Skip to comments.Comet theory false; doesn't explain Ice Age cold snap, Clovis changes, animal extinction
Posted on 05/17/2014 12:06:11 PM PDT by Renfield
Controversy over what sparked the Younger Dryas, a brief return to near glacial conditions at the end of the Ice Age, includes a theory that it was caused by a comet hitting the Earth.
As proof, proponents point to sediments containing deposits they believe could result only from a cosmic impact.
Now a new study disproves that theory, said archaeologist David Meltzer, Southern Methodist University, Dallas. Meltzer is lead author on the study and an expert in the Clovis culture, the peoples who lived in North America at the end of the Ice Age.
Meltzer's research team found that nearly all sediment layers purported to be from the Ice Age at 29 sites in North America and on three other continents are actually either much younger or much older.
Scientists agree that the brief episode at the end of the Ice Age officially known as the Younger Dryas for a flower that flourished at that time sparked widespread cooling of the Earth 12,800 years ago and that this cool period lasted for 1,000 years. But theories about the cause of this abrupt climate change are numerous. They range from changes in ocean circulation patterns caused by glacial meltwater entering the ocean to the cosmic-impact theory.
The cosmic-impact theory is said to be supported by the presence of geological indicators that are extraterrestrial in origin. However a review of the dating of the sediments at the 29 sites reported to have such indicators proves the cosmic-impact theory false, said Meltzer.
Meltzer and his co-authors found that only three of 29 sites commonly referenced to support the cosmic-impact theory actually date to the window of time for the Ice Age.
The findings, "Chronological evidence fails to support claim of an isochronous widespread layer of cosmic impact indicators dated to 12,800 years ago," were reported May 12, 2014, in the Proceedings of the National Academy of Sciences.
Co-authors were Vance T. Holliday and D. Shane Miller, both from the University of Arizona; and Michael D. Cannon, SWCA Environmental Consultants Inc., Salt Lake City, Utah.
"The supposed impact markers are undated or significantly older or younger than 12,800 years ago," report the authors. "Either there were many more impacts than supposed, including one as recently as 5 centuries ago, or, far more likely, these are not extraterrestrial impact markers."
Dating of purported Younger Dryas sites proves unreliable
The Younger Dryas Impact Hypothesis rests heavily on the claim that there is a Younger Dryas boundary layer at 29 sites in the Americas and elsewhere that contains deposits of supposed extraterrestrial origin that date to a 300-year span centered on 12,800 years ago.
The deposits include magnetic grains with iridium, magnetic microspherules, charcoal, soot, carbon spherules, glass-like carbon containing nanodiamonds, and fullerenes with extraterrestrial helium, all said to result from a comet or other cosmic event hitting the Earth.
Meltzer and his colleagues tested that hypothesis by investigating the existing stratigraphic and chronological data sets reported in the published scientific literature and accepted as proof by cosmic-impact proponents, to determine if these markers dated to the onset of the Younger Dryas.
They sorted the 29 sites by the availability of radiometric or numeric ages and then the type of age control, if available, and whether the age control is secure.
The researchers found that three sites lack absolute age control: at Chobot, Alberta, the three Clovis points found lack stratigraphic context, and the majority of other diagnostic artifacts are younger than Clovis by thousands of years; at Morley, Alberta, ridges are assumed without evidence to be chronologically correlated with Ice Age hills 2,600 kilometers away; and at Paw Paw Cove, Maryland, horizontal integrity of the Clovis artifacts found is compromised, according to that site's principal archaeologist.
The remaining 26 sites have radiometric or other potential numeric ages, but only three date to the Younger Dryas boundary layer.
At eight of those sites, the ages are unrelated to the supposed Younger Dryas boundary layer, as for example at Gainey, Michigan, where extensive stratigraphic mixing of artifacts found at the site makes it impossible to know their position to the supposed Younger Dryas boundary layer. Where direct dating did occur, it's sometime after the 16th century A.D.
At Wally's Beach, Alberta, a radiocarbon age of 10,980 purportedly dates extraterrestrial impact markers from sediment in the skull of an extinct horse. In actuality, the date is from an extinct musk ox, and the fossil yielding the supposed impact markers was not dated, nor is there evidence to suggest that the fossils from Wally's Beach are all of the same age or date to the Younger Dryas onset.
At nearly a dozen other sites, the authors report, the chronological results are neither reliable nor valid as a result of significant statistical flaws in the analysis, the omission of ages from the models, and the disregard of statistical uncertainty that accompanies all radiometric dates.
For example, at Lake Cuitzeo, Mexico, Meltzer and his team used the data of previous researchers and applied a fifth-order polynomial regression, but it returned a different equation that put the cosmic-impact markers at a depth well above that which would mark the Younger Dryas onset.
The authors go on to point out that inferences about the ages of supposed Younger Dryas boundary layers are unsupported by replication in more cases than not.
In North America, the Ice Age was marked by the mass extinction of several dozen genera of large mammals, including mammoths, mastodons, American horses, Western camels, two types of deer, ancient bison, giant beaver, giant bears, sabre-toothed cats, giant bears, American cheetahs, and many other animals, as well as plants.
This goes against the consensus, it must be wrong...
So, I guess under modern climatology standards, these renegade scientists would be called Comet Climate Change deniers.
Oh, heaven NO!!!!!
A global climate change event in recent human history both unexplained and unable to be attached to human activities.
OH THE HORROR!!
(the sun can’t possibly have anything to do with it, of course)
Ancient Astronaut Theorists believe......
I always thought the global warming was caused by Fred Flintstone and Barney Rubble and their friends.
“changes in ocean circulation patterns caused by glacial meltwater entering the ocean”
In view of the dramatic meltwater created Washington Scablands, and other rapid release of meltwater like Hudson Bay, I’ll stick with temporary ocean current disruption.
Controversy over what sparked the Younger Dryas, a brief return to near glacial conditions at the end of the Ice Age, includes a theory that it was caused by a comet hitting the Earth.Huh? Correct me if I'm wrong, but that's not in the book I read. Straw Man Alert!
The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
[snip] The following ran in the Feb. 29, 2012, edition of the Washington Post. Anthropol[og]ist David Meltzer provided expertise for this story.
Radical theory of first Americans places Stone Age Europeans in Delmarva 20,000 years ago
March 9, 2012
By Brian Vastag
For quite a while the consensus theory was that this extinction was caused by human hunters.
I used to be quite resistant to this notion, as it just seem unlikely to me that human stone age hunters could exterminate so many animal across an entire continent in just a few centuries.
However, we have good the same thing happened in Australia, New Zealand, Madagascar and other islands. The mega-fauna disappeared within a couple of centuries of humans showing up.
So I'm a somewhat reluctant convert.
Why didn’t the mega fauna of Asia and Africa die out as well? I would have loved to see that huge armadillo cousin Glyptodont with its mace like tail walking near a stream during the last ice age.
The theory, which I don’t find entirely convincing, is that African, and to a lesser extent Asian, megafauna were around when humans evolved and had time to learn to adapt to them.
In the Americas, Oz and elsewhere the animals weren’t adapted to this uniquely effective predator and were wiped out by us.
Just curious, but how much have you actually looked into the distribution of massive accumulations of megafauna remains and other detritus deposited at or near the end of the last glaciation in North America and elsewhere?
In any case, for me, the "hunted to extinction" narrative has a "man made global warming" ring to it.
This is an excellent book. I was convinced by it, and remain convinced. The authors showed the debris impact radiating through the U.S. through the existence of ponds that look like a sunburst....as I recall, as far away as North Carolina.
I hear there are still Rodents Of Unusual Size (ROUS).
The “hunted to extinction” theory is actually one of those neat theories that causes cognitive dissonance in PC-people.
It’s PC because it means Man is Evil. Look at how We wiped out so many wonderful creatures! This is the echo of global warming you hear. (Which does not of itself mean it isn’t true.)
OTOH, it would mean the ancestors of today’s Native Americans are the ones who did the wiping out. Which is obviously very much non-PC. There is immense irony in this, if true, because the extinction of the horse (and other potentially domesticable animals) in the Americas was a major contributor to their inability to effectively resist European invasion.
So I enjoy the Progressive types trying to figure out which implication of the “wiped-out” theory should take precedence on the PC-scale.
There are some problems with this mass extinction. The notion that it was entirely non-human related is made a good deal less likely by the fact that many of these animals had survived other cycles of glaciation and ends of the glaciation. Why did this particular one cause the extinction of so many species?
OTOH, the “wipe them out” theory is made less likely because it’s based on the notion that humans first hit the Americas about 12,000 years ago. There is increasing, though not yet really conclusive, evidence that humans have been around here perhaps twice that long. Which would mean that humans lived alongside the megafauna without wiping them out for 10,000 or 12,000 years.
I also find the sheer mechanics of the wipe-out improbable. How many stone-age hunters would it take to cause an extermination across two entire continents? Seems to me it would take many millions, and there just really isn’t evidence of that massive a population being around.
Americans wiped out the buffalo in less than a decade, but we had breech-loading rifles accurate at hundreds of yards. How long would it have taken with spears or even bows?
OTOH, there is that “coincidence” of similar mass extinctions within a century or two of humans reaching multiple other landmasses.
So I think the theory of wipe out is possible, but not conclusively proven.
Interesting observations but you forgot to address my first point which was actually the main point. The evidence of catastrophe near the end of the last glaciation is global but studiously ignored/suppressed by the scientific community. I daresay you won’t find much in “prestigious” scientific journals. Why is that?
Then why was much of the mega-fauna extinction limited to the Americas?
Here's a classic example of the conflicted PC-person.
Here, the claim is made, "Worldwide, there is no evidence of Indigenous hunter-gatherers systematically hunting nor over-killing megafauna."
This is in blatant conflict with exactly that happening in NZ and Madagascar.
The oceans were much lower then, and most of the evidence of humans from then is probably near the previous seacoast.
IOW, humans then and now tended to hang out at the edge of the water. If you find artifacts, they're likely to be from the ocean bottom.
What is your explanation for this suppression?
Clearly, the Clovis' SUVs are to blame.
Thanks CG. He’s one of those go-to guys when a quote is needed from a purported expert, but anyone who claims as he does that all evidence of pre-Clovis sites has been falsified is a scientist in name only.
Yes, the back of NYC restaurants.
You might point me to where I can study the remaining megafauna in Europe and Asia, excepting the Asian subcontinent where elephants still roam. As far as I can tell, Australia, with the exception of some overly large marsupials, never had much else in the way of megafauna to start with. A quick search indicates there were mammoths/mastodons on the African continent at one time. I didn't look any further to determine when they went missing. NZ and Madagascar???
There are so many anamolies associated with this time period that trying to put the blame on humans seems a PC endeavor at best and unmitigated propoganda at worst. There are indications of potential cosmic origin, along with pole wanderings, massive volcanism, flooding and enormous waves traversing entire continents; you get the idea...
You've been around here long enough that you should have at least become suspicious of the motives of many in the scientific community. Uniformitarianism/gradualism is the name; lying is their game. Goes back to at least the early Catholic Church. The PTB don't like to be discovered in their ignorance/malfeasance and they will apparently do whatever is necessary to protect their turf, egos, government grants, whatever. JMO of course...
There was a comet, unlike any other thus far observed, that impacted in the Southern Ocean and flooded the former abyss where we evolved. Explained in a slide presentation here:
When? Perhaps it caused YD, perhaps it was more recent....
Let’s face it, the Indians did not have repeating rifles like the European invaders of Australia, New Zealand and Madagascar. Also I do not have the impression that the Clovis population was very numerous.
The megafauna of Oz, NZ and Madagascar were not wiped out by European settlers, but respectively by the Aborigines, Maori and Malagasy.
The Aborigines arrived in Oz sometime between 40,000 and 80,000 years ago. They were at a stone-age level and remained there till Euros showed up.
The Maoris arrived in NZ around 1200 to 1300 AD. They were also stone age.
The Malagasy arrive in Madagascar sometime between 500 BC and 500 AD. They came from Indonesia, not the nearby Africa. I don’t know whether they were using metals yet, but they probably were. Indonesia, then as now, was home to a wild variety of cultures and levels of civilization, but there were certainly fairly advanced cultures around. They quite obviously had fairly advanced boat-building capabilities, or they’d never have survived their voyage.
None of these peoples needed guns, or, in the case of at least two of them even metals, to wipe out the native megafauna. Assuming that’s what happened, which it’s pretty clear it did in at least NZ and Madagascar, they being so much more recent.
Extrapolating this to the Americas is, I agree, a big jump due to sheer acreage. But the example of Oz seems to indicate that a continent-sized population of megafauna might indeed be vulnerable to extinction by stone-age human hunters.
All somewhat speculative, but the dates and other history are certainly interesting. The biggest flaw in the “American mega-slaughter” theory, IMO, is the increasing evidence humans were in the Americas for many thousands of years before the extinctions started.
Any such extinction would also seem to imply a rather large human population across North America, the physical evidence for which is darn thin, as you point out. A small band reproducing enough in a relatively short time to create that level of population seems unlikely.
OTOH, the Maoris apparently managed to overpopulate their islands and start fighting over the suddenly scarce resources in just two or three centuries, from just a few canoe-loads at the start. Extrapolating that to the American continent might take just one or two centuries more.
gleeakin, I think what we’ve got here is a “hunted to extinction” crusader. I sent him/her to some links that are pretty compelling re a catastrophic end to the Pleistocene and I’m guessing he/she got a painful whiplash turning away from it. Not only that but evidence of simultaneous megafauna extinctions in other parts of the world besides the Americas which he/she also ignored. I’m also wondering if he/she has read there has been few, if any, human artifacts found dating to within a thousand years or so AFTER the events that took out the megafauna. Indicating of course that whatever snuffed the megafauna likely also snuffed most of the peoples of at least North America. Don’t know about the rest of the world.
Having read the book that Sunken Civ has posted on this thread, I am inclined to think it was something more solid that a comet, or else a very large one, perhaps a broken up asteroid. For example, there is a picture of the bottom of Lake Michigan which appears to have been hit by either 2 or 3 large objects in a row. There is also evidence of some things striking Siberia or Scandinavia.
The early Australians had many tens of thousands of years to kill the mega fauna. They also may have killed off a pre sapiens homonid about 12,000 years ago called Kow swamp people. In the wall of human evolution in the Smithsonian one of the Kow skulls is in the far right lower corner. It is called homo sapien, but after comparing it to Neanderthal and earlier Heidelbergensis skulls, I am of the opinion it had more in common with the Heidelberg skulls. Really, the only basis for calling it sapiens is the 12,000 age. when the Europeans arrived in Australia the Tasmanian Devil and Tiger were still alive, and I believe other large animals that are now extinct had survived the aboriginies. They did not survive firearms. There are still significant killings and species depletion occurring in Madagascar as well.
The descriptions of massive bone yards appear in some of Velikovsky’s writings. I also have a book titled “My Way Was North” in which the author describes a cliff face (I think in Alaska) packed solid with bones being eroded out. Unfortunely it is packed away so I can’t give the more precise information and quote. They were bones of the type appropriate for a 13,000 bc disaster. I could imagine giant tsunamis causing such bone piles.
"The enigma of Kow Swamp is that the skulls are younger than those at Keilor and Willandra Lakes, but appear much more archaic. The people at Kow Swamp had large, long heads with very thick bone, up to 13 mm thick. Their faces were large, wide and projecting, with prominent brow ridges and flat, receding foreheads. From above they show a pronounced inward curvature behind the eye sockets, giving the skull the appearance of a flask. They had enormous teeth and jaws, some even larger than Java Man, Homo erectus (Previously called Pithecanthropus, from the middle Pleistocene of Sangiran."
No doubt some of it at the hands of Man but when accompanied by evidence of catastrophe??? ONLY if one ignores the catastrophe I suppose. Anyhow, here in East Texas we have something similar occurring, after a fashion. Fire ants! Yep, fire ants have been credited with creating havoc amongst critters that nest on, near or under the ground. Larger young critters are even at risk if mama drops her newborn on or near a fire ant hill. Ground nesting birds like quail are nothing but a memory. I miss the night calls of Bobwhites and Whippoorwills.
Truth be told, it's the only thing that comes to mind that COULD explain it. Depositing the bones of millions of disarticulated animals along with splintered trees, volcanic ash, large rocks and sand over hundreds, maybe thousands of miles is tough to overlook but the scientific community has done a yeoman's job of it so far. Gives me a case of the RED A$$!
Parenthetically, and re your other post: From many accounts the Smithsonian has been complicit it hiding and/or losing evidence that doesn't fit the uniformitarian or other "consensus" narrative. Such and august institution guilty of fudging the facts??? Say it ain't so...
Maybe I am behind on news, but I thought they only had a few Denisovan teeth, not an actual skull. Has anyone seen the Smithsonian wall of skulls?
I haven't looked at your posting history so I don't know if you're a hit and run type or not. It is a curiosity to me that some people, when offered compelling data opposing their views, fall off a cliff, or something. You are still around, aren't you???
No matter. SunkenCiv probably spent a good deal of time compiling a somewhat dated(now) but exhaustive FR list on the subject that you might find interesting; or not, HERE.
Let me know if you would like to see additional stuff or if you would just as soon discontinue the conversation.
I took a brief look, but I’ve never been much of a believer in Atlantis and Mu and such. I have a scientific POV, and little interest in what I, to be frank, classify as woo-woo stuff.
I also didn’t want to argue the point with a true believer, since I don’t feel any kind of a need to disprove their existence either. So I got bored and left.
No offense intended, just didn’t see how either of us would profit by continued conversation on the subject.
I realize that wasn’t particularly polite. I should have expressed my lack of interest in continued conversation on the subject. The Web, due to its anonymous nature, has a tendency to encourage less than courteous behavior.
I’ve been away a lot, real life stuff.
No offense taken of course. My expressed sensitivity was more tongue in cheek than anything else, but you probably know that.
...just didnt see how either of us would profit by continued conversation on the subject.
Interesting. You can not or will not be swayed by arguments presenting evidence contrary to your, er, faith??? And you have to admit your opinions on the subject are what you choose to believe as much as anything else. Scientific POV? I dunno. Regardless, I like a good debate and I CAN be swayed with compelling evidence.
Up until about fifteen years ago or so I was what I would classify an agnostic. I probably leaned towards catastrophism but didn't know what to believe and honestly didn't care much one way or the other. Furthermore I couldn't see that it really made much difference. Until I discovered malfeasance by many in the scientific community.
I can't even begin to guess how many hundreds of hours I have spent digging, searching, studying and scratching my head in an effort to find out what was and is going on. Much of that done here on FR with the able assistance of other Freepers or spun off from FR. I even discovered that Darwin himself didn't know what to make of the obvious devastation that apparently occurred during historical times(pick an arbitrary date of, say, less than 20K years ago). It was everywhere he looked, particularly in the Americas. It seems his work was co-opted by his benefactor and mentor Charles Lyell who turned it into the uniformitarian/gradual evolutionary nonsense we see til this day. To what purpose I haven't a clue, but there it is.
Have a good day.
Been off more than on the last few months myself but more a matter of frustration with FR than any real life stuff.
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