Читать книгу The Rational Optimist: How Prosperity Evolves - Matt Ridley, Matt Ridley - Страница 20

Then there appeared upon the earth a new kind of hominid, which refused to play by the rules. Without any changes in its body, and without any succession of species, it just kept changing its habits. For the first time its technology changed faster than its anatomy. This was an evolutionary novelty, and you are it.

When this new animal appeared is hard to discern, and its entrance was low-key. Some anthropologists argue that in east Africa and Ethiopia the toolkit was showing signs of change as early as 285,000 years ago. Certainly, by at least 160,000 years ago a new, small-faced ‘sapiens’ skull was being worn on the top of the spine in Ethiopia. Around the same time at Pinnacle Point in South Africa, people – yes, I shall call them people for the first time – were cooking mussels and other shellfish in a cave close to the sea as well as making primitive ‘bladelets’, small flakes of sharp stone, probably for hafting on to spears. They were also using red ochre, perhaps for decoration, implying thoroughly modern symbolic minds.

This was during the ice age before last, when Africa was mostly a desert. And yet apparently nothing much came of this experiment. Consistent evidence of smart behaviour and a fancy toolkit peters out again. Genetic evidence suggests human beings were still rare even in Africa, eking out a precarious existence in pockets of savannah woodland when it was dry, or possibly on the margins of lakes and seas. In the Eemian interglacial period of 130,000–115,000 years ago, the climate grew warmer and much wetter and sea level rose. Some skulls from what is now Israel suggest that a few slender-headed Africans did begin to colonise the Middle East towards the end of the Eemian, before a combination of cold weather and Neanderthals drove them back again. It was during this mild spell that a fancy new toolkit first appeared in caves in what is now Morocco: flakes, toothed scrapers and retouched points. One of the most extraordinary clues comes in the form of a simple estuarine snail shell called Nassarius. This little winkle keeps popping up in archaeological sites, with unnatural holes in its shells. The oldest certain Nassarius find is at Grottes des Pigeons near Taforalt in Morocco, where forty-seven perforated shells, some smeared with red ochre, date from certainly more than 82,000 years ago and perhaps as much as 120,000 years ago. Similar shells, harder to date, have been found at Oued Djebanna in Algeria and Skhul in Israel, and perforated shells of the same genus but a different species are found at Blombos cave in South Africa from about 72,000 years ago along with the earliest bone awls. These shells were surely beads, probably worn on a string. Not only do they hint at a very modern attitude to personal ornament, symbolism or perhaps even money; they also speak eloquently of trade. Taforalt is 25 miles and Oued Djebanna 125 miles from the nearest coast. The beads probably travelled hand to hand by exchange. Likewise, there are hints from east Africa and Ethiopia that the volcanic glass known as obsidian may have begun to move over long distances around this time too, or even earlier, presumably by trade, but the dates and sources are still uncertain.

Just across the strait of Gibraltar from where these bead-wearing, flake-making people lived were the ancestors of Neanderthals, whose brains were just as big but who showed no signs of making beads or flake tools, let alone doing long-distance trade. There was clearly something different about the Africans. Over the next few tens of millennia there were sporadic improvements, but no great explosion. There may have been a collapse of human populations. The African continent was plagued by ‘megadroughts’ at this time, during which desiccating winds blew the dust of extensive deserts into Lake Malawi, whose level dropped 600 metres. Only well after 80,000 years ago, so genetic evidence attests, does something big start to happen again. This time the evidence comes from genomes, not artefacts. According to DNA scripture, it was then that one quite small group of people began to populate the entire African continent, starting either in East or South Africa and spreading north and rather more slowly west. Their genes, marked by the L3 mitochondrial type, suddenly expanded and displaced most others in Africa, except the ancestors of the Khoisan and pygmy people. Yet even now there was no hint of what was to come, no clue that this was anything but another evolutionary avatar of a precariously successful predatory ape. The new African form, with its fancy tools, ochre paint and shell-bead ornaments, might have displaced its neighbours, but it would now settle down to enjoy its million years in the sun before gracefully giving way to something new. This time, however, some of the L3 people promptly spilled out of Africa and exploded into global dominion. The rest, as they say, is history.