Tyrannosaurus Rex dinosaur model. PA/Rui Vieira. All Rights Reserved.

Cordelia Fine's 2010 best-seller, Delusions of Gender, explored the science and popular thinking behind sex differences and the idea that gender is an innate and immovable force. In her new book, Testosterone Rex, Fine turns to the influence of testosterone and its impact on psychology and inequality between men and women.

It is a rare text: accessible to the non-academic reader while exhibiting rigorous research, drawing on science from evolutionary biology to behavioural studies. It’s an invigorating read that forces you to interrogate your own ideas about gender and testosterone. I found it repeatedly challenging my own assumptions.

“Delusions of Gender actually ended up as a very different book to the one I set out to write,” Fine told me. “I’d been reading a lot of popular books about sex differences in the brain while looking at the scientific studies these authors were citing as hard evidence for those differences. Initially I wanted to write a book that cleared up what science was actually telling us.”

But, she explained: “I discovered real contradictions within the studies... It was confusing, and that confusion led to me writing a book that explored the problems in the science.”

WW Norton & Co (2017)“

To me, Testosterone Rex is the natural sequel,” Fine continued, describing how she “wanted to look at the evolutionary backdrop to the story...at the relations between circulating testosterone and gendered behaviour.” The question: can this help explain enduring inequalities, where men are more likely than women to occupy positions of power and influence?

For example, Fine explores the concept of risk-taking—often considered a “male” characteristic, connected to the idea that risk is reproductively advantageous for males. (That story goes: male ancestors, taking extra risks foraging for food and fighting rivals, found more mates and had more babies as a result).

Fine says these popular narratives draw on “this vintage version of sexual selection to claim an evolutionary imperative for male risk-taking. The next obvious step is to argue that this is a major contributor to persistent sex inequalities, helping to explain why fame, fortune and corner offices are disproportionately acquired by men.”

But, she cautions, things may not be how they seem.

Risk: to whom?

For example, in some species there are reproductive advantages for females in competitive and risky behaviour. Fine adds: our conception of risk itself often ignores the diverse contexts in which individuals live. And as risk-taking is intimately linked to masculinity in our minds, we may fail to notice risks associated with women’s lives.

She explains: “although women routinely take risks, these often seem to slip under the research radar...Going on a date can end in sexual assault. Leaving a marriage is financially, socially and emotionally risky.”

In her book Fine gives other examples, including the risk of “misogynist backlash by writing a feminist opinion piece,” or sex-based discrimination or harassment in the workplace, that might not even be considered by researchers studying risk.

She told me: “I think there’s a general phenomenon that we think of risk and then we think male.” As a result, she warns: when people think about what counts as taking a risk, they tend to overlook examples that are gender-neutral, or more typical for women.

What can be done to challenge this? Fine says she and colleagues are exploring how the association of risk with male lives may “create a form of unintended confirmation bias in research.”

She said: “We’ve been looking at what happens when you modify a commonly used risk-taking survey that looks at health, social, financial, and physical risk-taking, to include items that are more gender neutral or even more feminine. We’ve found this makes a difference.”

In both of her recent books, Fine challenges gender stereotypes and the idea that gendered ways of being are innate. In Delusions of Gender she examined the belief that a “female brain” made women more empathetic. In Testosterone Rex she does the same to the idea, for example, of promiscuity being hard-wired into men as a result of the hormone.

Sticky stories

Why do stories that men are like Y, and women are like X, remain so sticky? Fine says: “The idea that gender differences were critical for achieving reproductive success has a strong intuitive plausibility... [and] if we think that a particular kind of behaviour was important in our ancestral past, we assume that it must be deeply biologically rooted.”

“One of the things I do in Testosterone Rex is to take a closer look at this idea that biology must always be playing the leading role in creating adaptive masculine and feminine behaviours.”

As part of this, Fine reviews a range of research into the behaviour of animals, from crickets to clownfish to hedge sparrows. She gives a thought-provoking example: “One thing we can all agree on is that having sex with the same species is important for reproductive success...And yet, a study on baby goats being fostered by ewes, and baby lambs being fostered by nanny goats, found that the fostered male offspring would grow up with a strong sexual attraction to the foster mother species, rather than their own.”

She said: “That’s an unintuitive phenomenon, but is an example of an understanding in evolutionary biology that offspring don’t just inherit genes, but an entire ‘developmental system.’”

I also asked Fine how our notions of masculinity impact realities of inequality and violence. She said: “There was an interesting study showing that when you present male sexual violence as rising out of an evolved adaptation as opposed to power dynamics, young men perceived perpetrators as having less control, and being less morally responsible for their actions.”

This is why Testosterone Rex is an important book. It consolidates data and evidence to interrogate the narrative that men have evolved to be more competitive, more risk-taking, and more status-seeking. In doing so, it helps us think about the kind of society we expect to see or hope to build. It questions whether we have to accept existing gendered norms about male and female behaviour.

Not only is that exciting, but it offers hope. As Fine put it to me, at the end of our talk: “The research I put forward in Testosterone Rex gives a sense of confidence that we can do better. Of course there’s nothing easy about creating cultural change but the campaign for greater gender equality isn’t us 'going against nature.'”