Scientific Origin Stories II::

Migrations

As no pre-Homo Sapiens Sapiens has been found in the Americas, most scientists have assumed that humans did not evolve there. Studies in such subjects as archaeology, linguistics and physical anthropology, for example, have conferred that the present-day Native Americans originated in the vast regions between Siberia and Mongolia.

The earliest descendants of the hundreds of Native American nations today are thought to have crossed, in several waves of migration, a land bridge over the Bering Strait from eastern Asia to Alaska, perhaps 30,000, 15,000, even 10,000 years ago. There is evidence that as recently as 3000 BC, descendants of today's Aleuts and Athabascans of Arctic Canada were crossing the Bering Sea by means of dug-out canoes, skin boats or by walking across the winter ice sheets. The Inuit are believed to have been still arriving in Canada as recently as 1000 years ago.

The date of humanity's arrival in the Americas is open to much discussion and controversy. Certainly, geologists have identified two periods between 75,000 and 45,000, and then 25,000 and 14,000 years ago when the Bering land bridge was exposed. Others have recently claimed that the land corridor was closed between 30,000 and 12,000 years ago, positing coastal migration theories for this period. There is even the possibility that some human groups entered America before 30,000 BP. Until recently, the general consensus seems to have been that humans arrived in the Americas around 12,000 years ago. But one must be aware that, in recent years especially, some archaeologists have asserted a much earlier migration date than the conventional 12,000 years BP: suggesting 20,000 to 30,000 BP to be closer to the truth for human origins in America. This shall be discussed shortly. Furthermore, some linguists have suggested that the great diversity of Native American languages (some 142 so-called 'New World language families' exist to date) needed at least 30,000 to 40,000 years to diversify and develop in such complex ways on the American continent.

A conventional hypothesis runs as thus: During the Ice Age, Beringia (the land mass that connected Siberia to northern America) hosted many different and diverse cultural and even genetically-mixed groups, each of whom had adapted to a variety of environments: mountain, maritime, tundra and river valley. From these diverse Asian groups, small bands of big-game hunters and their families followed herds of large Ice Age game along the eastern Asian coasts and occasionally across the land bridge into the Americas.

Some biologists cite evidence that suggests a relationship between the teeth of humans from northern China and those of prehistoric humans from North America; relationships have been found between the flora and fauna of northeastern Asia and the Americas; and other controversial studies have found developmental relationships between the skulls of prehistoric Americans and modern Mongolians and Native Americans. There is, however, no consensus that today's Native Americans were necessarily specifically Mongoloid, as eastern Asia itself was ethnically- or genetically diverse during the apparent period of American migrations.