By Sid Perkins
What a juxtaposition: About 800 million years ago, East Antarctica, now one of the coldest regions on Earth, abutted what is now California’s Death Valley, one of the hottest.
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Both locales were part of an equatorial supercontinent called Rodinia, says John Goodge, a geologist at the University of Minnesota Duluth.
The motion of tectonic plates continually rearranges Earth’s continents, sometimes cramming most or all of them into immense groupings called supercontinents.