July 12, 2012

Paleo-Indians arrived before Clovis

Earliest Americans Arrived in Waves, DNA Study Finds

By Nicholas WadeNorth and South America were first populated by three waves of migrants from Siberia rather than just a single migration, say researchers who have studied the whole genomes of Native Americans in South America and Canada.

Some scientists assert that the Americas were peopled in one large migration from Siberia that happened about 15,000 years ago, but the new genetic research shows that this central episode was followed by at least two smaller migrations from Siberia, one by people who became the ancestors of today’s Eskimos and Aleutians and another by people speaking Na-Dene, whose descendants are confined to North America. The research was published online on Wednesday in the journal Nature.
Native Americans migrated to the New World in three waves, Harvard-led DNA analysis shows

By Carolyn Y. JohnsonAn exhaustive study of DNA taken from dozens of Native American groups that span from Canada to the tip of South America is helping to settle a question that has long divided scientists: When people arrived in the Americas more than 15,000 years ago, the Harvard-led research shows, they came in successive waves, not all at once.

The analysis published Wednesday reveals that while one population of “First Americans” crossed a land bridge from Siberia during the last Ice Age, giving rise to most Native Americans, there were at least two subsequent migrations. These people mixed with the founding group later, leaving traces of their genes in the DNA of present-day populations in Alaska, Greenland, and Canada.
A related report bolsters the evidence that the prevailing Clovis First theory is wrong:

Spearheads and DNA Point to a Second Founding Society in North America

By John Noble WilfordStone spearheads and human DNA found in Oregon caves, anthropologists say, have produced firmer evidence that these are the oldest directly dated remains of people in North America. They also show that at least two cultures with distinct technologies—not a single one, as had been supposed—shared the continent more than 13,000 years ago.

In other words, the Clovis people, long known for their graceful, fluted projectile points, were not alone in the New World. The occupants of Paisley Caves, on the east side of the Cascade Range, near the town of Paisley, left narrow-stemmed spear points shaped by different flaking techniques. These hunting implements are classified as the Western Stemmed Tradition, previously thought to be younger than the Clovis technology.
Comment:  Non-scientists have used the Clovis First theory against Indians in a couple ways:

1) They claim the late arrival of the Paleo-Indians gives them less ownership of the land. Especially if they can prove Europeans were here at the same time (Kennewick Man) or predated the Clovis people (Solutrean hypothesis).

2) They claim Paleo-Indians killed North America's megafauna because the animals disappeared roughly when the Clovis people arrived. Thus, Indians don't deserve to be called environmentalists and stewards of the land.

Now science is demonstrating that the Clovis weren't the first or only people in North America. And these anti-Indian claims are crumbling to dust. Oops.

And this may be only the tip of the iceberg. How do we know tens or hundreds of people didn't migrate from Asia before this? They could've come by land or sea 25,000 or 50,000 years ago.

After all, people first crossed the ocean to Australia some 40,000-60,0000 years ago. Crossing the Bering Strait and traveling down the Pacific coast doesn't seem any more difficult.

Are the genetic and linguistic tests sophisticated enough to detect the minute presence of earlier migrations? I.e., people who arrived tens of thousands of years ago and left little or no physical evidence? I don't know, but until someone answers that question, I'd say the earliest migration date remains unknown.

For more on migration theories, see Clovis First Theory Disproved and Polynesians Visited Before Columbus?

Below:  "This sketch illustrates an initial migration into America along a coastal route, followed by two subsequent Asian migrations that mixed with the first migrants to give rise to a number of present-day North American populations." (Emiliano Bellini)

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