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Ancient Chesapeake site challenges timeline of humans in the Americas (washingtonpost.com)
62 points by pge 7 months ago | hide | past | favorite | 50 comments



Linguistic evidence of the same timeline.

https://languagelog.ldc.upenn.edu/nll/?p=64074

The controversy claimed is entirely overblown. Longer timelines for migration have been discussed widely for quite a while.

I completely understand not wanting to bother with peer review but generally your peers want a good result to be published.


Yeah I think the scientist just has a chip on his shoulder or the journalist wanted to sell a more interesting story. I think the real controversy boils down to this:

> But the geological record is like reading the CliffsNotes version of a book, and he was frustrated by an “unconformity” in the sediment layers where thousands of years were missing, like someone had ripped out those chapters.

It’s an island and they’re not the most reliable for dating sediment layers - they’re not exactly closed systems.

I haven’t read his book but I can totally see a case for skepticism over the precise dating. It’s a common trick/error to play fast and loose with carbon dating calibration standards and sample collection to get better numbers. It’s hard to get right in the best of times and the results have to be taken in context.


> The controversy claimed is entirely overblown. Longer timelines for migration have been discussed widely for quite a while.

Are you saying that: Effective, significant resistance to pre-Clovis theories wasn't a thing in the latter 20th cent ?


The current year is 2024. There are phds out there who were born after 2000.


Sure but a mindset that is dominant enough to influence the direction of research can reasonably be expected to persist - even though there's turnover in the field.


If you entered academia in 2000 when this became the newly accepted wisdom you'd be around 50 now.

Face it you're just old and still think 2000 was four years ago.


> Face it you're just old

Again, sure. That's how I know professional mindsets can age a lot slower than people.

> you ... think 2000 was four years ago.

Hardly. Want time to go slow? Care for 5 kids + disabled spouse on your own. It makes regular years seem like mindset years.


There is an elephant in the room in my opinion on the matter of a migration to N. America across the atlantic, however I have not read a definitive evaluation of this piece of evidence.

There exists, mostly in the northern tribes (Ojibwa 27%, Sioux 15%) mtDNA of the X type. As I understand it the other highest group in the world is the Druze population in the Levant. (27%) What it all means is above my pay grade.

Background https://en.wikipedia.org/wiki/Haplogroup_X_(mtDNA)



A bigger issue may be the site’s rapid erosion. Most of the artifacts were found after they’d fallen out of the bluff, which means their place in the geologic timeline is obscured. Nine artifacts were found in place, and only three were able to be dated using charcoal flecks found next to them.

Hat's off to him for publishing it. There are currently serious problems with the peer reviewed publishing process, starting with the fact that it was born in an era when the scientific world was smaller and people reviewing your work may have known you or someone vouching for you and this is generally no longer true.

But we do rely heavily on where in a sediment layer a thing was found to try to date it, so with that piece missing for most items, arguing about the defects of the power review process is kind of moot. He should probably work at addressing this issue and maybe that's the piece he doesn't really want to wrestle to the ground to begin with in the peer review process.


I think there's also an argument to be made that in fields where agreement with authority might hold more sway, there needs to be a public publishing outlet for "inconvenient" results.

In chemistry, either the proposed path works or it doesn't.

In squishier sciences (econ? archaeology? history? long-term fields like dietary and environmental sciences?), there's less ability for things that fly in the face of conventional wisdom to be provably correct solely on their content.

Consequently, there's more ability to suppress them. Or at least apathetically ignore and not circulate them.

And, to the point here, there's a lot more rocks lobbed at you when you're challenging the status quo that careers have been built on, versus following or supporting it.

Nobody wants to be wrong about something they've staked decades on.


> hunting big animals like mammoths and giant sloths, driving them into extinction as they went.

Interesting read, and above quote shouldn’t distract from it, but I thought that theory was abandoned, or at least certainly not considered so likely that it would be presumed by default anymore.


I've always heard that megafauna disappearances coincide with human appearance; what other theories are beating that out?


As a counter point, African megafauna did not go extinct during the same time period, despite the constant presence of humans. African climate was also more stable during the time. On the other hand African megafauna would have co-evolved with humans, so they may have been adapted. But probably there was no single cause.


There’s enough food in africa where even today going out to hunt an elephant demands a brush gun and a white superiority complex, and is not how most hunt the bush.


It might have been driven by the same environmental changes that allowed humans to settle in a specific region in the first place. But in the end I guess it's several things coming together, like with most catastrophic events.


Climate change. The humans were there in part because of environmental change in the first place. Large deposits of dead animals all killed at the same time with no evidence of hunting or butchery makes mass die offs likely. Humans may have participated, but were likely only one among other factors.


These megafauna survived dozens of ice ages but not the one that had humans

https://www.smithsonianmag.com/science-nature/what-happened-...


True enough.

and yet you've linked to an article that goes into detail about work that

    may be close to a deathblow for the hypothesis. 
"the hypothesis" being

    First proposed in 1966 by paleontologist Paul Martin, this “overkill hypothesis” stated that the arrival of modern humans in each new part of the world brought with it the extinction of all those huge animals, whether through hunting them or outcompeting them. 
So, we're back to correlation but not at all certain causation. By your link at the very least.

The Smithsonian Magazine here is being wishy washy and doing the "good points on both sides" thing .. it at least admits that the world has moved on from accepting Martins 1966 hypothesis at face value and that new work is continuing to reveal new insights.


"Humans hunting megafaune to extinction" is a subset of "megafauna disappearances coincide with human appearance" (See: Venn Diagram).

The second does not imply the first, correlation is not causation.

> what other theories are beating that out?

See: almost any scholarly discussion on megafauna disappearences in (say) Australasia or elsewhee of the past few decades.


https://www.smithsonianmag.com/science-nature/what-happened-...

TL;DR: no theories are beating it out human overkill. Megafauna need to show a mass extinction sans humans and that evidence is lacking. These animals survived a couple dozen ice ages but the final one ends their existence when humans arrived. We would want more hunting and butchering evidence and Africa kept much of its megafauna. So there are unanswered questions but overkill is still largely yhe leading theory


See: https://news.ycombinator.com/item?id=40426463

Your article is a PopSci "both sides" summary that reinforces the notion of correlation and not causation.


What was the sea level at 20K years ago?

I was wondering whether more exposed land would have made much difference to migration routes?

The DNA record doesn't show any migrations across the north or south Atlantic Ocean, correct? Is there any evidence of humans using routes other than the Bering Strait?


Quite low. In fact around 20,000 years ago during the last glacial maximum (LGM), sea level was around 130 meters lower than current day.

Referenced from https://www.e-education.psu.edu/earth107/node/1496


Is the controversy that the "Clovis" (who are the genetic ancestors of Native American or indigenous) were not actually the first people in North America?

Did the Clovis conquer or wipe out the pre-Clovis people?


We know that the people behind the Clovis material culture weren't the first people in the Americas. It took decades of work by academics like Tom Dillehay, but that's been the status quo since the 90s.

We don't know what happened to the preclovis groups. It's likely they were absorbed/became ancestral to later groups like those behind Clovis culture rather than erased, but the evidence is too scarce to say anything definitive.


> Is the controversy that the "Clovis" (who are the genetic ancestors of Native American or indigenous) were not actually the first people in North America?

My understanding is that Clovis-first has been considered rejected by the anthropology community since the 90s. Yet it's somehow treated as the dominant viewpoint being challenged in every single popular anthropology article even now in 2024.

Also, Clovis isn't necessarily the genetic ancestor of modern Native Americans. Evidence of Clovis culture is predominantly based on tool type, and material that can infer genetic relationships is almost entirely lacking.


The sequencing of Anzick-1 provides pretty clear (if imperfect) evidence that some Clovis populations were ancestral to a lot of modern indigenous Americans, since it's basal to most South American groups.


Is using the term "indigenous" in reference to people living in the Americas before Columbus an implicit repudiation of the "Out of Africa" theory?

https://en.wikipedia.org/wiki/Recent_African_origin_of_moder...


No, it's just a widely accepted term for descendents of the people who inhabited the Americas before European colonization. Their (long ago) ancestors are also our long ago ancestors in Africa.

The reason "indigenous" is used is mainly historical, but there aren't any better modern terms. "American Indian" is largely a US term and one a lot of people don't like. "Native American" has similar issues. "First nations" is mainly used by Canadians and doesn't encompass all the groups being discussed. "Indian" works, but "indigenous" has a lot less semantic baggage.


Heh. I like “Clovis police.”

That’s a problem in any community; gatekeepers.

But, at the same time, as Sagan mentioned, extraordinary claims require extraordinary evidence. A lot of completely batshit stuff pops up, all the time.


Sure, extraordinary claims require extraordinary evidence. But this claim is not so extraordinary. It's just against what was (at one time) the common wisdom.

Extraordinary claims would be that humans were in this location far earlier than previous evidence suggested and they had mastered flight or were doing calculus or something.


I know that. There has been a pretty steady drumbeat of evidence of pre-Clovis stuff for many years.

I apologize for appearing to dis the claim. That was not my intent. I was simply stating the issues we face in these types of things, with gatekeepers and crazies.

I actually support this guy. I think he's probably correct.


A series of ordinary evidences can collectively make an extraordinary claim more probable than its negation.


Oh my God. I'm back. I'm home. All the time, it was... We finally really did it. You Maniacs! You blew it up! Ah, damn you! God damn you all to hell!

https://www.pinterest.com/pin/animated-gifs--365917538457473...


I read "ancient cheapskate site" and was imagining a price comparison website from the early 2000s.


“Ancient Chesapeake site forces paleontologists to admit they were wrong after denying clear evidence of much older occupation across the Americas for decades.”

Fixed the headline boss!


No paleontologists involved here. The article also isn't about forcing people to admit they're wrong, because preclovis is already widely accepted. It's about the tension in meeting the extremely high standard of evidence for that claim against the reality of the site's fragility and destruction.


Again????

American archaeologists and their desire for fame... Dig up a hole, find the stone tools that evidence human occupation, draw the stratigraphy, do radiocarbon dating, publish in a reputed journal (not your MySpace), rinse and repeat...


> (...) archaeologists (...) Dig up a hole, find the stone tools that evidence human occupation, draw the stratigraphy, do radiocarbon dating, publish in a reputed journal

I mean what else did you expect archaeologists to do?


Running from boulders. Punching Nazis.


[flagged]


Indiana Jokes


You would be surprised. For one, they can't be bothered to dig anymore. Many of them are mesmerised by aDNA, cropolites (or traces of them in lakes), and whether paleoindians were feminists or gay...


Archaeologists don't dig holes for fun. Excavations are just one set of tools in a larger investigative toolkit. If you can do the research without the hassle and expense of a trench, why shouldn't you?


I can't tell if OP commenter is complaining archaeologists dig too many holes or not enough.


Narrative consistency isn't necessary for trolls to get the attention they desire. Quite to the contrary.


Knowing many professional archaeologists, I have no idea what you're talking about.


He read something on Twitter and now he’s incensed.


They're mocking doing archeology with an agenda FYI


It's a strawman fallacy, not mockery. I never heard of archaeologists doing any of what they are accused of here.




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