19 November 2009 by Jeff Hecht
Was there a Stone Age apocalypse or not? One narrative has it that about 13,000 years ago a comet blasted North America, wiping out the continent's megafauna – as well as its early settlers.
It's a compelling story, offering a simple explanation to the mystery of why mammoths, mastodons, and Clovis humans vanished. But it's a controversial theory, and new research suggests the impact was far too small to have done any serious damage.
Doubts centre on the speed of extinctions, the fate of the Clovis culture, and the presence of supposed impact signatures. But advocates of the comet-blast theory say they will present their own new data at the American Geophysical Union (AGU) meeting in San Francisco, where they will share the stage with sceptics.
"Nothing special happened at 12,900 years ago," says John Williams of the University of Wisconsin-Madison. His data, reported in Science this week, suggest that large mammals were already rare well before the purported impact.
Read full story at: http://www.newscientist.com/article/dn18175-was-there-a-stone-age-apocalypse-or-not.html
(Submitted by Tim Chapman)
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