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#42431 - 02/02/12 05:52 PM Humans in America 40,000 years ago?
Bill Offline
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Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
I just saw Nova on PBS. This one was about a big dig in Colorado where they found a lot of mammoths and mastodons. Most of them were at a great depth and about 100,000 years old. However there was one at lesser depth buried in mud. The mud dated at 40,000 years old. The big excitement about the find was that the bones were mixed with some boulders, which they couldn't explain in that context. They just couldn't figure out how the boulders got into that location, since there was no place handy for them to have come from. So they started casting around and came up with a known fact. If you have a dead elephant (or equivalent) one way to store it until you can get around to eating it is to push it out into a lake and weigh it down with some boulders. People have been known to do this very thing, it is a recognized activity. Then they found one of the bones which looked as if it had cut marks on it, as if it had been butchered with stone tools. This definitely got them excited.

The best guess for the first people in the Americas is about 15,000 years ago. I have seen reports claiming as long as 30,000 years, or maybe a little over. There has never been a claim of 40,000 years. So if this turned out to be true it would be a major upset to current ideas about the peopling of the Americas.

I am going to join the group that has some serious doubts about their findings. But I suppose it could be possible. After all modern humans entered Europe around 40,000 years ago, and Australia possibly even earlier. So there is nothing to have positively prevented them from coming into the Americas at about the same time.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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Of Interest?
#42444 - 02/03/12 05:07 PM Re: Humans in America 40,000 years ago? [Re: Bill]
samwik Online   content
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Registered: 10/10/06
Posts: 1100
Loc: Colorado
Originally Posted By: Bill
I am going to join the group that has some serious doubts about their findings. But I suppose it could be possible. After all modern humans entered Europe around 40,000 years ago, and Australia possibly even earlier. So there is nothing to have positively prevented them from coming into the Americas at about the same time.

Bill Gill



I enjoyed that show also, and feel the same way. It is an exciting idea, and it could be possible that any of a number of groups of some "versions" of either erectus, heidelbergenis, neanderthalensis, or early sapiens made their way to isolated places that were virtual oases in the somewhat intermittent ice-age conditions, such as in high mountain valleys.

http://www.pbs.org/wgbh/nova/earth/ice-age-death-trap.html
Quote:
In the Rocky Mountains, archeologists uncover a unique fossil site packed with astonishingly well-preserved bones of mammoths, mastodons, and other giant extinct beasts. The discovery opens a highly focused window on the vanished world of the Ice Age in North America.
...They dug up green leaves that oxidized, turning black, soon after being uncovered.
===

Since the first part of the show focused on how earthquake-generated liquifaction caused living mammoths to sink into the sediments, I wondered why that didn't also seem to be a likely explanation as to how a clump of articulated bones and boulders could find its way down to a 40 ky old layer of lacustrine sediment (laying directly below a 10 ky old layer of similar sediment where a cache may have been weighted down and stored).

Hopefully they'll be able to date the bones and/or lithic surfaces (lichens, pollens, patina, etc.) fairly soon.

~ smile
_________________________
Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.

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#42449 - 02/04/12 10:03 AM Re: Humans in America 40,000 years ago? [Re: samwik]
Bill Offline
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Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
I hadn't thought of the possibility that they might have been sunk by liquefaction as you suggest. But then I thought some more and realized there might have been a difference between a body sunk in the lake with rocks on it and a living animal standing on a surface. For one thing the body wouldn't have weighed that much more than the water it was sunk in, that was why they had the rocks. And the area in contact with the lake bottom would have been quite a bit larger for a body lying down and a living animal standing up. After all, the prescribed remedy if you are caught in quicksand is to lie down, that spreads your weight over a larger surface and keeps you from sinking more.

So there isn't a quick answer. We will just have to wait for more information. I still somewhat doubt that it was killed by humans 40,000 years ago.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42456 - 02/04/12 07:41 PM Re: Humans in America 40,000 years ago? [Re: Bill]
Ellis Offline
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Registered: 01/07/07
Posts: 1474
Loc: Australia
So there are no actual human remains there? Just the mammoth bones that appear butchered? Would they not have to find some more 'concrete' evidence of human occupation than that? Even the lichen etc. on the bones would only date those particular bones in the layers.

With Mungo Man and the other remains in Australia there were whole skeletons discovered right from the beginning. Likewise with the Flores "hobbit" discoveries. Will they not have to find at least some human bone fragments in order to make the huge leap into the statement- "Humans in America 40,000 years ago"?

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#42458 - 02/04/12 08:22 PM Re: Humans in America 40,000 years ago? [Re: Bill]
Bill S. Offline
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Registered: 08/20/10
Posts: 2914
Loc: Essex, UK
I think there is a long way to go before America can catch up with Australia in this area; but give them points for trying. smile
_________________________
There never was nothing.

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#42459 - 02/04/12 08:59 PM Re: Humans in America 40,000 years ago? [Re: Ellis]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
Originally Posted By: Ellis
Will they not have to find at least some human bone fragments in order to make the huge leap into the statement- "Humans in America 40,000 years ago"?

They don't necessarily have to have actual human skeletons. Just unambiguous evidence that humans were involved. Their finding of what looks like cut marks on one of the bones is a step in that direction, but they still have to verify that they are cut marks, not some kind of accidental scrapes or animal gnaw marks. The other thing they have seen is the boulders they found with the bones. They weren't able to come up with a geological explanation of their presence with the bones. So they might have been placed there to weight down the body for storage in the water. That also would imply human activity. Those 2 things tend to indicate that humans were there when the mammoth died.

Before they can definitively say that it was put there by human activity and that it was 40,000 years ago they have more steps. One thing is to get a good date on the skeleton itself. They took a bone sample and sent it to a lab, but the results were inconclusive. So they don't have definite evidence of a human presence 40,00 years ago. And that is why there is a question mark at the end of the subject line.

Anyway they haven't finished analyzing the find yet. They were rushed for time, they were working ahead of a construction project and only had 50 days for the dig. They wrapped up most of the skeleton, what they hadn't dug out already, and the mud surrounding and under it and carted it off to Denver to finish their studies. That will take time, because they won't be rushed by the deadline they had for excavating it. In Denver they will probably take the mud and bones apart practically grain by grain to see what they can find out about it.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42461 - 02/04/12 10:29 PM Re: Humans in America 40,000 years ago? [Re: Bill]
Ellis Offline
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Registered: 01/07/07
Posts: 1474
Loc: Australia
It is an interesting find and I hope that they are able to find corroborating evidence for the theories being brought forward, but, I think that there is a long way to go before there is more than conjecture to offer.

I, personally, remember the fuss here in Oz when the Mungo Man was discovered. It was a whole skeleton and at the time I was teaching that humans had reached Australia via a land bridge about 5-10, 000 years ago from Indonesia!! The fuss was huge and most of it was very negative and ridiculed the idea. The discovery of more skeletons elsewhere in the area finally proved the case. However there are still many in Oz who still, for various reasons, think that aborigines came here across a land bridge 5,000 years ago.

The claims about the mammoth hunters seem credible, but the tentative nature of the evidence seems to make any firm deductions premature I think.

In an ideal world I guess it would be possible to have enough time to investigate this site properly and the development would wait for the result!

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#42465 - 02/05/12 09:32 AM Re: Humans in America 40,000 years ago? [Re: Ellis]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
I have seen some things about the history of people in Australia, but not as much as you might expect. I suspect that the authorities are still in at least partial denial about how old the remains are. One of the problems with Mungo Man of course is that his presence disagrees with the prevailing theories about the spread of mankind.

Now I expect that mankind did reach Oz from Indonesia, but I don't know that there had to be a land bridge. After all there are plenty of places that early man was found that they probably couldn't have reached on dry land. There must have been some kind of boats developed relatively early. Just when that might have been is very much open to debate but a relatively short water passage would have been available quite early.

By the way, do you know where can I get more information about Mungo Man. What I have seen has basically been a sort of "by the way" thing.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42467 - 02/05/12 09:59 AM Re: Humans in America 40,000 years ago? [Re: Bill]
Bill S. Offline
Megastar

Registered: 08/20/10
Posts: 2914
Loc: Essex, UK
A find like this must be enormously exciting. I have never been involved in anything even approaching this magnitude, but back in my fossil hunting days I made a few interesting discoveries, and these were always greeted with a degree of local fuss. My only truly original contribution was establishing almost 8 ft of Red Crag deposit where only 11 ins had previously been recorded. I can only guess at the feelings that must go with a discovery of international interest.
_________________________
There never was nothing.

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#42468 - 02/05/12 12:51 PM Re: Humans in America 40,000 years ago? [Re: Bill]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
Ok, I hit Google and found some references for Mungo Man. The ones I checked out for some reason seemed to be all Australian references, except Wikipedia. It seems that Oz is where most of the interest is. I guess that's not too surprising. After all a common human reaction to almost anything is "it didn't happen here, so it must not be interesting".

Anyway most of the references that I checked out were fairly impartial, so I got some idea of what is going on. Apparently there are 2 general controversies surrounding Mungo Man.

The first is the age. There are some who claim that he is around 60,000 years old and others who say he is around 40,000 years. Both claim to have good evidence for their claim and that the other side is talking through their hats. I will probably have to go with 40,000 years, but I'm not going to commit to it.

The second is coupled to the first. That is the question of Out of Africa (OOA) and Multiregionalism. I'm going to call this MR. OOA of course says that all modern humans are descendents of a group who migrated out of Africa around 50 to 70 thousand years ago (kya). MR says that all modern humans are descendents of Homo Erectus (HE) that migrated out of Africa around 1.8 million years ago (MYA). The MRs say that all the existing populations evolved from HE in place. To keep them all together so that we wound up with just one species there was a lot of interbreeding between the isolated populations around the world. I personally think OOA is correct. The interbreeding postulated by the MRs would require that our ancestors were committed travelers, constantly running around meeting and breeding with the neighbors, even when the neighbors were cut off from them by mountain ranges, deserts, and oceans. The MRs are jumping on the 60 kya age to claim that it proves they are right, because OOA wouldn't have had time to get to OZ by that time.

One of the sites I found had some good info, but they also had some of the most profound bushwa I have ever seen. So you want to take what you find on the internet with a large grain of salt.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42470 - 02/05/12 05:12 PM Re: Humans in America 40,000 years ago? [Re: Bill]
Ellis Offline
Megastar

Registered: 01/07/07
Posts: 1474
Loc: Australia
Bills-
I am glad to spread the word about Mungo Man and also an even older (perhaps) find of different looking bones at Kowes Creek. The recent DNA testing project around the world suggested a Sri-Lankan origin for present day aboriginals. That would not preclude a voyage through Indonesia to get here of course.

The whole academic area of these discoveries is much mired in controversy and downright mud-slinging unfortunately!

Last Easter my eldest daughter and friends, including an anthropologist, visited Lake Mungo, which is not at all lake-ish, but instead is a desert with strange sheltering cliffs called (I think) lunets and soil and rocks that contain sea shells and fossils. The fact that there was evidence of human occupation, which was also successful, seems to indicate there has been a huge change in environment, as Lake Mungo is many hundreds of kilometres inland.

I can't suggest any scientific sources for you, (I am not a scientist in any shape or form) but there is stuff on the net, and if the scientists involved could get their act together this story may become more widely appreciated!

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#42475 - 02/05/12 08:48 PM Re: Humans in America 40,000 years ago? [Re: Bill]
paul Offline
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Registered: 03/21/06
Posts: 3491
Quote:
They just couldn't figure out how the boulders got into that location, since there was no place handy for them to have come from.


do you think they might have domesticated a few mammoths to carry the boulders to the lake?

or did the 40,000 yo humans carry the boulders there?

Im thinking that the boulders should be all over the place as there was a glacier that passed that way before and as the glacier retreated the boulders were deposited.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#42478 - 02/06/12 08:53 AM Re: Humans in America 40,000 years ago? [Re: paul]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
Originally Posted By: paul
Im thinking that the boulders should be all over the place as there was a glacier that passed that way before and as the glacier retreated the boulders were deposited.

Glaciers were a common source of boulders in unlikely places, but in this case the boulders were buried in clay sediments that apparently were not glacial deposits. They were also apparently the only boulders and they were mixed with the mammoth bones. If the boulders had been deposited by glaciers the glaciers would have messed up the bones. The excavators said that they couldn't think of any good geological explanation for he presence of the boulders. Other investigators may be able to come up with other explanations than having the bones placed by 40 KYA humans, but as far as I know nobody has come up with a good explanation.

And of course I am still holding judgement. The dating of the bones may turn out to be wrong, or some other explanation may come up. I'm certainly not ready to accept that it is correct just because one team thinks it is.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42485 - 02/06/12 06:09 PM Re: Humans in America 40,000 years ago? [Re: Bill]
paul Offline
Megastar

Registered: 03/21/06
Posts: 3491
Quote:
If the boulders had been deposited by glaciers the glaciers would have messed up the bones.


Im thinking that the glacier scooped off the top of the hill or mound and deposited the small boulders as it retreated or advanced.

then after the mud hole was created by the glacier, mammoths and other large heavy animals tried crossing the mud hole getting trapped in the mud in the process.

there were small or baby mammoth bones found along side the larger adult mammoths , these would probably have been a snack for the 40 kyo humans if they were actually weighing them down with boulders.

they probably would not have troubled with smaller baby animals.

there may be a obvious reason that there arent many other boulders found in the area , and that could be that flood waters washed them down stream as the glacier retreated but the boulders in the cup of the mud hole along with its elevation level did not allow the boulders in the mud hole to be removed.

we could find out when the last glacier passed this site and compare that date with the dates of the bones.



_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#42486 - 02/06/12 08:59 PM Re: Humans in America 40,000 years ago? [Re: paul]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
They found a large number of animals in the 100 KYA level. There was only one found at the 40 KYA level. That was the one they thought might be the result of human activity. According to the program the lake was created by glacial action, and held water for a long time. It was slowly filled in by sediments washed in, just as most lakes are filling even now. The thing is that the various animals found there were trapped at various dates, starting with the ones at 100 KYA. The one at 40 KYA seems to have been an isolated case.

As far as the glacier is concerned the last glaciation ended about 12,500 years ago, well after the presumed 40 KYA age of the find. I don't know about local glaciers in Colorado.

It is very unfortunate that they weren't able to continue the dig. It appears that they had barely scratched the surface of what might have been found if they could have gone on longer.

Keep on thinking, maybe between the bunch of us we can come up with some kind of explanation. Of course the most exciting idea would be that the diggers were right, it was done by humans 40 KYA. But as I keep saying, I'm not going to bet on that happening.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42488 - 02/06/12 10:13 PM Re: Humans in America 40,000 years ago? [Re: Bill]
paul Offline
Megastar

Registered: 03/21/06
Posts: 3491
it could be that the reason that so many animals were found in a small area in the mud hole is because the animals struggling to remain above water kept the hole dug out deeper than the rest of the mud hole.

and a 13 ft tall mammoth stretched out trying to grasp his last breath might even be 23 ft tall or taller if you count the distance from his hind feet to his snorkel.

snorkel:an apparatus used for breathing under water.

how deep were the animals found.

how much elevation difference was there between the two levels?

Im not trying to debunk this because I personaly think that humans have walked the earth much longer than what we are led to believe today.

Im only offering my thoughts on this matter.



_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#42490 - 02/07/12 01:11 AM Re: Humans in America 40,000 years ago? [Re: Bill]
Ellis Offline
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Registered: 01/07/07
Posts: 1474
Loc: Australia
I too feel that perhaps the history of humans is much more complicated and ancient that seemed to be accepted until recently. It certainly seems that some human-like peoples co-existed for instance.

About how long ago is it now conventionally presumed that humans reached America? Which is the more popular view-- 15,000 or 30,000? It seems a big gap. Also, would it be more likely to have inhabitants earlier on one side of the country than the other? Are all the early humans the same type anthropologically, or are there differences? There were no Neanderthal-types were there?

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#42495 - 02/07/12 08:47 AM Re: Humans in America 40,000 years ago? [Re: Ellis]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
Originally Posted By: Ellis
I too feel that perhaps the history of humans is much more complicated and ancient that seemed to be accepted until recently. It certainly seems that some human-like peoples co-existed for instance.

What we "know" about human ancestry has been changing for the last 50 years. For a time it was felt that humanity evolved in a linear fashion. The first tool user was Homo Habilis. H. Habilis evolved into Homo Erectus. H. Erectus evolved into Neanderthal, and Neanderthal evolved into Homo Sapiens. Well, that is pretty much gone. It seems that we didn't evolve in one straight line. There have been a lot of species of Homo over the past few million years. If you can find them I can recommend "Extinct Humans" by Ian Tattersall and Jeffrey Schwartz and "The Fossil Trail" by Ian Tattersall. They cover the development of Homo Sapiens as a bush rather than a simple nearly straight line.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42496 - 02/07/12 09:12 AM Re: Humans in America 40,000 years ago? [Re: Ellis]
Bill Offline
Megastar

Registered: 12/30/10
Posts: 1365
Loc: Oklahoma, USA
Originally Posted By: Ellis
About how long ago is it now conventionally presumed that humans reached America? Which is the more popular view-- 15,000 or 30,000? It seems a big gap. Also, would it be more likely to have inhabitants earlier on one side of the country than the other? Are all the early humans the same type anthropologically, or are there differences? There were no Neanderthal-types were there?


Ellis, I decided to split replies to your last post in two. So here is the second one.

The most popular view is that humans first reached America about 15,000 years ago. There have been claims that people got here as early as 30,000 years ago, but they have not been accepted. The 40,000 year claim in the Nova story is still being worked on. There have been no findings of any earlier forms of humans. No Neanderthals, no Denisovans, no Erectus, nothing but us folks.

As far as the spread of humans throughout the Americas, that seems to have been fairly quick. It apparently took at the most a few thousand years for humans to reach the tip of South America. This can happen if a well adapted species invades a new locality. They can expand throughout the area just by an increase in population that causes young people to move on into a neighboring region so they will have room to live. So the inhabited area can grow by a few miles a year, and very large areas can be taken over in a relatively short time. This of course does not imply a very high population density in the occupied territory. Population densities of 1 to 2 people per square mile might be possible in the more desirable locations, and they would be much lower in the more difficult locations.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#42516 - 02/07/12 10:27 PM Re: Humans in America 40,000 years ago? [Re: Bill]
Ellis Offline
Megastar

Registered: 01/07/07
Posts: 1474
Loc: Australia
Bill wrote:
As far as the spread of humans throughout the Americas, that seems to have been fairly quick. It apparently took at the most a few thousand years for humans to reach the tip of South America. This can happen if a well adapted species invades a new locality.

Certainly it can! Just look at the Cane Toads!!!

Forgive my flippant comment!

Thanks for the answers to my other questions. I found them really interesting, especially the idea of parallel existences of the various varieties of humans. They really were quick to spread through to South America.

It is interesting that despite the development of so many varieties of human elsewhere, there is no evidence of their being in the Americas, although there is evidence for a wide variety of other species, in the pre-human eras. I wonder why?

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