layout of cave art. He puts together the idea that, with the emergence of language, early humans would have been able to share the experience of two and possibly three altered states of consciousness: dreams, drug-induced hallucinations, and trance. These, he says, would have convinced early humans that there was a 'spirit world' elsewhere, with caves-leading to a mysterious underworld-as the only practical location for this other world. He thinks that some of the lines and squiggles associated with cave art are what he calls 'entoptic', caused by people actually 'seeing' the structures of their brains (between the retina and the visual cortex) under the influence of drugs.70 No less important, he notes that many paintings and engravings in the caves make use of naturally-occurring forms or features, suggesting, say, a horse's head or a bison. The art, he suggests, was designed to 'release' the forms which were 'imprisoned' in the rock. By the same token, the 'finger flutings', marks made on the soft rock, and the famous hand prints, were a kind of primitive 'laying on of hands', designed again to release the forms locked in the rock.71 He also notes a form of organisation in the caves. Probably, he thinks, the general population would have gathered at the mouth of the cave, the entrance to the underworld, perhaps using forms of symbolic representation that have been lost. Only a select few would have been allowed into the caves proper. In these main chambers Lewis-Williams reports that the resonant ones have more images than the non-resonant ones, so there may have been a 'musical' element, either by tapping stalactites, or by means of primitive 'flutes', remains of which have been found, or drums.72 Finally, the most inaccessible regions of the caves would have been accessed only by the shamans. Some of these areas have been shown to contain high concentrations of CO2, an atmosphere which may, in itself, have produced an altered state of consciousness. Either way, in these confined spaces, shamans would have sought their visions. Some drugs induce a sensation of pricking, or being stabbed, which fits with some of the images found in caves, where figures are covered in short lines. This, combined with the shamans' need for a new persona every so often (as is confirmed today, among 'stone age' tribes), could be the origin of the idea of death and rebirth, and of sacrifice which, as we shall see, looms large in later religious beliefs.73 Lewis-Williams' ideas are tantalising, but still speculative. What we can be certain of, however, is that none of the complex art, and the ancient ceremonies that surrounded the painted caves, could have been accomplished without language. For Merlin Donald the transition to mimetic cognition and communication was the all-important transformation in history, but the arrival of spoken language was hardly less of a breakthrough. It is too soon to say whether the picture given above needs to be changed radically as a result of the discovery of Homo floresiensis , on the Indonesian island of Flores, and announced in October 2004. This new species of Homo , whose closest relative appears to be H. erectus , lived until 13,000 years ago, was barely one metre tall, and had a brain capacity of only 380 cc. Yet it appears to have walked upright, to have produced fairly sophisticated stone tools, may have controlled fire, and its predecessors must have reached Flores by rafting, since there is no evidence that the island was ever attached to the mainland of Asia. The new species' small size is presumably explained by adaptation to an island environment, where there were no large predators. But, on the face of it, H. floresiensis shows that brain size and intelligence may not be as intimately linked in early species of man as previous scholarship had suggested.74 2 The Emergence of Language and the Conquest of Cold To Chapter 2 Notes and References