Part 2: Prehistoric Human Migrations, Language Groups, Jim Thorpe
Part 1 has it's own life and is far from complete.
However, there is a second path to follow and worth it's own investigation.
Interestingly enough, the geologic "black mat" that covers the last era of the North American megafauna and any remaining artifacts of the Clovis People. It is, also interesting in that both came to an end suddenly. Like a light switch turning off at the time just prior to the black mat.
Many "credit" the the Clovis People for hunting the North American megafauna to extinction, yet they both vanished at the same time.
Question marks run through the mind. Why would the Clovis People vanish at the same time as the megafauna when obviously plenty of other game existed in the region at the same time?
Also curiously, the timing of all this correlates with a sudden return to Ice Age conditions known as the Younger Dryas.
Why would a return to ice age conditions seem to correlate to the elimination of both the Clovis People and megafauna when each had survived worse ice age conditions in the past?
Theories have developed which point to a catastrophic event happening in North America resulting in conditions producing climate changes resulting in the Younger Dryas. Conditions across the globe point to something happening here in North America.
There are archeological findings which point towards people living in the Americas 20 - 30K years ago. Were these people around during this event causing the Younger Dryas?
Did any survive this event? If so, were they assimilated? Or are they lost to history?
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A few contributors headed down this path is Part 1. Now it's time to head down this path and let each discussion take it's own direction.
What are your thoughts?
Marking a spot and I'll be back to join the conservation.
Thank you Kavika.
Spot reserved.
Here's some spots for ya Kav.
Oh no, I've been spotted.
LOL
These days even the most reserved of archaeological institutions acknowledge evidence of human life in the Americas between 20K to 30K years ago.
Even the Smithsonian, gives acknowledgement. Here is an article from the reserved institution:
Humans May Have Arrived in North America 10,000 Years Earlier Than We Thought
A 24,000-year-old horse jawbone is helping rewrite our understanding of human habitation on the continent
The horse mandible marked by traces of stone tools, which might prove humans came to North American 10,000 years earlier than previously believed. (Lauriane Bourgeon/University of Montreal
January 31, 2017
The caves were hidden high above the Yukon’s Bluefish River, at the base of a limestone ridge in the middle of a sprawling wilderness. When a helicopter reconnaissance of the river spotted the caves in 1975 , it may well have been thousands of years since the last humans entered them—or so hoped archaeologist Jacques Cinq-Mars.
Between 1977 and 1987, Cinq-Mars led a team into the remote wilderness, battling clouds of mosquitoes and cold weather to excavate the layers of sediment and bones. What he found was a game-changer.
At the time, the prevailing theory was that the Clovis were the earliest human inhabitants of the Americas, with sites across North and Central America containing their iconic spearheads . As early as the 16th century , Europeans proposed that a land bridge between Asia and North America might have provided the route for early human migration; by the 1940s scientists were actively looking for and finding evidence for the bridge’s existence. And in the 1930s, spear points discovered near Clovis, New Mexico were discovered to match the artifacts found in Beringia , convincing people that the Clovis came first, approximately 13,000 years ago .
But when Cinq-Mars brought the fragments found at the Bluefish Caves back to the laboratory, he came to an incredible conclusion: humans had actually occupied North America as early as 24,000 years ago .
Naturally, the scientific community was skeptical. Other archaeologists raised a number of doubts about the bone samples. Anything in the environment can leave marks on artifacts: freeze-thaw cycle can snap bones, wolves and other carnivores chew on them, rocks fall on them from the ceiling of the cave. And it just didn’t fit into the Clovis hypothesis.
“For at least 70 years, everybody was stuck on ‘Clovis first,’” said anthropologist Dennis Stanford with the Smithsonian’s National Museum of Natural History. “Anybody that came up with another kind of site was shouted down or disproved.”
The discord surrounding Cinq-Mars’ discovery resulted in a portion of the collection never being thoroughly analyzed, and researchers eventually lost interest. But now, 40 years after Cinq-Mars’ initial discovery, it seems the archaeologist has been vindicated.
Canadian scientists Lauriane Bourgeon and Ariane Burke , assisted by University of Oxford professor Thomas Higham, conducted a two-year re-analysis of the bones found in the Bluefish Caves, poring over 36,000 bone fragments held in a collection at the Canadian Museum of History and studying fragments that hadn’t previously been taphonomically classified. After doing a thorough classification of the markings on the bones as made by natural forces or humans, they conducted radiocarbon dating of those they deemed to have been marked by humans. The earliest bone to show distinct human-made marks—a horse jaw, sawed by a stone tool that indicates the hunter was attempting to remove the tongue —dates to 24,000 years ago.
The horse mandible was the most exciting find for Bourgeon. It bears multiple straight cuts, very similar to those made by stone tools and distinct in shape from marks made by carnivore teeth and natural abrasion. Additionally, the cuts match the patterns that would be created from butchering the horse. Altogether, Bourgeon says, the marks on the bone fulfill multiple criteria that would classify them as having a cultural origin, whereas it would be hard to explain their existence by natural processes.
“It was fairly exhausting,” said Bourgeon of their investigation in an interview conducted in French. “But I was really passionate about the project. When you see those traces of cuts on the bones, and know that horse is believed to have disappeared 14,000 years ago, that means we can guess humans were here before. It was a huge discovery.”
Bourgeon and Burke’s research provides new evidence for a more recent hypothesis that aims at overturning the old ‘Clovis first’ assumption. Known as the Beringia standstill hypothesis, it states that there was a pause in human migration from Asia to North America between 30,000 and 15,000 years ago due to the frigid climate. The standstill coincides with the last glacial maximum (about 26,000 years ago to 19,000 years ago), the most recent period in Earth’s history when the ice sheets were at their furthest southward extension (think glaciers down to New York City ).
If the evidence bears out, it would also mean that humans came to North America a whole lot earlier than previously believed: 10,000 years earlier. Humans were living in the Siberian Arctic prior to the last glacial maximum, when the climate was milder and hunting options were abundant. Archaeologists have found evidence of human habitation in western Beringia (the landmass now beneath the Bering Strait) from 32,000 years ago , near the Yana River. But as the climate grew colder, humans would have been forced to migrate in search of food and shelter.
“Think of Arctic deserts as sets of lungs,” writes archaeologist Brian Fagan . “In warmer and moister times they breathe in people and animals, then they exhale them when aridity and cold intensify. This is what happened in Siberia during the last glacial maximum”—and what presumably chased humans out and likely decreased the size of their population .
Luckily for the early humans, the Beringia land bridge had a relatively mild climate despite its high latitude, thanks to the North Pacific Ocean circulation patterns bringing humidity to the region. That humidity allowed for more plant growth, in turn giving humans the fuel to build fires. And with the new evidence from the Bluefish Caves bones, researchers can see that humans did migrate sometime during the last glacial maximum, and were likely trapped on the Beringia land bridge due to the presence of glaciers all around them. In other words, they were stuck at a standstill.
Of course, not all archaeologists are completely convinced by the Bluefish Caves research. “I’ve seen pictures of the new bone they found, and it does look like it could possibly be human [markings],” said Stanford, who was not involved in the study. “But they didn’t leave much of an echo of a record if they were there. If there was a human in [the caves], why haven’t they been able to find any real artifacts? What technology did they have and why didn’t they leave anything?”
Bourgeon agrees that she’d like to do far more research on the region. Based on their discovery, she’s convinced they’ll find more equally ancient sites with evidence of human habitation. She’s never been to the Bluefish Caves and would like to visit that site, and look for others in the Yukon. But between the financing and logistics of such an expedition, it’s no easy undertaking.
“You can only work in the summertime, between June and August,” Bourgeon said. “It’s a very vast, sparsely populated region, an environment that’s hostile.” But, she added, the standstill hypothesis is starting to be more widely accepted, meaning more scientists will want to develop projects in the region. And as they do, she hopes they’ll find more pieces in the puzzle of human colonization of North America.
Editor’s note, February 1, 2017: This article originally missplaced the Bluefish River in Alaska. It also stated that the horse jawbone in question was dated to 24,800 years, rather than 24,000.
Excellent link dave.
As I stated in the previous article, many linguist are certain that the first people were here at least 50,000 years ago based on language, how it developed and spreads.
The Bering theory, and the 10,000 stop over plus the kelp highway all have some good point. A combination of those is probably more likely. That does not explain the 16,000 plus years old of the tools discovered in Texas or the mummy's discovered in Peru that are estimated to be 25,000 years old.
The recent dig outside of San Diego CA. where they are saying humans could date back 130,000 years. Each new discovery is going to change the time line and quite possibly the from where they came and the time interval's.
Northern Canada and Alaska were though to be a wasteland for archaeological discoveries until the last few years when very important discoveries have been made.
IMO, the Clovis people were not the first people here in the Americas. Although very important they, IMO, where part of a mass migration that covered tens of thousands of years.
As for an event that could have changed the face of north American, I submit the eruption of the Super Volcano, Yellowstone 174,000 year ago. The effects of this would have lasted for centuries.
While the 130K BP site isn't a certainty this is the part I find most interesting:
.
It would make sense that southern migration would occur during a glacial max period but the problem then becomes that any coastal migrations routes would be at least several hundred feet under water today. There may well be inland sites discovered in the future which have stronger evidence of early hominid habitation but the odds are working against some random construction crew accidentally hitting paydirt much less recognizing it when they do.
Quite true, the recent discovery in Mexico shows that there is a lot more to be discovered off shore. The same can be said of discoveries off the coast of Florida and CA.
Exciting times.
Agree. There is a good chance most of the ancient record is under water. This could be good or bad for preservation depending of the situation. For example the anaerobic layer of the black sea does an excellent job of preservation.
I guess, depending on the microbes and other environmental variables from site to site, some stone age items may hold up better than other.
It probably would depend on how fast the sea level rose and how exposed the site was to wave action. There's a well-preserved Cypress forest in the gulf off the Louisiana coast (presumably buried in silt due to some hurricane event) which has been dated at 60K BP. Apparently it was exposed as a result of hurricane Ivan. But for most human artifacts on coastal migration routes I suspect wave action alone would obliterate it without some kind of similar preservation event - a mud slide, deposition of volcanic tuff, very rapid sea level rise, etc.
While I agree with that Skerkk there is the possibility that in some case the water grave may be a protector of artifacts.
On the Channel islands off the coast of California which it seems were attached to the coast of CA are providing great archaeological discoveries.
Hopefully with more interest and advanced tech we can start exploring the water areas that may lead to even great discoveries.
Thank you Kavika.
It is notable that evidence continues to mount which pushed the date of human arrival to the Americas back further almost on a yearly basis now.
It took a very long time to develop a foundation of knowledge, methods and tools. Now the work done in the past is beginning to show benefits which allows progress to accelerate.
The conditions here in the Americas for this work can be a challenge compared to the more arid regions around the globe. Yet technology is opening doors of discovery.
Imagine going back just 10 years in time and proclaiming evidence of ancient humans having lived 130K years ago in what is now southern California. That story would not fly 10 years ago. Now these findings are something people will consider worth investigating.
If this discovery turns out to be true, who really where they? Some theories are in place but you have to ask, where did they come from? How did they get here? where did they go? Or, are they still here in one form or another?
Each discovery opens up new and interesting questions.....This, IMO, is one damn exciting time in our history.
The discoveries in Central and South American in the last few years are simple mind boggling.
I just love this.
To help stir thought and discussion I am going to post some temperature graphs in 3 different scales. Current date is to the right on all 3 graphs and they will run from larger time frame to smaller time frame:
Unfortunately, I need to leave for an hour or two. Feel free to give thought and comment.
I'll be studying them while your gone dave.
The huge jump in the eemian period around 130,000 years ago and the built up to it starting around 150,000 years ago isn't quite in the yellowstone time frame but close. if 25,000 years can be called close. But in the frame of time reference being discussed it could be connect.
Well, I'm back for a little bit.
Looking at the top graph there is a plunge in temperature right around and after the Yellowstone event. It remained cold for quite a while too.
Then it looks like the earth went back into a warmer interglacial period beginning around 140K years ago.
By about 110K years ago earth was back into a full on glacial period again.
About 75K years ago another catastrophic event happened. The super volcano Toba erupted. Toba is in Sumatra. Famous for explosive volcanoes. The Toba event was actually larger than the Yellowstone event.
Notice the dip in temperatures around and after the time of each super volcano event. Curiously enough, there was a near human extinction which occurred during this time frame. Toba has been blamed for the temperature drop and the near human extinction. Until recently, as some are claiming something else caused the near extinction.
Then about 17K years ago the earths temperatures began climbing back up out of the glacial period again.
Temperatures then fall a little bi until they plunge back into an glacial period about 13.5K years ago and this cold period, called the Younger Dryas stayed around 2 - 2.5 thousand years.
The layer of strata in which the black mat is coincides with the beginning of the Younger Dryas.
Something caused the black mat. All Clovis artifacts and megafauna findings end where the black mat begins.
It appears something happened here, more than just a cycle in the earths climate.
I have to agree dave. It's really doesn't make a lot of sense that the clovis people and the megafauna all disappeared at the same time. Over hunting just doesn't make sense.
But what is it that caused this...Mysteries and discoveries.
Exactly Kavika, one wonders what exactly were the chain of events that caused this?
Some folks think an ancient glacial lake, Lake Agassiz, played a role when it emptied into the Atlantic and brought the "Atlantic Conveyor" aka Thermohaline circulation by diluting the salt content of the ocean.
The significance of this is happening is the loss of the Gulf Stream, which we know warms the northern latitudes. The door would now be open for another Ice Age, we also know as a Glacial Period.
If, this was the DIRECT cause of the Younger Dryas, then of course, there are more questions. Why and how did the lake do this?
Let me see if I can post a gif of the lake running dry over a 4,000 year period of time. It goes through 1,000 year increments and takes some time doing so.
Although this gif shows the progression of the lake shrinking in size as it's water flows into the Atlantic, the timing simply does not align with the period of the Younger Dryas. We can clearly see this when comparing the dates of the graph with the date on our previous 3iIce core graphs.
If you look at our ice core graphs, the Lake Agassiz event better correlates with the 8,200 year event, which is a topic onto itself that we need to get to.
I will get the article behind this gif and put up in a separate post.
The sheer size of the lake is hard to comprehend...One of the lakes that it left behind was Lake of the Woods that is in both Canada and Minneosta. The interesting thing is that I grew up on the shores of Lake of Woods, in Warroad MN. Lake of the Woods is 70 miles by 70 miles with 14,000 islands on it.
Got it. This is a dated article and you will see dated information in it. Yet, there is true information needing separating from Younger Dryas event and disappearance of the Clovis.
Palaeo Period
10,000 to 6,000 BC
Glacial Retreat and Aboriginal Settlement
At the outset of the Palaeo Period, much of what is now Manitoba was covered by thick glacial ice, kilometers deep in places, and the meltwater which formed Lake Agassiz . The first Native inhabitants, loosely referred to as " Clovis peoples " entered the province from the southwest, where the high ground provided a small corner of dry, ice free land. The landscape they saw differed from the modern prairie. It was covered with spruce groves and hardy grasses which supported herds of mastodons, mammoth and giant bison, abundant sources of meat, bone, hides, antlers, and ivory. A handful of spear heads provides the only evidence of this early human presence. During the following Folsom phase , Lake Agassiz began its gradual retreat, opening wider opportunities for settlement. Hunting groups migrated intonew territories and occupied many parts of province during Plano times at the end of the period.
Early Palaeo Period (10,000 - 8,000 B.C.)
(Raw image is terrible. The stone work, especially the fluting, of both the Clovis and Folsom are not discernible)
Early Palaeo Points
A. Clovis
B. Folsom
Late Palaeo Period (8,000 - 6,000 B.C.)
The second half of the Palaeo Period saw a significant spread of people into new environments and a general increase in population and human activity in Manitoba. The climate moderated and the ice sheets and glacial lake retreated. Open grasslands became prevalent and supported the migration of bison herds into new areas. Native groups in Manitoba and elsewhere in the Plains developed a subsistence technology and way of life that specialized in bison hunting, which was to serve as the mainstay of Aboriginal life in many parts of the province until the period of European settlement. The cultural remains are classified as Plano , after the Spanish term for plains, in recognition of their extensive distribution in this region.
In Manitoba, the Plano traditions are divided into three geographical variants:
Plano Points
In response to the environmental and subsistence changes at the end of the Palaeo Period, Plano groups made substantial improvements in hunting technologies and strategies. They manufactured spear points according to many new styles. Stemmed points (B and D) were produced with indented bases in accordance with new hafting techniques. Lanceolate (i.e. lance shaped) forms (A and C) were so beautifully crafted that archaeologists believe some items may have been intended as ceremonial art rather than practical weaponry. Plano peoples also left some traces of their innovative hunting methods, which incorporated the strategy of the bison jump, a forced stampede of a herd over a cliff or river terrace.
The Palaeo Period ended around 6,000 B.C. with the final cessation of the Ice Ages and the extinction of many big game species. More temperate climates and changes in human hunting and gathering techniques established the foundation for the next period, the Archaic.
====================================================================
Would you like to:
Learn more about the Palaeo Period in Manitoba
Go to the Archaic Period
Visit a companion Internet site about the Palaeo period in:
Return to the General Overview
It is mind boggling. There was a similar glacial lake further west that broke a glacial dam that bewildered the science community for the longest time. I am a little bit at a loss for the details right now, but the fella who came up with the solution was ostracized by the established scientific community for decades until a person who sat in on the original presentation and kept a key piece, that of information to his self during that presentation. I can only think he was fearful of being ostracized as well.
It was Lake Missoula. The river bed it created was immense and left behind a scene that baffled all but 1, okay 2, at the time.
This is very cool, the discovery of ''Montana Boy''. The DNA testing on him showed that the Clovis people and modern NA's are linked. He lived 12,600 years ago. His body was found near Livingston Montana which would make it just west of Lake Agassiz and close to Lake Missoula...That would make it pre Palaeo period.
Still, there is no answer for the Younger Dryas.
Especially the coinciding of the black mat, and disappearance of both the Clovis and megafauna at the same time.
However, there is a paper going through review by climate scientists peers, a few students and some average Joes.
I will present it under the condition that it does not lead to political discussion.
No I have to go find it.
NO POLITICS AT ALL...PERIOD.
A fantastic find. Thank you.
Two quotes stand out in my mind:
I wonder, could this be a part of the answer of where the Clovis wound up?
and
Pushes back on conventional assumptions of no written record.
Look at the points, both in your link and the my previous article. That required craftsmanship. The arrow heads we have made are child like by comparison and we had modern tools.
I saw that about the being more closely related to central south American Indians...
That does bring up the theory of the reverse migration. Some contend that at one point in time the natives moved back across the Bering sea to Siberia...That opens up a whole new area.
Science is finding that the oral history of tribes is very very accurate and goes back thousands of years.
Among the Ojibwe in MN. there is part of our oral history that refers to ''white Indians''...Most feel that they are talking about the Vikings...At one point a few years ago science that they had found Viking stones on a farm in MN. Turns out that they were not, but there are so many oral history that bear a lot of investigation.
Actually the article, from 2012, is a few years older than I recalled. Following the link and scrolling to the comments section shows the questions and agreements raised. Remember, these are mostly Climate scientists. Reading with discernment will quickly identify the students and average Joes.
Either way, it is a light year ahead of the previous article.
The Intriguing Problem Of The Younger Dryas—What Does It Mean And What Caused It?
This is a follow up posting to Younger Dryas -The Rest of the Story!
Guest post by Don J. Easterbrook
Dept. of Geology, Western Washington University.
The Younger Dryas was a period of rapid cooling in the late Pleistocene 12,800 to 11,500 calendar years ago. It followed closely on the heels of a dramatically abrupt warming that brought the last Ice Age to a close (17,500 calendar years ago), lasted for about 1,300 years, then ended as abruptly as it started. The cause of these remarkably sudden climate changes has puzzled geologists and climatologists for decades and despite much effort to find the answer, can still only be considered enigmatic.
The Younger Dryas interruption of the global warming that resulted in the abrupt, wholesale melting of the huge late Pleistocene ice sheets was first discovered in European pollen studies about 75 years ago. Terrestrial plants and pollen indicate that arboreal forests were replaced by tundra vegetation during a cool climate. This cool period was named after the pale yellow flower Dryas octopetella, an arctic wildflower typical of cold, open, Arctic environments. The Younger Dryas return to a cold, glacial climate was first considered to be a regional event restricted to Europe, but later studies have shown that it was a world-wide event. The problem became even more complicated when oxygen isotope data from ice cores in Antarctica and Greenland showed not only the Younger Dryas cooling, but several other shorter cooling/warming events, now known as Dansgaard-Oerscher events.
The Younger Dryas is the longest and coldest of several very abrupt climatic changes that took place near the end of the late Pleistocene. Among these abrupt changes in climate were: (1) sudden global warming 14,500 years ago (Fig. 1) that sent the immense Pleistocene ice sheets into rapid retreat, (2) several episodes of climatic warming and cooling between ~14,400 and 12,800 years ago, (3) sudden cooling 12,800 years ago at the beginning of the Younger Dryas, and (4) ~11,500 years ago, abrupt climatic warming of up to 10º C in just a few decades. Perhaps the most precise record of late Pleistocene climate changes is found in the ice core stratigraphy of the Greenland Ice Sheet Project (GISP) and the Greenland Ice Core Project (GRIP). The GRIP ice core is especially important because the ages of the ice at various levels in the core has been determined by the counting down of annual layers in the ice, giving a very accurate chronolgoy, and climatic fluctuations have been determined by measurement of oxygen isotope ratios. Isotope data from the GISP2 Greenland ice core suggests that Greenland was more than~10°C colder during the Younger Dryas and that the sudden warming of 10° ±4°C that ended the Younger Dryas occurred in only about 40 to 50. years.
Figure 1. Temperature fluctuations over the past 17,000 years showing the abrupt cooling during the Younger Dryas. The late Pleistocene cold glacial climate that built immense ice sheets terminated suddenly about 14,500 years ago (1), causing glaciers to melt dramatically. About 12,800 years ago, after about 2000 years of fluctuating climate (2-4), temperatures plunged suddenly (5) and remained cool for 1300 years (6). About 11,500 years ago, the climate again warmed suddenly and the Younger Dryas ended (7).
Radiocarbon and cosmogenic dating of glacial moraines in regions all over the world and abrupt changes in oxygen isotope ratios in ice cores indicate that the Younger Dryas cooling was globally synchronous. Evidence of Younger Dryas advance of continental ice sheets is reported from the Scandinavian ice sheet, the Laurentide ice sheet in eastern North America, the Cordilleran ice sheet in western North America, and the Siberian ice sheet in Russia. Alpine and ice cap glaciers also responded to the abrupt Younger Dryas cooling in both the Northern and Southern hemispheres, e.g., many places in the Rocky Mts. of the U.S. and Canada, the Cascade Mts. of Washington, the European Alps, the Southern Alps of New Zealand, and the Andes Mts. in Patagonia of South America.
Figure 2. Temperature fluctuations over the past 15,000 years showing the abrupt cooling during the Younger Dryas and other warming and cooling periods, the Oldest Dryas (cool), Bölllng (warm), Older Dryas (cool), Allerød (warm), InterAllerød (cool), and Younger Dryas (cool).
Figure 3. Oxygen isotope record from the Greenland ice core showing an abrupt temperature drop 12,800 years ago, 1300 years of cool climate, and sudden warming 11,500 years ago.
The Younger Dryas had multiple glacial advances and retreats
The Younger Dryas was not just a single climatic event. Late Pleistocene climatic warming and cooling not only occurred before and after the YD, but also within it. All three major Pleistocene ice sheets, the Scandinavian, Laurentide, and Cordilleran, experienced double moraine-building episodes, as did a large number of alpine glaciers. Multiple YD moraines of the Scandinavian Ice Sheet have long been documented and a vast literature exists. The Scandinavian Ice Sheet readvanced during the YD and built two extensive end moraines across southern Finland, the central Swedish moraines, and the Ra moraines of southwestern Norway(Fig. 4). 14 C dates indicate they were separated by about 500 years.
Figure 4. Double Younger Dryas moraines of the Scandinavian Ice Sheet.
Among the first multiple YD moraines to be recognized were the Loch Lomond moraines of the Scotish Highlands. Alpine glaciers and icefields in Britain readvanced or re-formed during the YD and built extensive moraines at the glacier margins. The largest YD icefield at this time was the Scotish Highland glacier complex, but smaller alpine glaciers occurred in the Hebrides and Cairngorms of Scotland, in the English Lake District, and in Ireland. The Loch Lomond moraines consist of multiple moraines. Radiocarbon dates constrain the age of the Loch Lomond moraines between 12.9 and 11.5 calendar years ago.
Multiple Younger Dryas moraines of alpine glaciers also occur throughout the world, e.g., the European Alps, the Rocky Mts., Alaska, the Cascade Range, the Andes, the New Zealand Alps, and elsewhere.
Figure 5. Double Younger Dryas moraines at Titcomb Lakes in the Wind River Range of Wyoming.
Implications
The multiple nature of YD moraines in widely separated areas of the world and in both hemispheres indicates that the YD consisted of more than a single climatic event and these occurred virtually simultaneously worldwide. Both ice sheets and alpine glaciers were sensitive to the multiple YD phases. The GISP2 ice core shows two peaks within the YD that match the glacial record. The absence of a time lag between the N and S Hemispheres glacial fluctuations precludes an ocean cause and is not consistent with the North Atlantic Deep Ocean Water hypothesis for the cause of the Younger Dryas, nor with a cosmic impact or volcanic origin.
Both 14 C and 10 Be production rates in the upper atmosphere changed during the YD. 14 C and 10 Be are isotopes produced by collision of incoming radiation with atoms in the upper atmosphere. The change in their production rates means that the Younger Dryas was associated with changes in the amount of radiation entering the Earth’s atmosphere, leading to the intriguing possibility that the YD was caused by solar fluctuations.
Why the Younger Dryas is important
What can we learn from all this? The ice core isotope data were hugely significant because they showed that the Younger Dryas, as well as the other late Pleistocene warming and cooling events could not possibly have been caused by slow, Croll-Milankovitch orbital forcing, which occurs over many tens of thousands of years. The ice core isotope data thus essentially killed the Croll-Milankovitch theory as the cause of the Ice Ages.
In an attempt to save the Croll-Milankovitch theory, Broecker and Dention (1990) published a paper postulating that large amounts of fresh water discharged into the north Atlantic about 12,800 years ago when retreat of the Laurentide ice sheet allowed drainage of glacial Lake Agassiz to spill eastward into the Atlantic Ocean. They proposed that this large influx of fresh water might have stopped the formation of descending, higher-density water in the North Atlantic, thereby interrupting deep-water currents that distribute large amounts of heat globally and initiating a short-term return to glacial conditions. If indeed that was the case, then the Younger Dryas would have been initiated in the North Atlantic and propagated from there to the Southern Hemisphere and the rest of the world. Since that would take time, it means that the YD should be 400-1000 years younger in the Southern Hemisphere and Pacific areas than in the Northern Hemisphere. However, numerous radiocarbon and cosmogenic dates of the Younger Dryas all over the world indicate the cooling was globally synchronous. Thus, the North Atlantic deep current theory is not consistent with the chronology of the Younger Dryas.
The climatic fluctuations before and after the Younger Dryas, as well as the fluctuations within it, and the duration of these changes are not consistent with a single event cause of the YD. Neither cosmic impact or volcanic eruptions could produce the abrupt, multiple climatic changes that occurred during the late Pleistocene.
Yes, you wonder about what was going on there in and across the land bridge area, especially when considering the possibility of potential geologic upheavals.
This sparks another thought actually. Western Siberia was known for different types of Points, and Cutting tools. Instead of precision crafted points and other cutting tools, they took bone, antlers, ivory or even wood, cut grooves and inserted fine, small, sharp stone flakes which created a different form of the stone age lethal weapons. Yet, and I am going on some rusty memory here, IIRC, along the way Clovis like points were found that dated more recent than what were considered the time frame of when Clovis originally migrated to North America.
In other words, if correct, Clovis like tool found in North America were found in Siberia AFTER Clovis were known to exist in North America.
If true, the reverse migration could very possibly result in something like this.
That was damn interesting and will take some time to digest...
If the drainage of Lake Agassiz to the east/Atlantic Ocean would it not have affected the Hudson Bay area first. I would think that would leave some evidence to that fact.
I would think so too, but maybe that would depend on the path it took to flow east. ?
One thing different between how Lake Agassiz flowed into the Atlantic vs how Lake Missoula flowed into the Pacific, is the length of time for each event. Lake Agassiz emptied across a prolonged period of time, which brings into question any halting of the Atlantic thermohaline circulation. Whereas, Lake Missoula emptied in a sudden catastrophic event which left marked evidence.
Need to catch some Zs. Giving thought to the next Younger Dryas post, as we have seen there is credible speculation that more than a single event could have caused it. I'll go deeper into your other links once I've settled how to organize my next post.
What I found interesting and, this would give rise to the possibility of people surviving a catastrophic event along the west coast and, in the south during the Younger Dryas is what is being discovered in the north east U.S. and, Canada.
The possibility of an asteroid or, comet hitting somewhere around Quebec is still a possibility even though to evidence of a crater has been found......yet.
Good link Galen...An event that did not affect the west coat but the northern areas is well within the realm of possibility.
Galen, the article you presented aligns well with evidence uncovered by another group of researchers. I will have to find the link later and there is also a youtube vid documenting their research.
These folks were also looking at the comet/meteor impact theory. One of the early trails they followed was a layer of meteoric iridium such as found in combination the Chicxulub impact that is credited with the dinosaur extinction.
The team found indicators of increased iridium levels relative to the Younger Dryas, however the levels were not convincingly high enough to draw conclusions.
Then the team did some brainstorming about the missing crater.
Of course we have examples of the Tunguska event of 1908 and more recently the Chelyabinsk event of 2012.
Anyhow, the team conducted tests where a small glass bead was accelerated at very high velocities and was shattered prior to hitting a sand target. The impact dynamics of these test and how the energy was released into the sand target matched up with their expectations of how a large object exploding in the atmosphere prior to impact could disperse the energy enough to significantly reduce noticeable crater creation.
So the team had a hint of an iridium layer and in their minds a way to explain a missing noticeable single crater. But still not enough evidence to come forward to offer their theory.
They needed something something of weight to tie the other to components together in support of the impact theory.
Some thought brought of the question of other byproducts which can be produced by other worldly objects making earthy impact. This team settled on nano diamonds with a hexagonal carbon lattice structure, similar to graphite as opposed to a cubic structure found in conventional earthly diamonds.
Turns out the hexagonal structure is formed under extreme (even for diamonds) pressures, like in an impact.
The team then went to gather ice from the Greenland ice shelf from the period leading to the Younger Dryas. I believe on their very first hit, they hit pay dirt.
So now they can pull all 3 building blocks together for their hypothesis.
This platinum layer find from the same period adds their work.
All that said, there is growing thoughts of multiple events resulting in the Younger Dryas as discussed some of the prior posts.
Then we also can not forget about the black mat, above which Clovis and N.A. magafauna can not be found.
Of course the geologic record shows multiple black mats, for this discussion we are only concerned about the one just above the Clovis and N.A. megafauna.
This is exactly what I was going to post re: black mat.
There is also the super volcano that is Yellowstone to consider.
Either of these things could have caused it.
Hi Perrie, or both plus some other events. ? My personal opinion about the Yellowstone event, looking at the time frames of it and the Younger Dryas, there appears to be a mismatch especially considering the Toba event happened much closer in time scale and was a larger event. Hey, who am I?
If it is possible to mute the immature language, this could be a good report from the Nerd Alert network on the Chelyabinsk event. She took the time to give the understanding as to why space object traveling through earths atmosphere can explode prior to impact and separated the obeject from a known predicted object expected that same day.
This vid gives good examples of the ground level effect of this explosion.
I almost forgot about this find. The oldest human footprints found on island off B.C.
Or this amazing discovery on Alaska island.
Those are some great articles Kavika. A statement in the NY Times article caught my attention:
Unless there is something I don't understand, I thought the sea level was much lower than that.
I found this graph and am not sure how to correlate this graph with the NW Times published statement. Present time is to the left.
Nonetheless, I couldn't imagine walking around on that island barefoot today, let alone 13 - 14K years ago. Were they drying their footwear? Or is that how they went about life?
Western Digs is a good site. Intriguing the Mammoths survived until 5,600 years ago. Then this very well may be a documented example of climate change resulting in an extinction.
You are right this is an amazing time to be living. With each new discovery there is a sense of connecting to those who came before us.
I see the monthly subscription fee, How long is the site accessible before getting blocked?
I've been on the Westerdiggs site for a couple of years now and have never had it blocked dave.
dave, Skerkk or anyone interested here is a link to a site that I follow closely. Of course I spend most of my time on the discoveries in the Americas.
Here is a link to an article on how language plays into all of this..This is just one article on it, there are many more.
Thanks - that's a great site.
Thanks Kavica.
I almost forgot about this discovery. Although it doesn't exactly correlate to what we are discussing here I found it really interesting.
700,000 year old DNA from a horse discovered in...guess where...The Yukon..
We are talking about 200,000 years of unrecorded evolution and history, much of could have been buried by changes in shorelines and water levels. IE., "the missing link".
Many physiological features are poorly explained by traditional, main line biologists and anthropologists .
We always keep this book available to anyone willing to read with an open mind.
We have much in common with other mammals from 400 or 500 thousand years ago
which explains why other mammals, are so effing smart,
we are all connected.
Gakina Awiiya.
lmfao
You find the discovery funny?
Here is a link to a very important discovery in the interior of Alaska. The skeleton did yield DNA and testing showed it to be 11,000 years old. This, in a way, seems to support the 10,000 year stop over from Siberia.
Another great link Kavika.
The Epilogue grabbed my attention as much as anything in the article:
Along with the researchers models, many migration theories under consideration are under the umbrella of this story.
I need to ask, are there any Native legends depicting a situation falling under what we are reading in this article, especially relative to the description of the migrations described?
Speaking only for the Ojibwe, PBS did a six part series named ''Wassa Inaabidaa'' (we look in all directions) Fantastic series and very in depth with contributions from many Ojibwe bands/scientists. Well researched and presented. This covered mostly the last 1K years and the migration from the east coast moving west. Which would be present day Michigan, Wisconsin, North Dakota, Minnesota, Montana and three Canadian provinces. Prior to that most oral history has us moving from the north and west of Hudson Bay and the East Coast to those location. This seems to indicate that we migrated from the areas of Alaska being discussed to the east coast and then spread across Canada and the upper midwest of the U.S.
What is interesting and science does not have an explanation for this. The Cowrie shell and more directly the Miigis shell is sacred to the Ojibwe, yet the only place that it is found is in certain parts of the South Pacific, yet here the shells are in the Hudson Bay region...Explain that if you can...LOL
To go back to an earlier part of the discussion regarding many sites being underwater and damage that would cause the site. I did state that it's possible that it also protected some sites from destruction. Case in point the discovery of a complete young girl skeleton from a Mexican underwater cave.
Here is another excellent example where by a ancient burial site has protected by possibly a fresh water peat bank..
The site has been preserved in what appears to have been a "peat-bottomed freshwater pond" from thousands of years ago, according to news release.
Link...
I will have to look for that. Some youtube channel might have it. The origin of those shells in the Hudson area deserves investigation.
P.S. I am one of the non-tv people. Haven't had one in 10 years.
Wow.
It is amazing the peat has the ability to preserve so well. Almost like the Black Sea anaerobic layer. Good to see the researchers understand the similar submerged sites may exists. Hopefully all or most of the scientific community will take this realization into consideration.
Black Mat, Megafauna, Clovis Peoples, Iridium Layer, Carbon Spherules, Hexganol Nano Diamonds, Lake Agassiz Drainage through the Hudson, Younger Dryas Impact Theory
The following video is a synopsis of many of the things discussed in this article to date. Notice the repetition of the now questioned theory causing the Younger Dryas, namely Lake Agassiz draining through the Hudson into the Atlantic and stopping the "Atlantic Conveyor" aka Thermohaline circulation by diluting the salt content of the ocean.
A fairly long video but well worth watching.
Thanks dave.
Thank you Kavika.
The video does a good job of tying together many of the points we have covered while moving forward in the direction I intended a couple weeks ago when technical difficulties caused a little issue.
Finding this video, in the meantime, saved about 4 or five posts to convey the same information. Now we have room for some more discussion, for example a revisit of the disappearance of the Clovis People and NA Megafauna. Not to mention more theories as possible causes for the Younger Dryas.
Although the timeline may be off, the Meteor Crater asteroid may have had some play in this. While not large enough to have a worldwide effect, it may have had an impact on the local areas. Would explain the demise of both the fauna and the Clovis at the same time.
My early morning hypothesis at least.