North and South America were totally empty of people until the first arrivals from Siberia crossed a land bridge into Alaska, spreading in a few thousand years to the tip of South America. The genetic study may help settle a debate between a long-held view that the populating of the continents came as one event instead of the more recently supported notion, backed by this study in the journal Nature, that the migration happened in three distinct waves.As far back as I can remember in graduate school, I was taught that there were at least two, probably three migrations. The two that I remember studying were from the Lena River Basin in Siberia and the Amur River basin, on the border of Russia and China. There were probably more than that, as there are some Native American populations that have gene fixation for certain blood types, a situation that would only occur in a drift/founder effect situation. I remember Dick Jantz teaching us this twenty years ago, at UT.
"Our study makes clear that mixing of these three ancient populations is the story of Native American arrival," says geneticist David Reich of Harvard Medical School, lead author of the study.
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Good post, Jim.
ReplyDeleteA related story about Clovis people probably not being alone in North America also points to at least two migrations is found here:
http://www.nytimes.com/2012/07/13/science/clovis-people-werent-alone-in-north-america-spearheads-and-dna-suggest.html
I can't help but wonder if these data about other populations on the North American Continent alongside or even prior to the Clovis people could be related to the Kennewick Man found in the Columbia River gorge in 1996. Craniometric morphology of those remains is distinctly different from the ancestors of current American Indian populations, having greater similarity with contemporary Ainu or Polynesian than with either Europeans or American Indians.
Taken together, these all mean that the archaeology of the Americas remains a research area where there is still much left to be discovered.
Also you have a dead link inside the word "these" in paragraph 2 of the pull quote.
Yes, thank you. I use the old blogger interface because I like it and it interfaces with Foxytunes but every so often, it randomly, and for no apparent reason, sticks in the HTML for the Blogger gif. Usually, I can spot it. This time I did not.
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