The feminist writer Susan Faludi recently described Donald Trump as an avatar doing battle in the American culture wars. “It’s almost as if the political culture conjured this ‘ur-misogynist’ to go up against our first feminist political candidate,” Faludi said.

This backlash, rooted in nostalgia for traditional gender roles and stable identities, is well described by Frank Browning in his new book The Fate of Gender: Nature, Nurture and the Human Future. In the introduction he writes, “nothing seems to stimulate or threaten conventional stability so deeply as the shifting terrain of gender [and] . . . the steady erosion of gender roles.”

The book is timely. In the past few years, the issue of identifying oneself as transgender — an umbrella term for a person whose sense of their gender does not match the one assigned to them at birth — has risen in profile, helped in part by some serious star power, notably Caitlyn Jenner . But this is also because of the internet, which has provided a platform for transgender individuals to connect as well as to campaign. In turn, companies have responded to trans customers and employees. Take, for example, Facebook’s decision to provide subscribers the option to use a free-form field to customise their gender “to help people better express their identities”, adding to the tech giant’s already extensive list of gender identities.

Today, people are seeking more and more to express non-binary identities, to communicate a language of gender fluidity far more complex and nuanced than the term “gender-bending”, which was around when I was a child listening to the flamboyant, make-up loving Boy George. As one interviewee told Browning, “We are ‘trans’ only to the extent that we are becoming more and more in transition to discovering that there are so many more gender possibilities than most people acknowledge.”

Browning, a gentle and sympathetic narrator, tours workplaces, science labs and kindergartens, talking to trans Mormon parents in Utah, Chinese sex sociologists, blending scientific research with personal anecdote. The world he investigates is one in which transgender men and women, gay marriage and female prime ministers and presidential candidates are breaking down the categories of “male” and “female”. Even the terms gay and straight now seem old-fashioned — in one case, he quizzes two girls on what he perceives as a sensitive issue, whether any of their peers have gay parents, and they roll their eyes while their grandmother quietly informs him that his question seems out of touch.

“Where religion and patriarchy once defined men as the people who naturally run business, lead governments, and make war, we have been forced to examine what it means to be a man and to be a woman — and for a growing slice of humanity to refuse to be either.”

Browning, a former NPR science reporter, argues: “the roles, the perceptions, and the performances that signal the meanings of masculine and feminine are everywhere in flux.” In turn, this has provoked fierce hostility. “Backlash and resentment run deeply through middle- and working-class white America, evidenced not least by the surge in misogynist messages that have surfaced across social media.” This is notable in the case of the Gamergate harassment campaign sparked by complaints about sexism in the gaming industry in the US, but also elsewhere, as seen in the case of British classicist Mary Beard and feminist campaigner Caroline Criado-Perez.

These upheavals are difficult not just for traditionalists but also for feminists. As the author points out, “many radical feminists denounce ‘transwomen’ as false women out to use their male education to undermine feminist progress”. While some celebrated Caitlyn Jenner’s glamorous rebirth, others found her portrayal of femininity retrograde.

What makes this book a success is also its downfall, namely that it lacks a strong argument. Indeed, I found it refreshing to read new reporting into myriad moving and intriguing stories instead of a campaigning agenda.

If there is an overarching theme, it is that the nature versus nurture dichotomy is redundant. As Browning says: “Geneticists and brain scientists have shown us that no matter what XX and XY chromosomes may suggest to the outward eye, masculinity and femininity as well as sexual attraction are far more complex biologically than anyone had previously imagined.”

The Fate of Gender: Nature, Nurture and the Human Future, by Frank Browning, Bloomsbury, RRP£20/$28, 320 pages

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