A research team reports new findings of stone age tools that suggest humans came “out of Africa” by land earlier than has been thought. Geneticists estimate that migration from Africa to South-East Asia and Australia took place as recently as 60,000 years ago. But Dr Michael Petraglia, of Oxford University, and colleagues say stone artifacts found in the Arabian Peninsula and India point to an exodus starting about 70,000 to 80,000 years ago - and perhaps even earlier, reported BBC News. Petraglia, whose co-workers include Australian and Indian researchers, presented his ideas at the British Science Festival, which is hosted this year at Aston University. “I believe that multiple populations came out of Africa in the period between 120,000 and 70,000 years ago,” he said. “Our evidence is stone tools that we can date.” Most of the tools are from far inland - hundreds of kilometers from the coasts. This means it was more likely humans migrated by land than in boats, he said. The tools are found in areas that are often very inhospitable now, but which at the time would have been much more conducive to migration. “During the period we're talking about, the environments were actually very hospitable,” he told BBC News. “So where there are deserts today, there used to be lakes and rivers, and there was an abundance of plants and animals.” The team found the stone tools in layers of sediment that they can date using sand and volcanic material found above and below the implements. The tools were mainly either spear heads or scrapers. In particular, some tools were sandwiched in ash from the famous Toba eruption that geologists can date very accurately to 74,000 years ago. The team thinks that the tools it has found are the type made by modern humans.
