About 250 million years ago, at the end of the Permian period, something killed some 90 percent of the planet's species. Less than 5 percent of the animal species in the seas survived. On land ...

The mass extinction that ended the Permian geological epoch, 252 million years ago, wiped out most animals living on Earth.

Map showing respective Permian Basin acreage positions of Diamondback Energy (red) and Double Eagle ... [+] (blue). Andrew Dittmar, Director at Enverus, said in an email that the deal means ...