The Next SupercontinentAn internationally recognized scientist shows that Earths separate continents, once together in Pangea, are again on a collision course. Youve heard of Pangea, the single landmass that broke apart some 175 million years ago to give us our current continents, but what about its predecessors, Rodinia or Columbia? These supercontinents from Earths past provide evidence that land repeatedly joins and separates. While scientists debate what that next