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Wed Jul 22, 2020, 03:25 PM

Discovery in Mexican Cave May Drastically Change the Known Timeline of Humans' Arrival ...

Discovery in Mexican Cave May Drastically Change the Known Timeline of Humans’ Arrival to the Americas

Surprisingly old stone points found in a Mexican cave are the latest intriguing discovery among many to raise questions about when humans really arrived in the Americas.

For most of the 20th century archaeologists generally agreed that humans who had crossed the Beringia land bridge from Siberia to North America only ventured further into the continent only when retreating ice sheets opened a migration corridor, about 13,000 years ago. But a few decades ago, researchers began discovering sites across the Americas that were older, pushing back the first Americans’ arrival by a few thousand years. Now, the authors of a new study at Mexico’s Chiquihuite cave suggest that human history in the Americas may be twice that long. Put forth by Ciprian Ardelean, an archaeologist at the Autonomous University of Zacatecas (Mexico), and his colleagues, the new paper suggests people were living in central Mexico at least 26,500 years ago.

Ardelean’s work was published in Nature and paired with another study that presented a broader look at 42 known early human sites across North America from the Bering Strait to Virginia. Data from those sites were used to model a much earlier peopling of the Americas, and help scientists reimagine not only when but how the first people reached and populated the New World. The model features a number of archaeological sites, including Chiquihuite cave, which are intriguing but controversial enough, as experts disagree whether the sites actually evidence human occupation.

Chiquihuite cave is perched high in the Astillero Mountains, 9000 feet above sea level and 3,280 feet higher than the valley below. Excavations there were launched when a 2012 test pit unearthed a few stone artifacts that suggested a human presence dating back to the Last Glacial Maximum between 18,000 and 26,000 years ago. More extensive excavations detailed in the new study were carried out in 2016 and 2017, unearthing some 1,900 stone points or possible tools used for cutting, chopping, scraping, or as weapons.

The artifacts were dated by 46 different radiocarbon samples of adjacent animal bones, charcoal, and sediment samples. To the team, they represent a previously unknown technological tradition of advanced flaking skills. More than 90 percent of the artifacts were of greenish or blackish stone, though those colors are less common locally, suggesting to the authors that they were singled out as desirable. The bulk of the material is from deposits dating to between 13,000 and 16,600 years ago, leading the scientists to hypothesize that the humans may have used the cave for more than 10,000 years.

https://www.smithsonianmag.com/science-nature/when-did-humans-reach-america-mexican-mountain-cave-artifacts-raise-new-questions-180975385/

A stone point from Chiquihuite cave (Ciprian Ardelean)

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Arrow 26 replies Author Time Post
Reply Discovery in Mexican Cave May Drastically Change the Known Timeline of Humans' Arrival ... (Original post)
left-of-center2012 Jul 22 OP
Judi Lynn Jul 22 #1
KY_EnviroGuy Jul 22 #2
stopdiggin Jul 22 #5
Richard D Jul 22 #9
certainot Jul 22 #14
2naSalit Jul 22 #8
GulfCoast66 Jul 22 #10
certainot Jul 22 #15
GulfCoast66 Jul 22 #18
stopdiggin Jul 22 #20
certainot Jul 22 #21
stopdiggin Jul 22 #23
certainot Jul 23 #24
GulfCoast66 Jul 23 #26
stopdiggin Jul 22 #3
Chainfire Jul 22 #4
stopdiggin Jul 22 #6
RainCaster Jul 22 #13
Judi Lynn Jul 22 #7
2naSalit Jul 22 #11
ffr Jul 22 #12
murpheeslaw Jul 22 #16
wnylib Jul 22 #17
left-of-center2012 Jul 22 #19
stopdiggin Jul 22 #22
wnylib Jul 23 #25

Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 03:45 PM

1. Earliest evidence for humans in the Americas


By Paul Rincon
Science editor, BBC News website



CIPRIAN ARDELEAN

One of the stone artefacts found at the cave

Humans settled in the Americas much earlier than previously thought, according to new finds from Mexico.

They suggest people were living there 33,000 years ago, twice the widely accepted age for the earliest settlement of the Americas.

The results are based on work at Chiquihuite Cave, a high-altitude rock shelter in central Mexico.

Archaeologists found thousands of stone tools suggesting the cave was used by people for at least 20,000 years.

Ice age
During the second half of the 20th Century, a consensus emerged among North American archaeologists the Clovis people had been the first to reach the Americas, about 11,500 years ago.

The Clovis were thought to have crossed a land bridge linking Siberia to Alaska during the last ice age.

More:
https://www.bbc.com/news/science-environment-53486868

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 03:51 PM

2. Thanks, LoC, you just beat me to it. Very interesting find.

I was just reading another report on this discovery here:

https://www.bbc.com/news/science-environment-53486868

Adding a little to your posted article......

"This is a unique site, we've never seen anything like it before," Prof Higham, the director of Oxford's Radiocarbon Accelerator Unit, told BBC News. "The stone-tool evidence is very, very compelling."

The team excavated a 3m-deep (10ft) stratigraphic section - a sequence of soil layers arranged in the order they were deposited - and found some 1,900 stone artefacts made over thousands of years. Researchers were able to date bone, charcoal and sediment associated with the stone tools, using two scientific dating techniques. During the period known as the last glacial maximum, 26,000-19,000 years ago, sea levels were low enough for people to cross easily from Siberia to America via the Beringian land bridge. But what about during earlier times?

"Before 26,000 years ago, the latest data suggest that Beringia might have been a rather unattractive place for humans to be. It might well have been boggy and very difficult to traverse," said Prof Higham. "We still think the most likely scenario is for people to have come on a coastal route - hugging a coast - perhaps with some kind of maritime technology, which by that stage people in other parts of the world had certainly developed."

While people seem to have been in the Americas before the last glacial maximum, they were probably thin on the ground. It's only much later, between 14,000 and 15,000 years ago, that populations increase substantially.

It's almost impossible to imagine what human existence would have been like during that time but surely was very brutal and difficult. Would seem to be very animal-like, with no language or conscious thought process as we depend on today.

KY........

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Response to KY_EnviroGuy (Reply #2)

Wed Jul 22, 2020, 04:09 PM

5. Ohhhhh WAIT!

there is absolutely NO foundation for such a statement! Brutal and hard perhaps. No language or conscious thought process? That's just flat out wrong! Talk to your sociologist or anthropologist friends ....

"It's almost impossible to imagine what human existence would have been like during that time but surely was very brutal and difficult. Would seem to be very animal-like, with no language or conscious thought process as we depend on today."

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Response to stopdiggin (Reply #5)

Wed Jul 22, 2020, 05:38 PM

9. Maybe not so brutal

Nice climate, plentiful food. Enough hunting skills to get food and protection.

I read a long time ago that hunter/gathers needed a grand total of 4 hours of hard work a day to thrive.

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Response to Richard D (Reply #9)

Wed Jul 22, 2020, 06:24 PM

14. there was a lot less sex on the wrong brain too- less greed and authoritarianism

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Response to KY_EnviroGuy (Reply #2)

Wed Jul 22, 2020, 05:37 PM

8. ...

Check this book:

1491. Charles C. Mann

https://en.wikipedia.org/wiki/1491:_New_Revelations_of_the_Americas_Before_Columbus
An update to what was thought in the 20th Century.


Humans developed beyond what you think long before you might imagine. Just sayin'.

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Response to KY_EnviroGuy (Reply #2)

Wed Jul 22, 2020, 05:44 PM

10. I respectfully disagree.

Yeah, life would have been tough living in a world surrounded by mega-fauna, much of which had us on the menu.

But these people were Homo sapiens They were us. Just as intelligent. Same emotions. Certainly had languages. There is nothing suggesting we have evolved much in the last 20k years.

Look at the Iceman found frozen in the alps. He had amazingly sophisticated tools and gear for the period. It surprised even the researchers. I think he died around 8,000 years ago. Maybe further back.

Have a nice evening.

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Response to GulfCoast66 (Reply #10)

Wed Jul 22, 2020, 06:29 PM

15. but we have much better weaponry now and with a lot more sex on the wrong brain we have

more greed and certainty deficit disorder (fear, authoritarianism, bigotry, patriarchy, misogyny, fear of nature). luckily there's some democracy going around, but not enough yet to save us from suicide by global warming.

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Response to certainot (Reply #15)

Wed Jul 22, 2020, 07:15 PM

18. Wow!

I have no doubt the early humans were just as violent and prone to bad decisions than we are now.

And remember, evidence points to early Americans were responsible for killing off our mega-fauna.

Humans have never been saints.

The Ice Man I mentioned in my first post? He died a violent death killed by an arrow and having his brain bashed in.

People are people.

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Response to GulfCoast66 (Reply #18)

Wed Jul 22, 2020, 10:38 PM

20. thank you

Homo sapiens has been homo sapiens for quite a while -- that's just fact. To imagine those that preceded us as either mindless club wielding brutes -- or on the other hand the unsullied "noble savage" are both hopelessly shallow (and misinformed) caricatures.

"Civilization" on the other hand (and all the changes encompassed there) -- has been undergoing some fairly rapid transformations.

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Response to stopdiggin (Reply #20)

Wed Jul 22, 2020, 10:50 PM

21. humans went from about 50-50 right and left handed like chimps to 90%

right handed 100,000 years ago.

sex on the wrong brain theory suggests it makes a difference which side of the brain we associated sex with - which hand.

right hand to left brain increased greed, fear, and the need for certainty (absolutism, bigotry, patriarchy, suspicion, lack of empathy, etc) , and that was a an advantage in times of conflict as populations increased. in the last few thousand years as populations and 'civilizations' grew they began to delay the age of reproduction sex on the wrong brain got worse. (columbus meets the natives)

trump was a frustrated dipshit who could not get a date and had a prince's privacy and opportunity to develop sowb.

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Response to certainot (Reply #21)

Wed Jul 22, 2020, 11:30 PM

23. I don't find this at all compelling

and I won't be spending any time trying to "educate" myself.

You are intent on mashing together dates as disparate as 100,000 years distant -- to 20,000BP (as discussed in the article) -- and Columbus meets natives -- with a theory that is -- of little or no value (to put it in the kindest of terms).

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Response to stopdiggin (Reply #23)

Thu Jul 23, 2020, 02:05 AM

24. right handed dominance is 'credited' to tool-making or language but sowb goes back to our earliest

ancestors, long before those factors.

reproduction is right up there with hunger and thirst. you saying it wouldn't effect our evolution?

and the divided brain goes back farther than that, including to birds, for instance. the idea the it wouldn't matter what hand we masturbated with wouldn't make a difference is ridiculous. back then life was shorter and reproduction started earlier.

our societies have formed around the increased irrational need for certainty - caused by associating impatient satisfaction-demanding reproductive impulses with brain functions that need patience and objectivity. logic is satisfied with finality, conclusion - certainty. authoritarianism is sometimes measured with the uncertainty avoidance index (UAI). authoritarians use order, simplification, absolutism to simplify the world/nature and help them judge the world in black and white, good and evil, etc. we invented religion to ease our fear of uncertainty and help us manufacture certainty.

the right brain is generally more engaged in emotion, sex, orgasm - why associate sex with the side of the brain that has more to do with detail, math, logic?

it was a slight advantage over millions of years that got much worse in the last few thousand years as humans necessarily began to delay the age of reproduction. at some point authoritarian leadership may have recognized the best way to create an army was with sexual repression - to keep young men frustrated and jacking off - by default with the wrong hand. the koran left the secret of authoritarian power in, mandating that "man can only have sex with his wife and that which the right hand possesses..."

populations in different environments selected for particular sowb symptoms which eventually manifested as inherited susceptibilities for particular sowb symptoms. so descendants from european "old world" civilizations may be more susceptible than those from the 'new world', and it looks like trump got bad genes for a modern democracy, but perhaps not for a monarchy.

is the disparity in sow a source of bigotry, racism, sexism?

authoritarian societies have a built in defense - as joycelyn elders found out, even mentioning the word 'masturbation' is out of bounds.

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Response to stopdiggin (Reply #20)

Thu Jul 23, 2020, 09:35 AM

26. Right. And 'civilization started long ago.

As soon as we learned to cultivate crops and domesticated animals.

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 04:00 PM

3. thanks. quite interesting

although I think the evidence here is a bit tentative (we'll see where peer review goes here)

But the cumulative evidence (even when tentative) would seem to be clearly pushing the dates backward from the previously accepted 14-16,000 years for human occupation.

(and part of the problem here is that, while exciting and very popular, anthropology is infused with more than it's fair share of wingnuts and crackpots -- which leads the rest of the profession towards a fallback reliance on caution and skepticism.)
--------- --- ---------

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 04:08 PM

4. That is very interesting

When I was a kid, it was estimated that this hemisphere had been occupied for ten thousand years. I didn't realize that I was that old. You have to wonder how many times the cave had to be renovated with 10,000 years of occupancy?

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Response to Chainfire (Reply #4)

Wed Jul 22, 2020, 04:11 PM

6. that couch needs to be shifted

many, many times!
----- -- -----

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Response to Chainfire (Reply #4)

Wed Jul 22, 2020, 05:59 PM

13. It's only with the discovery of HGTV that reno became a thing

Before that, men could get by with only 4 hours of work each day.

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 04:26 PM

7. Surprise cave discoveries may double the time people lived in the Americas

Barren and remote, Chiquihuite Cave in Mexico seemed an unlikely place for anyone to live. But stone objects recovered from deep inside the cave may tell another story.


BY KRISTIN ROMEY
PUBLISHED JULY 22, 2020

WHEN RESEARCHERS FIRST arrived at a cave high in the desert mountains of north-central Mexico, they hoped to learn what the environment was like there thousands of years ago. But the unexpected discovery of what they believe is an ancient projectile point led to a decade-long excavation that could rewrite the history of the Americas.

According to a paper published today in the journal Nature, the site, known as Chiquihuite Cave, may contain evidence of human occupation that places people in North America around 30,000 years ago—roughly twice as early as most current estimates for when the first humans arrived on the continent.

The question of when people first arrived in the Americas has been debated for more than a century. For much of that time the reigning theory put the arrival around 13,500 years ago. But archaeologists are now exploring sites that keep pushing the date farther back, including some who have reported finding signs of human presence beyond 30,000 years ago. The evidence supporting those claims is hotly contested, and this latest discovery is already stirring more controversy.

. . .


New find suggests humans in North America pre-date the last great ice age.

The earth’s Last Glacial Maximum ended 19,000 years ago. During this time, vast ice sheets covered land and sea level was about 400 feet lower than today’s. Previous models for explaining the arrival of Homo sapiens to North America supposed that migration into the continent came after glaciers retreated. But a new discovery of stone tools in a Mexican cave indicate human arrival possibly occuring thousands of years earlier.

More:
https://www.nationalgeographic.com/history/2020/07/surprise-chiquihuite-cave-discovery-mexico-double-peopling-americas/

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Response to Judi Lynn (Reply #7)

Wed Jul 22, 2020, 05:53 PM

11. Well the Nat Geo article has

opinions from other researchers and they aren't even close to convinced about the dating. The stone comes from outside the cave which is of interest but the possible artifact doesn't sound real promising. If they find human or animal DNA in the small crevices of the stone, then that would indicate, with confidence, that it was a tool.

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 05:54 PM

12. "leading the scientists to HYPOTHESIZE that..." Not theorize.

This is one of the first written articles that gets the terminology correct. We hypothesize about what we don't know and haven't proven mostly, but we draw conclusions from known proven theory. We do not theorize, we hypothesize about what we haven't proven. We theorize if it's based on something already proven or based on scientific laws or theory.

That was beautifully written. I was captivated by every word.

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 06:56 PM

16. Where was the coast line?

When sea level was 400’ lower how much early early evidence is covered with water and silt waiting for discovery 200 yards off shore?

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Response to left-of-center2012 (Original post)

Wed Jul 22, 2020, 06:56 PM

17. One problem in establishing

when people arrived in the Americas has been the assumption that land travel had to be the only means.

Several years ago I visited the Arch/Anthro institute at Mercyhurst University in Erie, PA. The director at that time was James Adovasio, the archeologist who led the excavation of Meadowcroft Rockshelter north of Pittsburgh, where dates went back to 14,000 years ago and earlier.

I talked with Dr. Adovasio's assistants about arrival timing and how it happened. They discussed not just a water route, but a maritime culture extending from eastern Asia to western North America, which would look like an upside down horseshoe shape on a map.

I was skeptical then, but not any more. We know now that modern humans have been in Australia for over 50,000 years. Even accounting for exposed land during glaciation, there are still about 70 miles of open water they would have crossed to reach Australia. They knew how to "sail" or jyst drift on rafts that long ago.

DNA studies of human migrations out of Africa show that some groups of people hugged coastlines of India and southeastern Asia for millennia during expansion into Asia. Homo sapiens adapted to marine cultures very early. Water became roadways, not obstacles.

There are numerous islands off the coast of northeastern Asia. There are the Aleutian Islands extending out from southern Alaska almost to Asia. A maritime culture could live off of fish and marine and land animals. They could use wood and stone from the islands for tool making, as well as animal bones, skin, and sinew.

Beringia did not emerge overnight. Centuries of glacial expansion caused land to appear gradually, connecting some islands to mainland Asia and to other islands, or narrowing the distance. As less Arctic waters seeped into the Pacific while Beringia was developing, the climate was a little less severe.

Following Asian islands to the Aleutians and down the Pacific coast of North America, a marine culture could have skirted the glaciers and the bogs of Beringia. Once on the Pacific coast of North America, there were options to settle North American islands (now submerged), continue down the coast to even warmer climates, or take water routes (rivers, lakes) inland into North America, south of the glaciers.

Inland, the regions on the southern borders of the glaciers were rich with seasonal meltwater and the plants that grew there as well as animals attracted to watering holes. People could expand inland to the east in North America fairly quickly.

Or, follow the western coast of North America to Central and South America.

Early dates for people in the Americas are not confined to the limits in time of Beringia and glaciers. They can be as old as the evidence from scientific dating methods indicate. Follow the evidence and then figure out what happened instead of assuming what happened and then discounting evidence that doesn't support the assumptions.

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Response to wnylib (Reply #17)

Wed Jul 22, 2020, 08:37 PM

19. "a water route"

Yep. Read about one some years ago, where they followed the west coast south.

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Response to wnylib (Reply #17)

Wed Jul 22, 2020, 11:07 PM

22. I think the archeological community

is currently pretty open to new ideas about dispersal and inhabitation -- if it tracks with the evidence as it is known. (the old Paleo culture theory -- which was maybe a bit entrenched for a time -- is now far in the distance -- at least a generation past.)

And currently -- DNA study and modeling of dispersal, migration, integration and displacement -- stands ready to inject an entirely new layer of evidence to the discipline. Exciting times.

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Response to stopdiggin (Reply #22)

Thu Jul 23, 2020, 05:15 AM

25. Yes, archaeologists are more willing

to let go of the old Clovis theory than they were a generation ago. Dr. Adovasio was so frustrated with their rigid refusal to accept his findings and the lengths they went to in trying to discount his work that he referred to them as the "Clovis Mafia."

The path across Beringia and later down an ice-free corridor into North America never did sound right to me. But one reason why it was held to so strongly by archaeologists in the past is that it offered a science based explanation for the peopling of the Americas instead of popular nonsense about lost tribes of Israel, or survivors from Atlantis being the source of the Native populations of America.

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