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1 Big Migration Spawned Most–but Not All–Indigenous Americans

The views expressed are those of the author and are not necessarily those of Scientific American.

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genomics show wave of first american migrations

Image credit: Emiliano Bellini

At least 15,000 years ago intrepid Siberians crossed the newly exposed Bering land bridge to arrive in the unpeopled Americas. But was this influx the only ancient wave from East Asia? Researchers have been studying archeological, linguistic and genetic evidence for years in a quest to understand how the first Americans arrived and spread through the continents.

A new large-scale genomic study paints a much clearer picture of these early entrances and distant dispersals that led some people all the way to Tierra del Fuego in a matter of millennia. At least three major waves of migrants from Siberia hit the Americas, but not all of them have had the same reach, according to the findings, which were published online July 11 in Nature (Scientific American is part of Nature Publishing Group).

To arrive at a much-clarified historical portrait, the researchers collected genetic data from 493 people belonging to one of 52 contemporary American Indian groups from Canada to southern South America. They then compared common genetic variances with those of 245 people from 17 current Siberian groups. The key to this study was isolating the genetic variables to those that were specific to American Indian populations, which starting in the 15th century became obscured by genetic “noise” from the substantial amount of European and African influence, the researchers noted.

The initial wave, nicknamed the “First American” group, is the ancestral forebearers of every sampled group from the Yghan in southern Chile to most of Canada’s First Nations groups. But two subsequent groups, “Eskimo-Aleut” and “Chipewyan,” followed, contributing genes only to their respective Artic groups. “The Asian lineage leading to the First Americans is the most anciently diverged,” said David Rich, a geneticist at Harvard Medical School and co-author of the new paper, in a prepared statement. “The Asian lineages that contributed some of the DNA to Eskimo-Aleut speakers and the Na-Dene-speaking Chipewyan from Canada are more closely related to present-day East Asian populations.”

These later groups were apparently quick to mingle with the established populations in northern North America, so much so that Eskimo-Aleut genes sampled retained only about 43 percent of their later wave ancestor’s profiles (the rest being composed of those from the First American group)—and the Chipewyans retained only about 10 percent of their later-wave ancestry (90 percent of the variances studied belonging to the First American profile).

Based on the current analysis, very little genetic remixing appears to have occurred once groups went their separate ways throughout the continents. The exception is one group in Latin America, namely, speakers of the Chibchan languages, who live in Costa Rica, Panama and Colombia. The new genomic research shows that Chibchan speakers today carry both North and South American genetic signatures, suggesting that their ancestors subsequently moved back up the Panama isthmus.

Interestingly, the researchers also found traces of Eskimo-Aleut genetic variants in current-day coastal Siberian populations of the Naukan and Chukchi. So perhaps the Americas weren’t quite to everyone’s liking.

Katherine Harmon Courage About the Author: Katherine Harmon Courage is a freelance writer and contributing editor for Scientific American. Her book Octopus! The Most Mysterious Creature In the Sea is out now from Penguin/Current. Follow on Twitter @KHCourage.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. sparcboy 3:05 pm 07/11/2012

    Migration spawned first indigenous Americans?

    Indigenous: originating in and characteristic of a particular region or country.

    Humans are not indigenous or native to the Americas.

    Link to this
  2. 2. Mythusmage 3:45 pm 07/11/2012

    An indigene is some one descended from the first settlers, the first humans that is to settle a land.

    Link to this
  3. 3. priddseren 3:47 pm 07/11/2012

    Of course, this study leaves out any sort of genetic study to show evidence for possible migrations from polynesia, china or Europe even though there is evidence showing the possibility for all three to have occurred, especially polynesia and europeans. I know the clovis first people will start flaming even though somehow polynesians made it all the way to easter island but somehow couldnt make it to either of the two giant continents a little further on or the Polynesians having words from areas along south america for potatoes other foods in their language that should not be there.

    This article seems to show more statistical nonsense being called science. 500 people out of 52 groups out of hundreds possible and of course comparing them to Only siberian people would limit this “study” to just what the long time and possibly wrong theory that only siberians migrated. I am not implying we need to compare to every genetic line in the world but the evidence shows that other people not from siberia may have come to the americas in the same 40k to 15k years ago timeframe as the siberians.

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  4. 4. jtdwyer 5:07 pm 07/11/2012

    I agree with priddseren – there’s a foul odor in here.
    Unfortunately, a small sampling of every surviving group does not reveal every group that once lived here…

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  5. 5. eseedhouse 7:35 pm 07/11/2012

    This is science we’re talking about here so we should use the scientific definitions, not common ones. And the Scientific meaning is “Native to a particular region or environment but occurring naturally in other places as well.”, which fits the characteristics of the people found already hear by the Europeans.

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  6. 6. geojellyroll 7:43 pm 07/11/2012

    mythus: “An indigene is some one descended from the first settlers, the first humans that is to settle a land.’

    Then there aren’t any as groups migrated a dozen times. ‘Who knows who’ were the first to settle anywhere before being displaced by new migrants or moving on to more productive hunting areas etc. the Inuit were not the first group in the Arctic or the Plains Indians the first on the plains, etc.

    Link to this
  7. 7. Torbjörn Larsson, OM 8:34 pm 07/11/2012

    Interesting, confirming several entrances. Since emotions about ancestry will go high anyway, I noted this: “The name Chipewyan is, like many people of the Canadian prairies, of Algonquian origin. … Many Chipewyan believe that the name is derogatory.” [ ]

    @ sparcboy:

    With that reasoning, humans are not indigenous anywhere, since most are a mix between Moderns and Neanderthals or Moderns, Neanderthals and Denisovans. Hard to pinpoint where these groups and their mixtures originated.

    @ priddseren:

    The authors concentrated on “One contentious issue” about the number of migration streams from Siberia, which stands for the majority of the genes. That doesn’t exclude introgression. After all, with enough sampling it turned out that Neancerthals and Denisovans introgressed into Moderns.

    But if you don’t accept genetic studies, why do you care at all? That scientists will resolve issues and get to facts shouldn’t worry you in such a perspective of rejecting science and knowledge.

    Also, why start to mention (non-scientific?) evidence without providing any?

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  8. 8. Torbjörn Larsson, OM 8:42 pm 07/11/2012

    Oops. I didn’t provide the preferred term: “Denesuline (Chipewyan) speak the Dene Suline language, of the Athabaskan linguistic group.”

    Link to this
  9. 9. Cramer 1:38 am 07/12/2012

    Nicely said Torbjörn. I also could not follow priddseren’s reasoning of what he expects from science. I could only guess he is bitter to the scientific community (possibly due to AGW or evolution). It’s like criticizing Einstein’s theory of general relativity because it did not include quantum mechanics.

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  10. 10. way2ec 2:54 am 07/12/2012

    If there were genetic markers for European, African, or Polynesian ancestors would it be assumed to be of modern “mixing” and not ancient? Wish I knew more about the science involved. And even if there were landfalls made by other groups some 15,000 years ago that is not to say they were able to leave their genetics to be found today. Could a migration route along the edge of the Pacific which would not have been limited to interglacial periods be able to push back the timeline, and would the genetics reflect this? Whatever evidence they left along the coast will be underwater for who knows how long.

    Link to this
  11. 11. sparcboy 7:50 am 07/12/2012

    If humans evolved on the African continent, would that not be the only place humans are indigenous to, as they migrated from there to all other places on earth?

    Link to this
  12. 12. ea2000 12:43 pm 07/12/2012

    ” The new genomic research shows that Chibchan speakers today carry both North and South American genetic signatures, suggesting that their ancestors subsequently moved back up the Panama isthmus.”

    The author uses the term “up” when referring to a direction from south to north. This is offensive to everybody who lives in the south.

    There is no “up” on a sphere.

    Link to this
  13. 13. jtdwyer 1:30 pm 07/12/2012

    This article states:
    “Researchers have been studying archeological [sp?], linguistic and genetic evidence for years in a quest to understand how the first Americans arrived and spread through the continents.”

    If that was the objective of the referenced study, ignoring groups that might been here first but did not contibute to the genome of a later ‘indigenous’ population whose descendents have persisted to today.

    OK, so let’s consider the highly controversial Solutrean hypothesis that proposes that the earliest Americans came from France. The basis for this hypothesis is the strong similarities between stone especially spear points produced 17k-21k years ago found in Spain and France and those of the Clovis culture, which first appeared in the archaeological record in eastern North America roughly 13,500 years ago. No similar similar predecessors have been found in Asia or Alaska. The predominant spear point used in Siberia in those times was completely dissimilar, using shaped antlers with a cutting edge of inset (possibly obsidian) stones.
    Please see

    Clovis points have been found over most of North America and as far as Venezuela. The culture disappeared about the time of the Younger Dryas cold climate period around 12k years ago, along with the North American megafauna.

    So it might be possible that a large group of Europeans populated the Americas before Asian groups. They might not have ever come in significant contact. In this case, a significant earlier group of ‘indigenous’ Americans might not be represented in the existing ‘indigenous’ population’s gene pool.

    At any rate, sampling every existing distinct group of ‘indigenous’ American cultures would seem to be a somewhat reasonable approach to identifying genetic outliers, but does not produce a statistically representative sample of the current ‘indigenous’ population.

    Link to this
  14. 14. jerryd 3:43 pm 07/12/2012

    I have to agree with P and JT as they seem to leave out a lot of evidence as noise.

    There is too much evidence now that peole were here well before 15000 yrs ago.

    Much evidence is likely underwater as the ice age ended and coasts regressed 10′s to 100′s of miles farther inland, swallowing up the old living sites.

    Fla for instance was 300+ miles wider at the peak of the ice age until 20,000yrs ago before it started to shrink. Now add it was likely sea people who made it here first so their present has been wiped out likely.

    There is evidence that people had boats 50k yrs ago now.

    Link to this
  15. 15. sparcboy 11:20 am 07/13/2012

    Adding this as fuel for the debate. To my knowledge, nothing has been done to either confirm or deny:

    Do tools belonging to Stone Age hunters found on U.S. east coast prove the first Americans came from Europe NOT Asia?
    New discovery of European-style tools being heralded as among the most important archaeological breakthroughs for decades

    Link to this
  16. 16. DrPaj 10:42 am 07/25/2012

    Any Native people asked to contribute anything, OTHER THAN DNA to this discussion?

    didn’t think so……………..

    Link to this

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