“A sexist mythology has been baked into biology, and it distorts the way we perceive female animals. In the natural world female form and role varies wildly to encompass a fascinating spectrum of anatomies and behaviours.”
In the 1940s and ’50s, French embryologist Alfred Jost executed a series of brutal experiments on rabbit fetuses in the womb in order to determine the root of sex differentiation. All mammal fetuses begin with the same parts; he sought to understand exactly what determined their outcome. What he established was that high concentrations of testosterone catapulted the fetus toward male sexual development. Meanwhile, the lack of this hormone was assumed to push the fetus toward what was considered to be the “passive default”: female sexual development. This messed up theory became elevated to a universal truth and dubbed the Organizational Concept.
“Becoming a male is a prolonged, uneasy and risky adventure; it is a kind of struggle against inherent trends toward femaleness,” Jost declared at a conference in 1969. If that statement feels eerily prescient of the kind of jargon peddled by modern misogynists such as Joe Rogan and Andrew Tate, that’s because it is. Part of why Jost’s theory was so widely accepted in the first place was because it fit so neatly with another white male scientist’s already popular views on sex: Charles Darwin’s notion that males were generally dominant and females passive. When we look at science—just as when we look at history—we must always look at who authored it.
In Bitch: On the Female of the Species, zoologist Lucy Cooke disembowels this framework by examining animals that challenge our notions of sex and, more specifically, what is female. For example, we now know that there is no such thing as a “male” or “female” hormone; we all possess a mix of both. In fact, every sex hormone originates as cholesterol; all that differs is the amount of enzymes that convert them and where hormone receptors are distributed. And as Cooke points out, there are many animals that display how messy these distinctions are.
Look no further than the Crocuta crocuta, the spotted hyena. Females of this species have an eight-inch clitoris that is both shaped and positioned exactly like their male counterparts’ penises. Not only that, they get erections and have fused labia that appear just like furry testicles. Females have no vaginal opening; instead, they urinate, copulate, and even give birth through their clitorises. To top it off, female hyenas are larger and more muscular (and they are not the only species; South American bats, blue whales, and more follow this trend). And while it was assumed that this might be because of higher testosterone levels, the truth was more complex.
For female spotted hyenas, the answer lies not in the amount of testosterone but the timing of it. As it turns out, a female hyena’s testosterone levels are only high when she’s pregnant. Another androgen (the group of “male” hormones that includes testosterone) called androstenedione is typically present when mammals are carrying females; produced by the ovaries, it gets turned into estrogen. However, in the spotted hyena’s case, it gets converted to testosterone instead—influencing the developing female’s brain and genitals. This is but one example of how female sexual development is far from passive; it has simply been conveniently overlooked.
And then there is the female mole with gonads and the female spider monkey with a larger phallus than the males. But enough about genitals and hormones—what about chromosomes? Even these have more plasticity than we are taught to believe. Take the common frog, some of which follow the same XY pattern as humans with XX resulting in ovaries and XY in testes; and in others, many sex changes and variations occur due to both environmental and genetic factors, resulting in XY females and XX males. In this species, estrogen can cause sex reversal from male to female, upending Jost’s hypothesis around the all-powerful nature of testosterone.
Nature offers a sprawling diversity of what it means to be female. So, why are human females who challenge cultural notions of our sex—such as trans women like myself—deemed to be unnatural? To say that we are an exception because we are human is to reinforce the idea that humans are separate from nature. And yet, somehow, I’m the one warring with nature—all because I don’t fit neatly into a biological paradigm invented by misogynistic men who wanted to ensure that their sex continued to be perceived as the dominant one. In a binary hierarchy such as this, what could be more dangerous than someone seen as male “choosing” to be female?
As if that weren’t criminal enough, trans women are then charged by others for upholding hyperfemininity—despite this reinforcing the idea that femininity itself is negative (seen as passive and weak). Not to mention, it paints trans women as a monolith, when I know plenty of trans women who prefer not to present as hyperfeminine, even if doing so increases our risk of being harmed. Others accuse us of erasing what it means to be a woman altogether. But I have no interest in dictating how anyone relates to their womanhood, so long as they do the same.
A friend of mine once told me: “Welcoming you as a woman has never once taken away from my understanding of what it means to be a woman—it has only expanded it.” Studying variations of females in the natural world invites us to do the same. We should remain critical and curious when it comes to the organizational concepts our society is structured around and who invented them. I have always found it strange that anyone would take science as static, when nature is constantly expanding and evolving. As Cooke notes, variation is the hallmark of evolution. Like life itself, biology should be dynamic, diverse, and always subject to change.