Steve Connor: We are living on the planet of the apes

There is something in the swagger and that inane look of intense concentration which is especially noticeable midway through a sentence. Then, with all the publicity for the remake of Planet of the Apes, I realised what was bugging me about George W Bush. It was his simian side, the one that kept telling me that the most powerful man in the world was really a chimpanzee in a suit.

It's not just me that's noticed his ape-like mannerisms. There is, after all, an entire website dedicated to photographic comparisons between the former Texan oilman and our closest living relative (www.bushorchimp. com). But even this inventive webmaster was forced to concede defeat with one particularly stupid-looking picture of Dubya in mid flow. "I apologise for this late entry. I cannot find a chimp making a face as dumb as this one," the webmaster writes in the box where the ape should be.

But, to be fair to President Bush, there is a little simian in all of us. As the geneticists are fond of pointing out, chimps and humans share something like 98.4 per cent of their DNA. We also shared a common ancestor a mere seven million years ago, a blink of the eye in evolutionary time. It is no wonder that we see a bit of them in us, and a lot of us in them, which explains why the remake of Planet of the Apes is fuelling such interest.

To some scientists, Homo sapiens is the "third chimpanzee", meaning we sit alongside the two other species – the common chimp and the bonobo, or pygmy chimp – on anatomically equal terms. The only thing that really separates us is our vast brain, which in Dubya's case is perhaps not as vast as Mother Nature had originally intended.

So although some of us possess a natural ability to ape our simian alter egos, none of us can claim to be above comparison. In fact the more we understand about the chimpanzee's behaviour in the wild, the easier it is to see just how human their societies can look. We now know, thanks to research published in 1999, that wild chimps living in the African forests engage in all sorts of activities that are learnt from one another, from fishing for termites with sticks to cracking nuts with stones. The scientists had no doubt that the 39 learnt behaviours they documented formed a complex simian "culture", an attribute once considered to be unique to humans.

Chimps have more in common with people than we realise. They can recognise themselves in a mirror, they form complex social interactions, they form alliances, they are duplicitous and sneaky and yet at the same time show a degree of conflict resolution that would do credit to any diplomat.

The author William Boyd based his novel Brazzaville Beach on the comparison between humans and chimps. Based on real research, Boyd built up a picture of chimpanzee societies that were not so different from the human ones engaged in studying them. An especially frightening realisation was that bands of male chimps engage in what can only be described as guerrilla warfare on neighbouring chimps.

Apeing one another happens at almost every level. The primatologist Frans de Waal, in his latest book, The Ape and the Sushi Master, tells the intriguing tale of a young chimp deliberately brought up as just another member of a human family. The experiment was brought to a swift end when the mother discovered that her own baby had started to ape the chimp's mannerisms in a frighteningly bestial way.

The point is, we find apes both intriguing and at the same time unnerving precisely because they are so similar and yet clearly different. We share a common heritage that emerges in unexpected ways. As Dubya's facial contortions show, you can take the man out of the monkey, but you can't always take the monkey out of the man.

s.connor@independent.co.uk