My dad used to make this argument: of all the millions of footprints that humans made, after arriving in North America, what is the likelihood that we found the very first of those footprints?
The point is, whatever evidence we find, it's unreasonable to think that evidence we've found is the first evidence that existed, so we have to assume the real arrival was a bit before that. When we had evidence of humans arriving 17,000 years ago, it was reasonable to assume humans really arrived 21,000 years ago. When we have evidence of people arriving 23,000 years ago, you have to assume people really arrived 25,000 years ago.
There may come a point, centuries from now, when our evidence feels comprehensive, at which point the error estimate can shrink. But modern archeology is barely 100 years old and most subject areas are still under-studied, so error estimates need to remain large, for now, especially for the prehistoric era. (Obviously error estimates are much smaller for the historic era, where we have a relative abundance of evidence.)
This is actually how archeologists estimate their ranges for human habitation in an area, just with math instead of guesses. This paper isn't about that (try timing papers like [1] instead), it's about the actual radioisotope boundary dates for an actual site.
Part of the problem these LGM dates keep running into is that it's not obvious how people got here in the first place. After about 48kya, the ice free corridors close up and the ice sheets encompass most of the coastal islands as well until about 22kya when humans can get to Alaska again and 18kya when humans can easily get down the coastal routes. What would have been possible in the middle is very much still in the ??? grey area.
I assume they built boats. It isn't exactly surprising after 20k years that we can't find any proof of these boats, but how else would then have come across? Fly?
We know that humans had boats by that point due to their presence in Australia and the current dominance of the coastal migration hypothesis. The problem is that our current understanding of the climate is that the coast was too ice-locked by glaciers for coastal foraging. If there's something this old, either they were doing some very impressive and unexpectedly long distance nautical journeys, or there are gaps in the details of our paleoclimate models.
It's not that either is impossible or even improbable, it's just that it forces us to revisit everything again to try and work out the routes if these (and other similarly early dates that have been proposed in the last couple years) hold up under review.
Coastal foraging? Why can't they just fish? There are lots of fish in those northern reaches today, I assume there would have been even more back then. And fish doesn't necessarily have to be cooked, so no requirement to stop to make fires.
Note that the phrase "coastal foraging" typically implies fishing and the exploitation of other littoral/marine resources.
Anyway, the current understanding of the paleoclimate is that entire region between approximately Valdez and Vancouver Island was entirely covered by glaciers out to the edge of continental shelf until ~18kya. Lesnek et al has some good diagrams [1]. Living exclusively off deep-sea marine resources in an iceberge minefield without fire for over a thousand miles in one of the coldest, most dangerous oceans in the world without landing suggests an unprecedented level of both nautical technology and experience. Where did that come from? We have no good answers right now.
What is the reasoning for thinking they came from the top? You’ve said they had already reached Australia via boat. Couldn’t they have reached some other part of the Americas by boat, maybe South America via Africa or Easter island?
Mainly because both Americas where inhabited way before the pacific islands. For example Easter Island is estimated to have been inhabited around 300 to 1200 CE. This is also confirmed by genetics, with an origin of the Amerindians located around central Siberia.
We've definitively established that Clovis populations and all modern Native Americans are genetically related to Beringian populations out of Eurasia. It's reasonable to suspect pre-clovis populations probably came from much the same area, especially given that suggested pre-clovis lithics so closely resemble clovis traditions.
Additionally, the farthest east that we've found evidence of Australasian populations is the Solomon islands, some 7,000+ mi from South America. There's no evidence of habitation on the intervening islands until Austronesian peoples show up much later. As for Africa, we simply have no evidence for it whatsoever.
The authors' speculation that this was due to both populations originating in east Asia eventually turned out to be true once further work was done on sequencing Tianyuan man [1]. It's not indicative of Pleistocene trans-pacific contacts.
One point in favor of a water route is you can carry a lot more stuff that way. Most of the migrations into the Americas were before animals other than perhaps dogs were domesticated and before the wheel was invented.
So anything you wanted to bring with you on a land route had to be carried by humans, dogs, or pulled on sleds by humans or dogs.
On a water route you could tow another boat or raft behind full of your stuff. (Rope was invented long before any migration to the Americas).
But now they are saying that people were here before the land bridge was usable or existed, right? So, maybe they came some way other than the land bridge. Or, earlier peoples came via some other route (hence the current footprints) and then a later migration came via the land bridge.
And possibly more raw intelligence as we have mainly been selecting for "smarter than grass" since beginning this experiment in agriculture 10k - 20k years ago.
Technically true but wrong. If your oldest Facebook post is from 2015, how likely is it that you've been using the internet before 2005?! Archeologists are very smart people in their own right, some are much smarter than we are. They do consider everything that we think they haven't. Let's give some benefit of the doubt to our fellow researchers.
I first joined facebook in 2009, but have been on the internet since 1991.
You might counter that facebook only started in 2004, and didn't get much traction until 2006. But I was invited before that and simply didn't care to join, preferring to occupy other parts of the `net.
Likewise, Clovis artifacts all date from after the peak of the last ice age, when glaciers were melting, land routes were opening, and sea levels were rising to obliterate any coastal artifacts from any previous waves of migration.
Clovis-first has been debunked for decades. This is just another - particularly solid - nail in that theory's coffin. It is worth asking why it has persisted so doggedly. I don't think it is because archeologists aren't very smart people.
WTF is this? I was at university and I assure you we were connected to the internet. I got a login and an email address from the physics department in `91 because I was working on a project on their network. I used Elm for email, which had been out since the 80s. I was happy to upgrade to Pine (Pine is not elm) in 1992 and actually kept using Pine until like 1999. By `92 pretty much everyone else at my university was using the internet. I could dial up from home via modem, and check my email. NCSA Mosaic came out in `93.
>ure, but I was a network engineer at the time and your TCP/IP was very, very niche.. you know very well that there was no "Internet" in 1990
There was no consumer Internet in 1990.
However, TCP/IP was in use across a broad range of academic institutions and corporations, and it was possible for pretty much anyone to buy access to TCP/IP-based inter-networks.
Which, if you were a network engineer (and not for Novell or DEC) at the time, you would know.
direct dial to BBS, at least that was the "internet" for me at that stage. The disparate nodes of bulletin boards wasn't what I would call an internet. And it was very cliquish.
Some background on this, there is a long standing back to the late 20th century - and to those of us outside the field darkly funny - controversy within this particular scientific community on when the first humans arrived, which can be broadly googled by searches for "Clovis man controversy".
Sure archeologists are very smart people, and like all other very smart people, can still be caught on the wrong side of history as new evidence piles up against existing theories.
> If your oldest Facebook post is from 2015, how likely is it that you've been using the internet before 2005?!
Who knows. It could be that person has been using the Internet for a very long time and is thus a late adopter of Facebook due to preferring to do things the old way. It could also be a person who started using the Internet in 2015. GP's point that we really can't conclude anything beyond a lower bound isn't falsified by your example
>They do consider everything that we think they haven't.
This can be said of almost any observation made about a particular field of research. Outsiders aren't familiar enough with the current state of research and they often assume experts haven't considered some rather obvious things.
That's not to say that outsiders shouldn't participate in the discussion, but they should acknowledge that there is a good chance their ideas have already been considered.
> If your oldest Facebook post is from 2015, how likely is it that you've been using the internet before 2005?!
My Facebook account dates back to 2015, but I have been using the internet since the mid 90s. (As far as I'm aware, there's no evidence of the previous account I had from 2006-2010ish)
> Let's give some benefit of the doubt to our fellow researchers.
Clovis first persisted for almost the entirety of that 100 years despite large and ever growing amounts evidence to the contrary.
There is no need for "error estimates to remain large". The field just needs to acknowledge the actual numbers the evidence gives, instead of ignoring things when the show up because they are older than expected and don't fit with the existing narrative.
The linked article has a footprint in New Mexico 23,000 years ago, whereas your link is in the top of Alaska at 24,000 years ago. It sounds like filling in the middle will be quite exciting!
> The footprints were formed when people strode over damp, sandy ground on the margin of a lake. Later, sediments gently filled in the prints, and the ground hardened. But subsequent erosion resurfaced the prints. In some cases, the impressions are only visible when the ground is unusually wet or dry — otherwise they are invisible to the naked eye. But ground-penetrating radar can reveal their three-dimensional structure, including the heels and toes.
USGS describes the site as a "large playa," and the Science abstract says they were "stratigraphically constrained and bracketed by seed layers" so I interpret that to mean they were made in wet sand and buried under layers of more sand.
(I wonder how much had paid NY Times to the scientists that discovered the footprints. If you want support science shouldn't you see the photos and read it in the scientific journal instead?)
Expect this to get messy. There are powerful interest groups whose self-identity relies on Clovis culture and its descendants being the first peoples of the Americas.
Uh... who? I mean, yes, it's true that almost all native americans (the exceptions being the Inuit and their relatives who are more recent immigrants) are descendants of a single wave of population motion out of asia about 12kya that coincides closely with the Clovis culture.
But hints that there were people here before that have been around for a long time, starting with the Monte Verde work in Chile a few decades back.
And I don't recall any particular "mess" from indigenous americans.
I mean, scientifically there's definitely a big question of why the population density of the earlier settlers seems to have been so low (vs. clovis, which basically exploded onto the scene and went everywhere on the continent very fast), or why they are not identifiable in contemporary DNA (which very closely supports the "clovis only" hypothesis).
Just to clarify: you're saying that genetic analysis appears to rule out current natives being (at least partially) descended from a pre-clovis population?
Correct. The evidence isn't exactly overflowing but what little there is indicates the Clovis migration was not a peaceful one and existing populations either met a violent end or were forced to move to areas where their populations couldn't be sustained and slowly died out.
The parallels to the European genocide of Native Americans has significant consequences to two groups of people. The first is the white supremacists/edgelords who think an invasion from thousands of years ago means the actions of colonial Europeans as well as ongoing social justice issues with native Americans/reservations are somehow justified or deserved. The second is the far larger but far less dangerous group of people who think native Americans are somehow inherently morally superior and/or that European colonialism is responsible for all the world's problems. To them it's an article of faith that aboriginal peoples do not and cannot commit large-scale atrocities.
These two groups can make discussing and teaching American pre-history very difficult.
I don’t understand how it would be possible for the Clovis culture to conquer an earlier people without leaving a genetic record. I mean we even have Neanderthal DNA in each of us. Surely they would have intermingled?
One answer would be that there was no conquering. That could happen via a few possibilities:
1. pre-Clovis people were so thinly spread that Clovis was able to just fill in the gaps
2. pre-Clovis people had actually essentially become extinct before Clovis arrived. It's not easy to see how that would be the case in a continent(s) of this size, but not actually implausible.
3. as a combination of the two, pre-Clovis culture was completely nomadic, and their constant migration kept them out of the way of Clovis until a point where their population was so diminished as to leave no descendants, even via inter-breeding.
Who are these interest groups? My understanding is that pre-Clovis is completely established beyond any semblance of reasonable doubt, so they're 30+ years behind the times.
From what my archaeologist friends in North America tell me, the interest group is modern native Americans. They are the direct descendants of the Clovis culture.
Clovis-Americans have certain unique rights based on legal theories that their ancestors were the first human occupants of the land, which would be weakened or voided if substantial scientific evidence established that they simply replaced a prior human culture. Due to a perverse set of incentives, native American interest groups use these unique rights to actively interfere with archaeological research that might undermine their claims to being the first occupants of the land. While it has not stopped pre-Clovis research, it has greatly impeded it.
While the scientific evidence strongly suggests a pre-Clovis people, the legal theories and legislation that presume this is not the case are still active. These are evaluated on a case by case basis currently.
I'm a (formerly working) archeologist. Native American land claims are horrifically complicated and way beyond my knowledge, but I'm not aware of anything that's legally based on the scientific consensus about the earliest inhabitants of a specific area. Instead, the term you'll commonly find used is "aboriginal title", which basically just means "we've been here a long time". It's as deliberately vague as it seems and isn't affected by pre-Clovis at all.
NAGPRA has run into complex issues with ownership being unclear when we've found ancient remains, but that doesn't mean people are rejecting the concept of pre-Clovis. It's a separate set of issues entirely.
I'll mention that many indigenous belief systems do incorporate aspects of "we've always lived here" when that's clearly not what the archaeology says. Most such people accept both sides as belonging to separate things in my experience. It's not all that different from Christians who believe Exodus happened for example. The scientific consensus isn't really relevant to that belief and that's fine.
> Clovis-Americans have certain unique rights based on legal theories that their ancestors were the first human occupants of the land
Please point to these rights and legal theories. Do you just mean NAGPRA?
As far as I know, whatever legal rights any native American people have in the Americas at this point in time are based purely on them being here when Europeans arrived near the start of the 16th century.
Whether they had been the occupants for 400 years or 40,000 years wouldn't make any difference to the treaties that were signed (and generally abrogated).
As of 1995 more than 50% of people who identified as Indigenous preferred the term "American Indian".[0]
It's interesting how people outside of a group can erase that group's identity just by taking away the name that they use to define themselves. Any politically correct American has to say "Native American" or use the even more generic term "Indigenous People" while the majority of the people being referred to understand themselves to be "Indians" or "American Indians". Hundreds of years being known as Indians and having that taken away by scholars and academics. It's a sad final twist on an exceptionally sad story.
What is the correct terminology: American Indian, Indian, Native American, or Native?
All of these terms are acceptable. The consensus, however, is that whenever possible, Native people prefer to be called by their specific tribal name. In the United States, Native American has been widely used but is falling out of favor with some groups, and the terms American Indian or indigenous American are preferred by many Native people.
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This also provides a good overview through a series of personal viewpoints:
I don't get where this "has to" business is coming from. If they want to be called Indians or American Indians, then I'll call them that. There's no need to get wound up.
"From our oral histories, we know that our people have been part of this land since the beginning of time," a leader of the Umatilla tribe wrote in a statement at the time. "We do not believe that our people migrated here from another continent, as the scientists do."
I hesitate to try to engage in this nonsense, but it's worth pointing out that the Kennewick remains were 9k years old. He was all but certain a clovis descendant, just like modern native americans.
This is actually a different claim that one in the comment you're replying to.
Being "the first humans to migrate to the Americans" is quite different from "we didn't migrate from anywhere at all, we've been here forever".
I've never understood human cultures that use oral histories. The oral history of the US from 6 months ago is completely unreliable. Who could possibly put much stock in an oral history of several thousand years ago, and why?
Generally, I'd say that any group of Native Americans (or folks who profit from them either emotionally or financially) wants to be thought of as the 'first' people who ever lived on that piece of land. Perhaps they popped up from the earth like the skeletons in Jason and the Argonauts.
There's a legitimacy angle here that's become super important in the last decade or so. Then there's the argument about 'nobody lived here when my people moved in' that's allowed for some people, not for others.
It isn't like the Sioux or the Navajo have been in their current location all that long. It's all so tiresome.
I still don't understand why the question of originality or whatever is anything but a red herring. Europeans came and nearly wiped out the existing peoples and destroyed their cultures. Are we really going to split hairs and say that's a fine and dandy thing to have done? Because if so you'll have to follow it up with an argument for why that same logic does not apply to a hypothetical future invader of the United States, and good luck with that.
>Europeans came and nearly wiped out the existing peoples
The existing peoples wiped out the existing peoples in many cases.
What this all rotates around is a simplistic (and Victorian) view of 'peoples'. 'Red' = the Americas, 'White' = Europe, 'Black' = Africa, etc.
Truth is, a Navajo is not a Hopi, a Celt is not a Saxon is not a Norman. Most of these current fights are simply wordgames played to achieve political power or to suit some peoples' needs for self-flagellation.
> It isn't like the Sioux or the Navajo have been in their current location all that long. It's all so tiresome.
Are there particular reasons that you use the Sioux or the Navajo in this? Is this a general claim that "no populations stay in a particular location for more than X years", or something more specific?
Various Sioux tribes were pushed west of the Mississippi around 1600-1700 by various wars that took place between natives at the time. It's probably the most well-known pre-contact migration of Native American tribes (at least those that live in US/Canada; the Mexica migration into the Central Mexico Valley is probably even more well-known, as it's a very key part of their own histories).
Neither the Sioux nor the Navajo were on the Trail of Tears, which affected the tribes who lived in the US Southeast, most notably the Cherokee, but also the Muskogee, Seminole, Chickasaw, and Choctaw.
The point is, whatever evidence we find, it's unreasonable to think that evidence we've found is the first evidence that existed, so we have to assume the real arrival was a bit before that. When we had evidence of humans arriving 17,000 years ago, it was reasonable to assume humans really arrived 21,000 years ago. When we have evidence of people arriving 23,000 years ago, you have to assume people really arrived 25,000 years ago.
There may come a point, centuries from now, when our evidence feels comprehensive, at which point the error estimate can shrink. But modern archeology is barely 100 years old and most subject areas are still under-studied, so error estimates need to remain large, for now, especially for the prehistoric era. (Obviously error estimates are much smaller for the historic era, where we have a relative abundance of evidence.)