The theory of continental drift by Alfred Wegener states that all land masses were originally united in a single supercontinent known as Pangaea (250 million years ago). He shows evidences like continental fit, similarity of rock sequences, glacial till and striations, fossils (cynogathus-land reptile, lystrosaurus-land reptile, mesosaraus-freshwater reptile, glossopteris-fern plant) to support his theory but what was lacking is that it lacked a mechanism to explain HOW the continents moved apart. But Harry Hess, a geologist and Navy submarine commander during WWII brought up a new evidence to add in support of Wegener’s theory: the idea of seafloor spreading and magnetic reversals.