National Geographic News, Reporting Your World Daily

Monday, November 23, 2009

Photo: "Nanodiamond" Find Supports Comet Extinction Theory


Email to a Friend	<< Back to Full Story

The discovery of tiny "nanodiamonds" support a controversial theory that a catastrophic swarm of comets caused the extinctions of several ice age mammals, including the woolly mammoth (above, an artist's rendering), scientists said in January 2009.

But some experts say the diamonds are not proof of an impact.

Illustration courtesy of Charles R. Knight/NGS