outcome is more likely than others)...
... Biological sex in humans, however, is clear-cut over 99.98% of the time. Lastly, the claim that classifying people’s sex based on anatomy and genetics “has no basis in science” has itself no basis in reality...
..., as any method exhibiting a predictive accuracy of over 99.98% would place it among the most precise methods in all the life sciences."
"Pointing out any of the above facts is now considered synonymous with transphobia."
"We need to acknowledge that trans issues and ideology are complex, and concern one of the most marginalized communities in the world. Because of this, we must give these issues the respect they deserve by approaching them with nuance and compassion...
... instead of crudeness and cruelty. But we must not jettison truth in this process. If social justice activists require scientists to reject evolution and the reality of biological sex to be considered good allies, then we can never be good allies."
"Back when evolution was under attack from proponents of Biblical Creation and Intelligent Design, academic scientists were under no pressure to hold back criticism. This is because these anti-evolution movements were almost exclusively a product of right-wing evangelicals...
... who held no power in academia. Now we have a much bigger problem, because evolution denialism is back, but this time it’s coming from left-wing activists who do hold power in academia."
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