Primatologist Frans de Waal examines human behaviour in Our Inner Ape. Tim Radford is proud of our closest relatives

The Guardian (UK)

by Frans de Waal
300pp, Granta, £17.99

Apes are not just our kin, they are also capable of human kindness. A bonobo or pygmy chimpanzee at Twycross zoo is famous for gently rescuing a stunned starling, protecting it and helping it fly away. A female gorilla in a Chicago zoo picked up a three-year-old boy who had fallen 18ft into a primate pit: she cradled him, patted him on the back and handed him back to zoo staff. Both animals proved that apes have empathy. That is, they can imagine how others might feel.

Chimpanzees use tools, and they design new ones for new challenges. They can interrogate humans, and make friendly overtures. They evolve group cultures and pass them on through generations of tribal life. They share food, form alliances, play power games and indulge in sex for political and social advantage as well as for promiscuous gratification. They are capable of murder, and infanticide, but also of gratuitous tenderness.

And like humans, they can choose to care or not to care about their neighbours. Recently scientists reported in Nature that chimpanzees would not lift a finger to provide benefits for chimps from an alien group. You can walk round modern Britain and see the same heedlessness of the "others" everywhere. Thirty years ago, under the influence of Konrad Lorenz and Robert Ardrey, animal behaviourists saw something they called "the killer ape". Chimpanzees fought for hierarchical status, and committed murder to maintain dominance and sexual command. But the discovery of the bonobo - Pan paniscus as opposed to Pan troglodytes - has helped to change the picture. Bonobos make love rather than war. They engage in some variant of sexual activity every one and a half hours. Sex is the bonobo way of settling disputes, appeasing authority and offering tribute to rank, and the pay-off is a peaceful matriarchy rather than a competitive society marshalled by a dominant male.

Frans de Waal is one of the alpha males of primate research: he has spent years studying ape society in colonies in Holland and the US, and he knows a lot about behaviour in the wild, too. When he talks of his chimpanzee acquaintances he sometimes uses language that might once have been dismissed as anthropomorphic. But he is not the only scientist to register intimacy across evolution's 7m-year divide. One biologist recently proposed that chimpanzees be reclassified not as Pan but within the genus Homo: making them as human as the neanderthals might have been, or our ancestor Homo erectus.

This compelling book looks at human behaviour reflected in the planet of the apes, and it reminds us that - like our closest relatives - we are what we are because of aeons of evolution, but there is more to it than just a lust for survival and an urge to replicate our genes. "Nature, Mr Allnut, is what we are put in this world to rise above," Katharine Hepburn said to Humphrey Bogart in The African Queen. She spoke for a generation that believed that humans were not just a product of evolution; but there is nothing beastly about nature. If apes have empathy, ingenuity, table manners and mathematical reasoning, then these must have been supplied by time and the circumstances of survival. So uniquely human features, such as morality, monogamy and the nuclear family, may also be consequences not so much of human culture but of the dictates of natural selection.