Many people in our society have long argued that men and women have inherent traits thanks to our very natures. While some point to patriarchal interpretations of religion to prop up centuries-old myths, others have relied on faulty science to support their misguided assumptions about innate tendencies regarding power, sexual inclinations, and life goals.

Out today, University of Melbourne professor Cordelia Fine‘s Testosterone Rex: Myths of Sex, Science, and Society does the public service of deconstructing the biological and societal tenets on which the continued inequality of the sexes is largely founded.

But, as the professor of history and philosophy of science writes, dismantling gender norms won’t be enough to bring real, sustainable change: “[G]ender constructions are a core part of our developmental system,” and humans are incredibly impressionable when it comes to learning social norms. For this reason, we need to determine what kind of culture we want to live in as we break down the gender binary. If it were up to me, that culture would embody many of the signs on view this past weekend at the Women’s March on Washington.

Using humor and her uniquely accessible academic writing style, Fine starts with the sexist way the concept she calls “Testosterone Rex” was created. The power assigned to testosterone has taken on a life of its own as researchers focused on the assumed differences in the sexes, resulting in cultural norms that have embedded variations of “Men are strong and assertive! Women are meek and passive!” into our culture.

“[W]e often think of biological sex as a fundamental force in development that creates not just two kinds of reproductive systems, but two kinds of people,” she writes in the introduction—with an acknowledgment that there are more than two genders and that sex assignment and gender are not equivalent.

This “two kinds of people” nonsense was confirmed the same way as many other genetic discoveries: through fruit fly research. British biologist and researcher Angus Bateman took Charles Darwin’s observation that “the males of almost all animals [have] stronger passions than the females” and codified it into accepted theory. It turns out, however, that Bateman’s research was poorly done and deliberately shaded to produce his expected result. Fine counters this still-pervasive idea through both common sense and subsequent research, disrupting what we think we know about gender difference.

As I read through her dismantling of Testosterone Rex, I wondered: How do we change our culture’s expectations of people in the public eye when it comes to gender constructions? In an effort to further investigate that question, I reached out to Fine via email. I grounded my questions in this quote from the final section of her book as she contemplates a future without Testosterone Rex:

[W]e’re geared toward learning from those who are prestigious, successful, or similar to us in some important regard, with whom we come to identify, and from whom we learn, internalize, and gain our understanding of cultural norms. Gender constructions penetrate just about every aspect of this cultural legacy … Every newborn human inherits gender constructions as an obligatory part of their developmental system: gender stereotypes, ideology, roles, norms, and hierarchy are passed on via parents, peers, teachers, closing, language, media, role models, organizations, schools, institutions, social inequalities … and, of course, toys.

Here is a lightly edited transcript of our conversation.

Rewire: When reading your first chapter breakdown of the “eggs are expensive while sperm are unlimited and cheap” foundational theory of men as promiscuous cheaters and women as choosey and chaste, I kept hearing Monty Python’s “Every Sperm Is Sacred” satire of gender roles from The Meaning of Life. How did this idea become so pervasive and why was it so important for you to start there?

Cordelia Fine: It’s only fair to say that, at least in part, this became an unquestioned principle not just because intuitively it makes so much sense—as anyone who has given birth to a child will attest, the biological work involved in bringing a new person into life is extremely unevenly split—but this principle does apply to many species. It’s also probably fair to suggest that cultural assumptions about female nature mean that evidence counter to the “chaste female” view failed to make as much of a conceptual dent as it should have. As anthropologists like to quip: “I wouldn’t have seen it if I hadn’t believed it.”

I spent a lot of time thinking about where to start the book. In the end, I thought it was important to begin “at the beginning,” so that readers could consider the other material in the book without the misconception that questioning the “cheap sperm” view of human sexual relations isn’t special pleading for humans to be exempted from foundational principles that apply to every other animals. And to understand that, even within a species, biological sex doesn’t necessarily inscribe a fixed template for how the important business of reproduction should be achieved.

Rewire: You describe the question “How does this sex difference in the brain or hormones make females and males behave, think, or act differently?” as a way to answer “the red herring problem that Testosterone Rex explains.” How did society get so fixated on scientifically backing up the claim that men and women are inherently different, and what should we be asking instead?

CF: When we look around society, we see very striking segregation by sex. It can be tempting to assume that striking effects have a simple, powerful cause: biological sex, sending males and females on a divergent developmental course.

As to the questions we should be asking, it’s really important that feminist critiques not be caricatured as being “anti-science” or against sex being investigated at all. There’s a new, growing body of scholarship discussing how to investigate sex-related variables in a way that recognizes the genetic and hormonal components of biological sex are complex, nonbinary, dynamic, and always entangled in a particular context.

Rewire: The gender dynamic shift is, at least in part, already under way—but it seems to be dramatically one-sided. “Women have stampeded into traditionally masculine roles like law, medicine, accountancy, and management,” you write, but “there hasn’t been a reciprocal rush by men toward traditionally feminine roles, like early education and nursing.” Is this really just because “women’s work” typically comes with a lower salary?

CF: Beyond economics, what is feminine is also often stigmatized for males—that’s why it’s so much easier to be a “tomboy” than a “sissy.”

Rewire: The gendered toy issue is one that every feminist parent I know frustratedly deals with on a regular basis. You quote a journalist advocating for the status quo of pink and blue aisles as saying “a toy business’s job is to make profit, not engage in social engineering.” Your response was one of my favorite parts of the book:

Some thoughtful readers might wonder why the laissez-faire philosophy of gender-neutral marketing is “social engineering,” while toy aisles that dictate which toys are for whom are considered to be leaving things to take their natural course.

Why aren’t we marketing all toys to the broadest possible audiences??

CF: One obvious answer is that you can sell more products when you have “girl” and “boy” versions that can’t be handed down [to a child of another gender]. You can also appeal to kids’ social identities as a girl or a boy, by implicitly or explicitly labeling toys as “for boys” and “for girls.” But also, marketers are people too, embedded in a web of cultural assumptions about what boys and girls are—and should—be like.

Rewire: I found some definite hope in this sentence: “Children see that the category of sex is the primary way that we carve up the social world, and are driven to learn what it means to be male or female.” Does this mean that developing a more healthy view of gender in our culture could naturally lead to more equity in the generations that would follow?

CF: Certainly. And this is exactly what we’ve seen over time, more or less. But, of course, there’s also no magic bullet for changing stereotypes, norms, and expectations.