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Jan 9, 2009 06:43 PM | 8
There's new evidence that the first inhabitants of North America might have arrived by both land and sea. Researchers analyzed the genetic material of modern indigenous people from North and South America to trace two rare lines back to the continents' first inhabitants. The study, published in Current Biology, provides the first genetic evidence that the ancestors of many living Native Americans took two distinct routes from Beringia (a region that included the now-submerged Bering land bridge as well as portions of Siberia and Alaska) some 15,000 to 17,000 years ago.
The new findings fly in the face of the prevailing genetic theory that just one wave of migration traveled down the ice-free Pacific coast from Beringia.
"They all arrived at the same time — it's the arrival route that's different," says lead study author Ugo Perego, a postdoctoral genetics student at the University of Pavia, Italy. Perego and his team studied genetic information from the Sorenson Molecular Genealogy Foundation in Salt Lake City, which has a large collection of genetic and genealogical data.
The new picture painted by this study shows one seafaring path to the Pacific coast and another route overland via an ice-free passageway just east of the Rocky Mountains (between the Laurentide and Cordilleran ice sheets) to the Great Lakes area. The Pacific course would have led to the rapid population of the western coasts of both continents down to Tierra del Fuego, and the land-bound travelers would have remained in the Great Plains and eastern regions of North America.
"It's interesting," says Connie Mulligan, an anthropology associate professor at the University of Florida in Gainesville. "It's the first genetic evidence that both a land and sea route may have been used." But Mulligan says more research is needed to confirm the findings, which may be explained by a population bottleneck in Beringia, during which great deal of differentiation could have occurred.
Researchers widely believe that the American migration began in Asia before crossing into Beringia — much of which is now under the waters of the Bering Sea. But there is disagreement among geneticists, archeologists and linguists about the timing, frequency and location of the movement of people from Beringia into North America. Some posit that indigenous languages were too diverse to have stemmed from a single group of people.
"Our genetic study reveals a scenario in which more than one language family could have arrived in the Americas with the earliest Paleo-Indians," study co-author Antonio Torroni, a professor of genetics at the University of Pavia, said in a statement. The two paths might also explain some of the large technological differences between regions in the pre-Columbian Americas.
In March 2008, the same team of researchers completed a massive genetic tree of indigenous American DNA, which revealed that about 95 percent of Native Americans today could trace their genetic heritage back to six individuals who lived 15,000 to 17,000 years ago. This fact, however, actually made tracing the migration routes more difficult. "Super common lineages were so common that they created a lot of background noise," says Perego. So Perego and his team used the genetic material from descendants of the other 5 percent to home in how the first inhabitants got here.
Perego hopes to soon use the more common lineages now to explore lines of expansion.
Image © iStockphoto/Oytun Karadayi
Tags:
genetics,
DNA,
Beringia,
Native American
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8 Comments
Add CommentBeringia is now under water? I don't recall it ever not being under water. At least not before the last 8 years. But still, it is B ush's fault for the global warming he has caused (what a powerful man).
Reply | Report Abuse | Link to thisAborigenes got to Australia 60,000 years ago, but only reached Europe 35,000 years ago and America 15,000 years ago. There must be some serious technological reasons for this. Or did homo sapiens sapiens get everywhere 60,000 years ago, but left no trace?
Reply | Report Abuse | Link to thisAdmittedly having very little information regarding how these studies are done AND having no "formal" training in Anthropology, I still give a lot of weight to the theories of Thor Heyerdahl. He was pooh-poohed by the "Scientific Establishment" at the time......Now, it seems that the "Establishment" is coming to the same conclusions and claiming these ideas as their own.....Hmm.
Reply | Report Abuse | Link to thisTo quote Mark Twain: "Truth is more of a stranger than fiction"
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I find it interesting that the facial features of "Indians" from the east coast of the US differ significantly from those of the "Indians" of the western US. And this was true long before recent times.
I realize that what seems "self-evident" is not sufficient grounds for scientific conclusions....but, it should point toward correct analysis.
just my 2 pesos worth......
Nobody may have crossed along the coast of Beringia before 5000 BC. The scant backwater population in NE Asia did not have the needles to sew warm-enough clothing, especially on feet and hands, let alone sufficient fuel for fire, to survive near the Arctic Circle. American Indian craniofacial features tell us more than proximate coastlines in the most uninhabitable area of the Ice Age. Accidental ocean crossings are more likely. That is why, when Columbus landed in Venezuela, he found the light-skinned Indians of Paria (near Maracaibo) dressed not too differently than the Moroccans. We have portraits of the Beotuk Indians of Newfoundland who look decidedly Caucasoid. The Mochica pottery portraits of early Peruvian kings show a mixture of marked Caucasoid and Mongoloid faces. The Aztecs were described as being of every hue of pigmentation profile. There is no convincing evidence for an early Beringia crossing. Indian noses tell a clearer story.
Reply | Report Abuse | Link to thisAztek 1: "the American migration began in Asia before crossing into Beringia — much of which is now under the waters of the Bering Sea.::
Reply | Report Abuse | Link to thisBut the Bering Land-bridge is not under water. It was washed away by the tsunami floods truggered by the earthquakes which were triggered bt the explosion of what I have called the Clovis Comet for half a century. Those tsunami floods washed away the great industrial civilizations from the Bering Valley w2hich filled with debris and the inundated ruins that survived. Those tsunami floods were a mile high, high enough to toss a large whaling boat up to the top of the highest mountain on St. Lawrence mIsland (whereI found fossilized artifacts from10.5K years ago) after demolishing their northern dams and proceeding to take out the dams and lower islands in between what are now the Aleutian Islands left over from the Aleutian Penninsula below the Farting Sea whose gassew had powered tnhe ceramic turbines that produced the Aleutian industry, and over which a technological savvy, people had reached Southwest Alaska and down into Central America long before the northern natives were swept South in their giant boats, generally filling North and West America. Until Archaelogists and Anthropologists take account of the world-wide tsunami floods triggered by the explosion of the Clovis Comet over the North Pole, the multiple entry of different peoples will mystify them. Sorry I have no more time to fill you in on all of it here. But this blog won't publish much of what I say so I doubt you will even see this:
Aztek 1: Sorry, I was in the process of giving you a full response when someone seems to habe objected to such a lengthy answer and seems to have taken it all away just as I got to pointing out the diaspora of the people of the Faroe Islands whose ruins are as sophisticated as those off Gambell Alaska. Adios Amigo!
Reply | Report Abuse | Link to thisAccidental ocean crossings are more likely. That is why, when Columbus landed in Venezuela, he found the light-skinned Indians of Paria (near Maracaibo) dressed not too differently than the Moroccans. We have portraits of the Beotuk Indians of Newfoundland who look decidedly Caucasoid. The Mochica pottery portraits of early Peruvian kings show a mixture of marked Caucasoid and Mongoloid faces. The Aztecs were described as being of every hue of pigmentation profile. There is no convincing evidence for an early Beringia crossing. Indian noses tell a clearer story."
Reply | Report Abuse | Link to thisAzteck 1: The Arctic Ocean waters flowed south on so many routes around the Northern Hemisphere, washing out multiple civilizations for which there are ruins off shore from Gambell, on St. Lawrence Island, Alaska to the Faroe Islands, They appeared to be everything from Japanese to AryN. oNE GROUP PAUSED ON THE GREAT sALT sEA OF South Texas long enough to breate a football field sized bas relief that shares many facial-cranio features of many peoples from around the world, even Barak Obama!Faroe natives mised with people down to Scotland. Hope you get it!
95% of all current Native Americans can trace their lineage back to 6 individuals! My God, they must have been going at it night and day, I wonder how they had time to hunt. And their descendants must not have turned up their noses at the idea of frequent incest.
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