Wegener's "The Origins of Continents and Oceans" propounded that all of the world's continents had once been joined together in a vast supercontinent, called Pangaea that means all the earth, and that about 200 million years ago Pangaea began to split apart, and the land pieces drifted apart to other locations on the globe. In 1596, a Dutch mapmaker, Abraham Ortelius, also suggested that America, Eurasia and Africa were once joined and drifted apart "by earthquakes and floods" that created the modern Atlantic Ocean. Extensive evidence in the form of fossils of plants and animals of the same age found in different continent shores suggested that these shores were once joined. Wegener's theory also received support from South African geologists Alexander Du Toit and Arthur Holmes' theory of plate tectonics. The theory says that huge plates, several miles thick, lie under Earth's continents and oceans. As heat rises from deep underground, these plates move. This action is known as plate tectonics, and it explains how the continents have drifted apart in the past and continue to drift today. This shows that, though Wegner had some of the details wrong, his basic idea was way ahead of its time.