Mega-eruption 'not as bad as we thought' July 06 2007 at 11:30AM
Washington - One of the biggest eruptions in Earth's history some 70 000 years ago, the Toba volcano in Indonesia, was not as much a world climate catastrophe as first thought, a study said on Thursday.
The Toba eruption, in northern Sumatra, was the strongest felt by the planet in the last two million years, said an international team of scientists.
However, the hypothesis that it may have drastically cooled the Earth, killing off most of the human population living at the time, has only been supported by flimsy evidence, they said in a study published on Thursday in Science magazine,
A series of stone artefacts unearthed in southern India now suggest that local human populations remained in the region after the Toba eruption, the scientists said.
The prehistoric tools were found in sedimentary layers sandwiching a layer of ash produced by the Toba eruption. The tools above were essentially at the same level of evolution as those below, the scientists said.
The small difference between the two indicates that the impact of the Toba eruption was not as significant as earlier thought. The sophistication of the tools suggests they were made by modern humans rather than earlier relatives.
The scientists said that while more research was needed, the finding could clarify some aspects of human migration during the time period.
The team of scientists was led by Michael Petraglia of Britain's University of Cambridge, and included experts from Britain's University of Reading, the US Smithsonian Institution, India's Karnatak University, and Australia's University of Queensland and University of Wollongong.
http://www.int.iol.co.za/index.php?set_id=1&click_id=588&art_id=nw20070706111910209C966137
