Did the First Americans Arrive via Land Bridge? This Geneticist Says No:
…Raff skillfully reveals how well-dated archaeological sites, including recently announced 22,000-year-old human footprints from White Sands, N.M., are at odds with the Clovis first hypothesis. She builds a persuasive case with both archaeological and genetic evidence that the path to the Americas was coastal (the Kelp Highway hypothesis) rather than inland, and that Beringia was not a bridge but a homeland — twice the size of Texas — inhabited for millenniums by the ancestors of the First Peoples of the Americas.
This is what’s called a paradigm shift. A few years ago people would have been very skeptical of humans in the New World before the Last Glacial Maximum ~20,000 years ago. Now, most people seem to think that they were here. The evidence is too strong.
By “First People” here, does she mean current Native Americans? Or earlier extinct people?
There has been discussion on Greg Cochran’s blog (here and here) around the question of how humans could have been in the New World for so many thousands of years before Clovis and yet left so little trace. I find this quite baffling. Do you have an opinion?
As is often the case, I find this story to be overhyped (as the author, no doubt hoping for a best seller hopes it will be).
The linked New York Times coverage strongly implying that Clovis First is the paradigm was disappointing for putting up a straw man. Clovis First hasn’t been mainstream for many decades.
The important of pre-glacial melt migration is also overstated. The genetics and archaeology suggest that the pre-glacial melt, pre-Last Glacial Maximum population of modern humans in the Americas had almost no distinguishable demographic impact on a percentage basis, and also had negligible ecological impact and left few archaeological relics (in addition to a complete lack of human remains discovered so far after quite diligent study).
We are talking migrations in the low hundreds in that time frame, who mostly either died out or were demographically overwhelmed by the main Founding population of the Americas. (By the way, I like Greg Cochran’s description this population as “the Predecessors”).
Even if Paleo-Asian ancestry in South America is from the glacial or pre-glacial era (and there are good, almost irrefutable, reasons rooted in population genetics and statistics to conclude the the Paleo-Asian ancestry seen in South America can’t have anything remotely close to that time depth), the percentage of the aggregate indigenous North, Central and South American gene pools attributable to Paleo-Asian ancestry is tiny (on the order of parts per 100,000, or parts per million, or less, for a population that should benefit from a Founder effect to the extent that it was at all genetically distinguishable from the Founding population and hadn’t either collapsed before the Founding population wave arrived, or been almost completely replaced without much introgression at all by the waves of migration for the Founders).
Likewise, a coastal migration along the coast of Beringia and the Pacific Coast of North America is not all that materially different from a land bridge with a long Beringian stand-still which is the current hypothesis. No one is suggesting that people could have made a maritime trip from Northeast Asia to North America without the existence of the Beringian land bridge even if they coast hopped the trip in boats that largely stayed within sight of shore, instead of walked the distance.
The biggest really recent development that does depart from the paradigm but isn’t getting top billing in the popular press is the strong suggestion supported by genetics and archaeological evidence (and even linguistic evidence to some extent), that there were two separate waves of migration from Northeast Asia and Beringia to North America that were fairly close in time (maybe 500-2000 years apart), around the conventional pre-Clovis date for the Founding population of the Americas. The suggestion is that there was one wave of Founders largely confined to North America that is more Northeast Asian, that eventually admixed almost completely with the population from the other wave, and the other more Beringian wave being the only wave that reached Central and South America. These waves would have been similar in population genetics, but distinct enough to still leave traces in uniparental haplogroup frequencies and presence in modern populations of indigenous Americans.
The new developments also don’t alter the paradigm with respect to Paleo-Eskimo, Na-Dene, and proto-Inuit populations much later in time (basically Bronze Age and later).
These new developments also don’t disturb the conclusion that the Solutrean hypothesis (i.e. that a significant share of North Americans migrated there as a founding population by sea from Europe at around the Founding population era) is false.
Also, I take issue with the way the New York Times article describes the statement that:
She eviscerates claims of “lost civilizations” founded on the racist assumption that Indigenous people weren’t sophisticated enough to construct large, animal-shaped or pyramidal mounds and therefore couldn’t have been the first people on the continent.
In fact, the Americas have a number of “lost civilizations” of collapsed civilizations, albeit home grown and not due to European or Asian influences or to “ancient aliens”.
There was a Neolithic civilization in the Amazon that collapsed. The Cahokian culture was an empire that rose and fell, as did the empires of the Mayans, the Aztecs, the glyph building culture of the South American highlands, and the Ancient Puebloan culture, for example.
There is nothing racist about the conclusion that these relatively sophisticated indigenous cultures reached a point from which there was technological and cultural regression for a long period of time causing those cultures to be “lost civilizations” in a fair sense of that phrase.
Could it be that the reason there is no real genetic trace of the pre-Clovis settlers is that both the earlier and later settlers were closely related groups from Beringia?
@Walter Sobchak
I don’t understand this fully but here are my 2 cents. The Amerindian populations experienced initial founder effects and bottlenecks, so the Beringian groups that they came from would be very specific. If they mixed with previous groups, then that signal would probably be clearer to see because of this.
If previous groups like the Australasian signal did exist in the Americas before the Beringians arrived, maybe they were almost entirely wiped out or died out before most of the incoming people could interact with them.
@Presto “By “First People” here, does she mean current Native Americans? Or earlier extinct people?”
The intent is to refer to all Pre-Columbian inhabitants of the Americas, and their descendants, who had a sustained presence in the Americas, with the exception of the Vikings who made a brief sojourn on the Northern part of the Atlantic coast of North America and possibly also in the Hudson Bay area (before their short lived colonies collapsed) ca. 1000 CE, temporary Polynesian visitors to the Americas via the Pacific Coast of Central America and South America (ca. 300 CE or later), and possibly other relative recent encounters from outside the Americas in relatively recent times that are not as well documented.
These conjectural contacts might include a claim supported by some archaeological and legendary history evidence of a two hundred year long South American coastal city state dynasty (ca. 900-1100 CE) that may have involve a small number of East or Southeast Asian families that arrived in the pre-Columbian era, and one outlier study which claims to have radiocarbon dated a New World custard apple found in India to ca. 2000 BCE. (Pokharia, Anil Kumar; Sekar, B.; Pal, Jagannath; Srivastava, Alka (2009). “Possible evidence of pre-Columbian transoceaic voyages based on conventional LSC and AMS 14C dating of associated charcoal and a carbonized seed of custard apple (Annona squamosa L.)”. Radiocarbon. 51 (3): 923–930.).
In particular, the term “First People” definitely includes Paleo-Eskimo ancestors of the modern Na-Dene peoples who arrived in North America ca. 3000 BCE-2400 BCE, see, e.g., Flegontov et al., Na-Dene populations descend from the Paleo-Eskimo migration into America,bioRxiv (September 13, 2016), and members of the Birnirk and Thule cultures whose descendants include the modern Inuits who arrived in North America ca. 650 CE to 850 CE, in addition to the main waves of the Founding population of the Americas ca. 14,000 years ago, and the Predecessors, i.e. the modern humans who arrived in the Americas earlier than that (apparently at least 22,000 years before present).
“First people” is the preferred Canadian description of people who would be called “Native Americans” and “Alaska Natives” on U.S. Census forms, and who were previously called (and sometimes still are as a result of established legal terminology) called “Indians” (because the Conquistadors were idiots in this respect).
Completely off topic, but I just saw the NYRB’s piece on EOWilson, etc. Its mention of RK put me in mind of this movie scene. Congratulations.
The NYRB piece on Wilson is paywalled, but there is an open copy here.
I notice her book has a land acknowledgement at the beginning.
The NYRB piece made me think there could have been a a similar article in a Christian publication, “Wilson helped people who were known atheists who wanted to turn America into a pagan society.”
Can’t read the article and don’t have the book; are we talking about maritime migration before the LGM, or multiple migrations, or what?
The Beringian land bridge was exposed for most of the period since 70 000 years ago, IIRC, and certainly for a long time before the LGM. The Laurentide and Cordilleran ice sheets did not coalesce to form a glacial barrier stretching across Canada till the LGM, last I heard ~23 000 years ago. So there was a very long window with a land bridge but no ice barrier.
If people were in New Mexico 22 000 years ago they could, and probably did, enter North America during this window. You could argue for the maritime route on other grounds, I guess. Or more than one migration.
“The linked New York Times coverage strongly implying that Clovis First is the paradigm was disappointing for putting up a straw man. Clovis First hasn’t been mainstream for many decades.”
And Americanist linguists basically never accepted that model.
“In particular, the term “First People” definitely includes Paleo-Eskimo ancestors of the modern Na-Dene peoples who arrived in North America ca. 3000 BCE-2400 BCE, see, e.g., Flegontov et al., Na-Dene populations descend from the Paleo-Eskimo migration into America,bioRxiv (September 13, 2016)”
This is interesting if it’s true but it conflicts with other lines of evidence. Athabaskanists posit a time depth of 6,000 years for the Na-Dene languages, which is not a claim about the time depth of the populations, but you see the obvious problem. There is consensus now on both sides of the proposal, Athabaskaninsts and Yeniseianists, that those two families are genetically related. As for Eskimo-Aleut languages, the appears to be some connection with Uralic languages.
That certainly doesn’t preclude a biological connection between the two groups – or within one group speaking unrelated proto-langugaes. But there’s some ‘splainin’ to do.
“I notice her book has a land acknowledgement at the beginning.” So very PC in all things indigenous, as is necessary if you’re an academic. She’s even afraid to spell out the word Eskimo, as some now consider it a slur. Most people have a vague, but positive view of Eskimos, as a people who survived in a very difficult environment, but that must be an evil prejudice if you can’t learn the new vocabulary.
“She’s even afraid to spell out the word Eskimo, as some now consider it a slur. ”
I think it’s considered a slur mostly in Canada. I have heard Canadians insist that the proper term is “Inuit”, which is inaccurate since the Inuit are only one of those people’s. The term doesn’t cover the Yup’ik or the Alutiiq, fr instance.
“Athabaskanists posit a time depth of 6,000 years for the Na-Dene languages, which is not a claim about the time depth of the populations, but you see the obvious problem.”
Not really. 3000 BCE puts you at a time depth of 5000 years, the MOE in time depth estimates (especially linguistic ones) is considerable, the MOE in the archaeological time depths is about ± 300 years and biased towards older rather than younger, and some of the time depth can be attributed to NE Asian diversification before arriving in North America. So, the linguistic picture is reasonably consistent with the archaeological and genetic stories.
Eskimo is disfavored as marginally derogatory in most current U.S. academic writing, especially outside the technical construction with a very specific meaning of Paleo-Eskimo (which gets a pass for similar reasons to a term like Indo-Aryan). It has roughly the same status as “Gypsy.” You might mention “Eskimo” as an alternate description early on in an introduction for the benefit of lay readers not familiar with modern terminology and for continuity for someone doing word searches based upon terms on older scholarship, but both are disfavored as primary descriptions in academic writing.
If I were advising someone in the U.S. on what terminology to use in an academic anthropology or genetics paper that the person wanted to publish in a peer reviewed journal, or in a master’s thesis or PhD dissertation, I would discourage them from using that term as their primary descriptor for people who are descended from the Thule civilization or closely related civilizations in North America.
When you are describing living groups of people, it is appropriate to use terms that they themselves are most comfortable with as a matter of civility and courtesy.
Sometime ago, you asked for suggestion about guests for the podcast. The comments for that thread are now close, so allow me to make my suggestion here instead.
While on youtube, I stumbled upon an interview with Dr. Lee Clare, research co-ordinator and archaeologist in charge of the excavations at Göbekli Tepe. He does social media and I’m sure you would have interesting question to ask him.
“Not really. 3000 BCE puts you at a time depth of 5000 years, the MOE in time depth estimates (especially linguistic ones) is considerable, the MOE in the archaeological time depths is about ± 300 years and biased towards older rather than younger, and some of the time depth can be attributed to NE Asian diversification before arriving in North America. So, the linguistic picture is reasonably consistent with the archaeological and genetic stories.”
Yeah, that works. I haven’t seen what that linguistic time depth is based on and I doubt I’d be able to evaluate it anyway. However the diversity probably arose in northwestern Canada and Alaska, since it’s unusual for populations to split and then migrate in parallel to some new area. In the spread of language families I can’t think of one example of that happening.