Creativity and curiosity could be the results of a genetic blip
Anjana Ahuja reports

Art for art's sake

Consider the following scenario. A kangaroo walks into a bar and orders a whisky. "That will be £3," says the bemused barman. "We don't get many kangaroos in here." The kangaroo replies: "At £3 a drink, it's no wonder."

Not one of the world's funniest jokes, but we can see the humour in it. That is because, although the joke combines several bizarre concepts - English-speaking kangaroos that frequent bars looking for a cheap drink - the kangaroo's riposte is appropriate. Even when confronted with situations that could never crop up in real life, our brains are able to deal with them.

Dr Steven Mithen, an archaeologist at Reading University, puts it down to a clever phenomenon called cognitive fluidity. This allows information stored in different parts of the brain to join up with information tucked away in other areas. Our knowledge of kangaroos, language and bars are all filed separately - we only "get" the joke because we can mix and match concepts to believe momentarily in a whisky-swilling marsupial with a nice line in quickfire wit.

Moreover, says Dr Mithen in his ambitious and groundbreaking book The Prehistory of the Mind, cognitive fluidity is the key to much more than humour. As well as hunting and living more intelligently by crafting better tools, there was another, unintended spin-off - we invented culture. Art, religion and science flourished. But how did modern man become so radically different from his ancestors?

"We have to get round a major dilemma," says Dr Mithen, who will deliver a public lecture at the Science Museum in London tomorrow. "Neanderthals had a capacity for language and their brains were the same size as ours. But there is no evidence of creativity or curiosity. Why?" He suggests that the Neanderthal brain could think only in terms of narrow domains, such as foraging or social relations.

It was not until we could blend the information from different domains that we really came into our own - this is where cognitive fluidity comes in. "A hunter that can impose a human mind on an animal can predict how it will behave," he says. "He will have a tremendous competitive advantage. If he can tailor tools for hunting particular animals, he will hunt more effectively. That requires him to mix his knowledge of artefacts, humans and animals."

That ability to mix information emerged from a genetic accident that rewired the brain, Dr Mithen suggests. This accident, though, offered such superiority over our ancestors that it quickly came to dominate human evolution. An unintended spin-off of this greater brain power was a cultural explosion 30,000 to 60,000 years ago.

Dr Mithen notes there is evidence for a "Big Bang" in culture at this time - the first cave paintings were created, people were burying their dead rather than leaving them to rot, and men were designing tools to do specific jobs, such as hunting game. In other words, art, religion and science, in their most basic forms, were emerging.

Dr Mithen wrote the book because he felt that the "hunter-gatherer" concept wheeled out by evolutionary psychologists to explain every aspect of behaviour was failing to uncover the essence of the modern human mind. He is the main proponent of a new strain of research, cognitive archaeology, which uses ancient artefacts to deduce how ancient minds worked. He has set up the country's only course in the subject.

"I think evolutionary psychology works really well, but not for modern humans," says Dr Mithen. "A good theory needs to be able to go the extra step. It doesn't explain why we are so different from our ancestors and other primates. The psychologists seem hung up on sexual selection, but that cannot explain culture. Creationism doesn't explain it either - culture is not something that was plopped in there by God."

Professor Steven Pinker, the American neuropsychologist, has suggested that art is prized for its uselessness. The owner of an expensive Picasso, say, is signalling his desirability to a potential mate he is so well off that, in addition to being able to provide food and shelter, he can afford to hang a priceless but functionally pointless painting on the wall.

Dr Mithen, who has a penchant for Minimalist sculpture, is unconvinced: "I think Pinker is brilliant but to say that people collect paintings for prestige does not explain why people paint them in the first place. And it doesn't explain people's very diverse choice in art." Dr Mithen offers an alternative explanation.

Because of the elaborate cerebral cross-wiring in modern brains, he says, we cannot help fielding an almost infinite assortment of ideas. That is responsible for the limitless creativity we see in art galleries, cinema, literature and scientific endeavour. Religious beliefs are another by-product, as we strive to make sense of the world around us.

However, there are controversial implications of this endless torrent of ideas. Dr Mithen believes that paranormal beliefs are a scourge. "If anything we have become less rational," he says. Neanderthals didn't worship the Moon, for example. It is cognitive fluidity that has allowed us to impose human values and thoughts on objects. As a result, we are now open to ideas for which there is no evidence in the real world, such as parapsychology."

Dr Mithen skates over the biology and chemistry of how cognitive fluidity arose; he is exploring this in his next book. He gently reminds me that he is an archaeologist. However, as he argues compellingly in his book, peering into the distant past can contribute enormously to an understanding of human behaviour.

"People think that archaeologists are people in funny hats who dig in the sun," he says. "It engenders a peculiar view of what we are about. Archaeology is as important as psychology, linguistics and philosophy in thinking about what it is to be human."

The Prehistory of the Mind: A Search for the Origins of Art, Religion and Science, Phoenix, £8.99.