America Before

Until very recently, there was almost universal agreement amongst scientists that human beings first entered the Americas from Siberia around 13 000 years ago by walking into Alaska across the Bering land bridge. Over the next two thousand years, their descendants supposedly spread out through Central and South America reaching the southern tip of Chile. Meanwhile, the Ice Age ended, the sea level rose, the Bering land bridge was submerged, and the Americas were isolated from the rest of the world.
Largely because of this consensus, there has not been a single serious attempt in modern scholarship to investigate the possibility that the Americas might have played an important part in the still incomplete story of human origins, or in the equally incomplete story of the origins of civilization.