THE OLDEST MASTERS OF ALL; THE BROADER PICTURE

ON 18 December 1994, three French cavers were exploring a canyon in southern France when they felt a draught of warm air coming from a pile of stones. They removed the rubble, and uncovered a vast cave that had been sealed off from the outside world for hundreds of centuries. Inside, they found themselves face to face with more than 200 cave paintings of animals that once roamed Europe: rhinos, lions, bears and bison - stunning portraits now verified as the world's oldest known paintings.

Academic circles have been thrown into turmoil by the discovery of what is now known (after one of the cavers who found it) as the Chauvet cave. Most of the rest of the world remains largely oblivious to the excitement. Apart from a few initial snaps in the press, there has been little opportunity for the general public to admire the paintings, the cave itself having been sealed for research purposes. The publication this week of a new book, with 80 colour photographs of the paintings, should change that, and bring to wider attention one of the most astonishing historical finds of our time.

Preliminary research suggests that the 35,000-year-old drawings were partly religious in nature. The cave, in the Ardeche, in south-east France, was never lived in by humans. Rather, it was a pitch-dark hidden network of galleries, some of them 30m high and 70m long; the Stone Age artists would have required burning torches to illuminate it.

The drawings show a level of artistic ability previously unsuspected for the period. Each masterpiece features perspective, shadow - even movement. (In the picture on the right, some of the rhinos have been cut into the rock surface, so that they appear to be charging out from the walls.) But the Chauvet cave was far more than simply the art find of the decade. It may also offer clues to one of the greatest of all scientific mysteries: the evolution of man's creative mind.

Homo sapiens evolved in Africa some 150,000 years ago, and dispersed around the world about 100,000 years ago. However, there is no evidence of art having existed until around 40,000 years ago. Then, over the following 12,000 years, in Australia, Europe and southern Africa, there seems to have been an as yet inexplicable intellectual revolution in which art was produced. Scientists have long been baffled as to how creative thought developed almost simultaneously in three such separate areas of the globe. Clues in the Chauvet cave- footprints, handprints, bones - may, by offering an unprecedentedly clear picture of prehistoric ritual, help to explain how and why humanity in this period suddenly became able to engage in symbolic thought.

There are three main rival explanations. First, there could have been an as yet undetected global environmental event which triggered the rapid simultaneous development of creative thought. Second, it could be that, after spreading out from Africa, the widely dispersed groups of human colonists each progressed culturally at roughly the same speed, despite different environments. Or, most controversially of all, it could be that the human brain continued to evolve - rapidly, in evolutionary terms - after the emergence of Homo sapiens.

If this last theory is correct, the implications for evolutionary and psychological thinking, not to mention humanity's future prospects, might be considerable. The paintings are spectacular - but the cave's real interest is that, in the words of Jean Clottes, senior archaeologist at the site, "Our research will help us to understand what the Stone Age artists were doing in the cave." Let us hope that it does: for the revolution in human thought which the paintings represent was perhaps the most significant intellectual step ever taken by mankind.

! "Chauvet Cave - the Discovery of the World's Oldest Paintings", is published by Thames & Hudson at pounds 28.