National Geographic News
With the tell-tale sheen of heat-treated rock, a 72,000-year-old cache of stone weapons found in Africa suggests humans began using fire to create tools nearly 50,000 years earlier than previously thought, a new study says.
Scientists had thought people began manipulating fire to create tools in Europe about 25,000 years ago.
But the new finds suggest that people in what is now South Africa discovered that heating a stone called silcrete would make it easier to flake, allowing them to shape more advanced blades, knives, and other tools.
These early engineers likely used some of these tools, mounted on handles, to hunt and butcher wide range of prey, from the aggressive Cape buffalo (Cape buffalo picture) to the tiny mole rat, according to the authors of the study, to be published tomorrow in the journal Science.
Birth of Modern Humanity?
This sophisticated control over fire reflects advanced smarts, and marks the turning point when we became "uniquely human," said study leader Kyle Brown, an archaeologist at the University of Cape Town in South Africa.
"These people were extremely intelligent," Brown said. "These are not the image of the classic cavemen, of brutish people that are stumbling around the landscape and, in spite of themselves, surviving.
"These are the people that [may have] even colonized the rest of the world," he said.
As part of the study, the researchers replicated the processes the early Africans likely would have used to make the stone tools. Heated over a fire pit, the silcrete flaked and took on a glossy red color.
Such craftsmanship required thinking ahead, a sign of high intelligence, Brown said. People had to collect firewood, build the fire, work the stone, and then afix the handle to the stone using natural adhesives.
"Because [this is] such a sophisticated technology, this is something that would involve language to pass it on to the next generation," he added.
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