"Testosterone Rex” writes Cordelia Fine, an excellent writer with a sharp sense of humour, “is the myth that squashes hopes of sex equality. Testosterone Rex is the name she gives to “that familiar, plausible, pervasive and powerful story of sex and society”, which holds that inequality of the sexes is natural, not cultural.

There is a widely shared assumption that the effect of testosterone on the male brain chemistry is what makes boys the stereotypical males, and of course its absence, is what makes girls the stereotypical women. The story goes like this: Women are better at “empathizing and communicating”, while men are better at “systematising” which means understanding and building systems – not just computers and machinery, but also abstract systems such as politics and music. Higher testosterone levels make men intrinsically competitive, goal-oriented, and sometimes socially insensitive, while lower testosterone levels provide women with the hard-wired talent for communality, collaboration, intuition and empathy. Testosterone makes men to naturally prefer higher and riskier jobs, make boys and girls prefer to play with different kind of toys. Shouldn’t then we just accept that boys and girls brains have evolved to be different?

Not so, says Cordelia Fine. In the Testosterone Rex she attempts to dismiss the biological differences between the sexes. She delves deep into science and finds that rejecting the testosterone rex view does not require the denial of evolution or differences in the evolution of sex. Fine addresses the flexibility and the dynamism of sex, the plasticity of the brain, and the gender constructions that penetrate just about every aspect and our society and form the core part of our developmental system. These gender constructions is the key to understand the complex interrelations among sex, gender, and society and they provide a potential explanation for how robust sex differences in preferences, such as toy preferences or the colour coding in toys, for example, “develop around the age that children develop a firm understanding of which side of critical social divide of gender they belong.”

Rearranging gender in the human development system it is not easy, writes Fine, it “involves the reconstruction of the social structures, values, norms, expectations, schemas, and beliefs that penetrate our minds, interactions, and institutions”, all that that influence, interact and become entangled with our biology.

If we want a society that geniously values equal opportunity for development, employment, economic scrutiny, safety, respect, regardless of sex, then we need to change our values not science. We need to be a bit more loud and disruptive. And “stop blaming Testosterone Rex, because that kind is dead.”