First Review of A Billion Years of Sex Differences!

"Accessible but authoritative" - Tom Whipple, The Times

May 21, 2026

The first review of A Billion Years of Sex Differences just appeared in The Times!

I probably wouldn’t have chosen the title - “Why men are promiscuous and women are choosy” - but I’m very happy with the review itself.

Below is a brief excerpt. You can read the whole thing here. And if you’d like a copy of the book, you can order it from the Times Bookshop.

Within every nation, men watch more pornography, use more prostitutes, are more interested in one night stands, masturbate more, cry less, are more likely to murder and die in car crashes than women…
When men have absolute power, they get a harem. When women have power — well, let’s just say that Queen Victoria wasn’t noted for her tendency to fill the court with nubile young men.
And if men can’t get a harem? “Men corner the market on what evolutionary biologists call mate-choice failure, with documented cases involving everything from lampposts to trees to vacuum cleaners.”
Of course, it’s not so much the existence of these differences that is so controversial among his academic colleagues. Rather it is the assertion that these differences are in some way innate. Are women really less likely to fornicate with trees? Or has the patriarchy simply repressed their latent arborophilia?
Stewart-Williams’s position is the former…
Where Stewart-Williams is most persuasive is in laying out the areas of uncertainty, acknowledging the importance of nurture, but arguing forcefully that there is a core of irreducible difference that is so obviously down to nature that — well — it takes a very clever social scientist to claim otherwise.
“No one would argue that female and male raccoons act differently because they’re rewarded for behaviour consistent with arbitrary raccoon gender roles,” he writes. So why do we do that with humans? “Why would natural selection wipe the slate clean of these sex differences in our species alone, only for us to then reinvent the same set of sex differences in every society on record?”

You can order a copy of A Billion Years of Sex Differences from the Times Bookshop here.

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