BOSTON, Aug. 7 (UPI) -- U.S.-led scientists say they have found the last traces of tundra that grew in interior Antarctica before temperatures dropped millions of years ago.
The National Science Foundation-funded researchers said an abrupt, dramatic climate cooling during an approximately 200,000-year span -- a relatively brief period of geological time -- occurred about 14 million years ago, forcing the extinction of tundra plants and insects and transforming the Antarctic interior into a perpetual deeply frozen region.