New York Times–bestselling author Lucy Cooke explores and explodes the myth of the male across the animal kingdom.

On a volcano in Rwanda, a hulking silverback gorilla plays with babies, some of which aren’t even his. Until recently scientists had written off the silverback’s babysitting—male primates aren’t supposed to be softies. But there’s mounting evidence of male behavior across the animal kingdom that bucks our expectations. What if there is no right way to be male?

In Bull, bestselling author and zoologist Lucy Cooke teases out scientific reality from cultural bias to reveal the variety and complexity of male experience in animals. We meet “gay” vulture dads, fish that politely queue for dominance, cooperative “cross-dressing” hawks, and alpha chimpanzees who earn their status through peacekeeping. These are anything but the monolithically violent and selfish males our patriarchal prejudice assumes them to be.

As entertaining as it is rigorous, Bull reveals the scientific pitfalls of gender essentialism. At a time when concern about men, boys, and the future of masculinity itself is at a fever pitch, Cooke unpacks the evidence that being male is more than just a lonely reckoning of size and strength. Our fellow animals show the truth is far more interesting—and inclusive.