So, it wasn't humans after all

[Gaf The Horse With Tears]

some day, we are going to get over our ego and stop blaming everything on those pesky humans...

Study: Diamonds link comet to mammal extinction

(CNN) -- Tiny diamonds found in the soil are "strong evidence" a comet exploded on or above North America nearly 13,000 years ago, leading to the extinction of dozens of mammal species, according to a study.

The scientific report also suggests the cataclysm also reduced the population of the earliest people to inhabit the region and triggered a 1,300-year-long cold spell that stretched around the world.

The heat generated by the extraterrestrial impact likely melted much of a glacier that once covered the Great Lakes region, sending a massive flood down the Mississippi River, the study said.

According to the report, the cold waves of glacial runoff into the Gulf of Mexico shifted Atlantic Ocean currents, changing climate patterns throughout the world in a cooling period known as the Younger Dryas.

"A rare swarm" of comets rained over North America about 12,900 years ago, sparking fires that produced choking, leading "to the extinction of a large range of animals, including mammoths, across North America," the report said.

The study was conducted by a group of eight archaeologists and geologists from the universities of Oregon and California, Northern Arizona University, Oklahoma University and DePaul University. Their findings were published Friday in the journal Nature.

The prehistoric humans known to have inhabited the continent at the time of the event -- hunters and gatherers dubbed the Clovis culture -- suffered a major decline in population in the aftermath, the scientists said.

The scientists, studying layers of sediment dated to 12,900 years ago at six North American locations, including one directly on top of a Clovis site in Murray Springs, Arizona. Each layer was rich in nanodiamonds, which are produced under high-temperature, high-pressure conditions created by cosmic impacts, the report said.

"The nanodiamonds that we found at all six locations exist only in sediments associated with the Younger Dryas Boundary layers, not above it or below it," said University of Oregon archaeologist Douglas Kennett. "These discoveries provide strong evidence for a cosmic impact event at approximately 12,900 years ago that would have had enormous environmental consequences for plants, animals and humans across North America."

The other sites studied were in Bull Creek, Oklahoma; Gainey, Michigan and Topper, South Carolina, as well as Lake Hind, Manitoba; and Chobot, in the Canadian province of Alberta.

[paradox]

quite interesting.

[TomCat]

Interesting indeed...damn comet swarms!

[Gaf The Horse With Tears]

I've never bought that humans caused the Mammoths to go extinct. There has never been any proof of it, just conjecture based solely on the fact that early humans lived at the same that Mammoths went extinct.

[TomCat]

I've never bought that humans caused the Mammoths to go extinct. There has never been any proof of it, just conjecture based solely on the fact that early humans lived at the same that Mammoths went extinct.

Well, primitive man, the types we dig up from time to time in Ethiopia, the Andes, and Euphrates regions, for examples, have been shown to have fallen victim to the same fate as did many of our "beloved extinct species." There are a lot of theories and evidence to point to catastrophic periods of soot layers. They point to the meteor/comet impact theories. We have craters, they surely caused environmental turmoil after impact...so there ya have it.

[Msterbeau]

It was space aliens I tell ya!!!!!

[TomCat]

It very well could've been those pesky underwear gnomes again too!

[Simon Bar Sinister]

Interesting idea...some impact craters would be nice...

[Homicidalheathen]

when were humans blammed, they were not around yet

[Troy Spiral (13)]

when were humans blammed, they were not around yet

Your probably thinking of them as dinosaurs HH. Mammoths, Saber toothed cats and such were still alive 10,0000 years ago or some such and were alive with humans. (Homo Sapiens being around for the last 100,000 - 200,000 years ago ish without looking the specific figures up)

The last I remember Mammoths are believed to have died off due to a combination of climate shift and other factors along with human interaction. Usually I hear something like "they were already going extinct and were corralled into smaller and smaller areas... we just inflicted some of the final killing and/or weakening blows"

This study here puts a finer point and focuses the lens so to speak, on such generalized hypothesis, that is a comet killed off a ton of life, humans and animals alike, during the late stages of the Mammoths being around.

[Homicidalheathen]

humans could be responsible then I suppose, we are wiping out the chupacabras before we have proof after all...(just kidding...half assed at least)

[Gaf The Horse With Tears]

You are missing the point HH, this goes toward proving that it was NOT humans.

BTW, I just watched two shows in the last month on Discovery that put all blame for the Mammoths dieing off squarely on early humans. I have seen a few posts here on this board that blaming early humans.

Spammer, an impact crator would be a nice thing, but I doubt one would be found as at the time... the general areas that were affected and the suspected impact area were deep under ice... like a mile of it. Also, it took many many years to find a canidate crator for the Dino's dieing off. We still don't even know if the one in the Yukatan/Gulf of Mexico is right.

[Gaf The Horse With Tears]

Another take on it... I bolded teh most relevant things.

New Theory on Old Debate: Comet Killed the Mammoth

By Christopher Lee

Washington Post Staff Writer

Monday, June 11, 2007; Page A06

There are intriguing new clues in the mystery of how the woolly mammoth met its demise in North America more than 10,000 years ago.

For decades, scientists have debated whether the giant, elephant-like beasts were driven to extinction by the arrival of overzealous human hunters or by global warming at the end of the Pleistocene era, the last great Ice Age. Some say it was a combination of the two.

Recently, a group of more than two dozen scientists offered a new explanation. They have found signs that a comet -- or multiple fragments of one -- exploded over Canada about 12,900 years ago with the force equivalent to millions of nuclear weapons. That unleashed, they said, a tremendous shock wave that destroyed much of what was in its path and ignited wildfires across North America.

Another group, with the help of DNA evidence extracted from mammoth bones, teeth and ivory, has for the first time identified two distinct genetic groups among mammoths. They found that one group had died out by 40,000 years ago for unknown reasons, leaving the second to continue until the species went extinct.

The comet blast and firestorm could have dealt that death blow to the mammoth and more than 15 other species of large mammals, or "mega fauna," including the mastodon, the saber-toothed cat, the American camel and the giant ground sloth, the other researchers said. They presented their findings last month at a meeting of the American Geophysical Union in Acapulco.

"The shock wave would have spread across the whole continent," said Richard B. Firestone, a nuclear chemist at Lawrence Berkeley National Laboratory in California who helped do the research. "This event was large enough to directly kill most everything instantly. Those that survived would have found their food sources devastated, their water polluted, all kinds of things that would have made it difficult to go on much longer."

In more than 20 locations from Arizona to Canada and California to the Carolinas, the scientists found glass-like carbon, microscopic diamonds, enriched iridium and other materials that they say are indicative of an extraterrestrial impact lying in a sediment layer corresponding to the time period. Just above that layer they found charcoal soot, decayed plant life and other debris consistent with widespread burning.

Above that, the remarkable thing is what they did not find: further evidence of the mammoth and the other large animals.

"The mammoths come up to the line and not beyond it," said James Kennett, a marine geologist and professor emeritus at the University of California at Santa Barbara. "At some sites, the black layer with impact material shrouds the bones."

The explosion may also have spelled the end for the Clovis culture, the prehistoric North Americans who hunted with distinctive stone spearheads that have been found in the bones of the fossils of mammoths and other animals, researchers said. While humans as a species survived the cataclysm, the Clovis culture and its relatively advanced stone tools did not endure.

"At many Clovis sites, like in Arizona and New Mexico, you get the Clovis tools up to the impact layer, and then they never go beyond it," Kennett said.

The comet theory, while adding a new twist to the tale, is not wholly incompatible with earlier explanations for how the mammoth met its end. Researchers said it is possible that the Ice Age beasts, which stood about 9 feet tall and weighed three tons, struggled as the climate warmed, that increasingly skilled and numerous human hunters dramatically thinned their numbers, and that the exploding comet finished them off.

"Our theory is that if this event had not happened, that mammoths would still most likely -- not certainly, but most likely -- be wandering around North America now," said Allen West, a retired geophysicist who is a leader of the research team. "Almost certainly, humans hunting animals can have a major effect on populations. It seems like there was, in a sense, a perfect storm going on -- of overkill, the comet, climate change, possibly disease. I don't think this theory negates any of the other theories. It's just one more of a mix of things that were absolutely lethal to these animals."

The scientists have not published their findings, although two papers are under review by the National Academy of Sciences, Kennett said. Firestone said the lack of a distinctive impact crater -- the airborne explosion did not leave one -- has generated controversy. Even some who accept that the explosion occurred question whether it was the definitive blow, he said.

The second group of researchers, in a study published last week in the journal Current Biology, analyzed mitochondrial DNA from 41 mammoths from Europe, Asia and North America. Radiocarbon dating found the oldest of the mammoths lived about 50,000 years ago, and the most recent specimens were from about 12,000 years ago.

Scientists found two distinct genetic groups among mammoths in northeast Siberia, indicating that the animals probably had existed in isolation during a warm phase thousands of years earlier and had come together when the glaciers -- and their habitat -- expanded again. Why one group died out they do not know, but the loss of genetic diversity theoretically leaves a species more vulnerable because the remaining population may be less able to adapt to changing conditions, the researchers said.

They will discuss their research this week at the Fourth International Mammoth Conference in Yakutsk, Russia.

"In terms of understanding the process of extinction, we've learned something -- that it's not something that just happens in a flash everywhere and they're all gone," said Adrian Lister, a professor of paleobiology at the Natural History Museum in London. "It seems to have been a progressive reduction in the genetic diversity of the species over tens of thousands of years."

Colleague Ian Barnes, a senior lecturer in biological sciences at Royal Holloway, part of the University of London, said it is likely that there was "a slow grinding down" of genetic diversity.

"What we're now starting to think is . . . there is no single event that causes their extinction," Barnes said. "What's important is that we seem to have the conditions for extinction set up a long time before the actual extinction occurs."

[Simon Bar Sinister]

You are missing the point HH, this goes toward proving that it was NOT humans.

Actually, it doesn't. The longer piece (containing your selected sections in bold) makes no such claim; indeed, a part that wasn't emphasized draws a "last straw" scenario.

I want to ask you something: what is it about the idea/theory of prehistoric-human-caused extinctions that bothers you?

[candyman]

Actually, it doesn't. The longer piece (containing your selected sections in bold) makes no such claim; indeed, a part that wasn't emphasized draws a "last straw" scenario.

I want to ask you something: what is it about the idea/theory of prehistoric-human-caused extinctions that bothers you?

Why shouldn't it bother anyone? Hell, people are spending so much time and money on shit just to make some short film on the discovery channel that ends with doom like music and a speech about how if we don't stop now it will only get worse. Well, unless I have damn hard evidence that things need to change because they will cause something to happen I see no point in spending so much of my time and my money changing to things that someone else says will help.

I know people say this alot but if all these important people really do care this much about the earth they will lead by example. But no they never do. They keep their houses and cars, their jets and their boats. They purchase these "earth friendly" products and when I look up what they cost, I shit a brick. When I look up how much more efficient they are than conventional systems I fail to see the need for them.

Why is there so much blame being thrown around today? Its fucking stupid! They tell you that smoking causes cancer, President Bush single-handedly ruined out country, the U.S. caused all the violence in Iraq. Sure, there are things that link them...but they are not the only causes.

Plus, I always get these fucking evolution people preaching their shit to me which includes the "survival of the fittest" shit. Now, we are fit, and they are yelling at us for it. If something else becomes "fit" and destroys us then so be it. Well, if some of this shit doesn't evolve and dies off because of that is that my fucking problem? I am not going to wait around for anything to evolve and I won't wait around for some god to help shit out. I was born...I am not living my life like I want to...and I will die.

I really want to know why we spend so much money on these experiment when...fuck anything could happen. We cannot count the ways in which our demise could be brought about by things NOT made by us. Who cares? Stop blaming shit and just go on with life. Turn this money toward a better cause that could help shit. What the hell can we really do about it anyways?

Ah...sorry but I have this humanities class and for some reason this book and the teacher insist that humanity is evil and worthless. It is so fucking depressing! My teacher shoudl put on some Nirvana and buy a shotgun so he can...(finish the sentence yourself)...

I am praying to every god and tree and animal out there that some black hole floats over to us and swallows us...

[Nightgaunt]

This idea that humanity is evil and destroying the earth is so pervasive for one core reason: it benefits the rich and powerful. Wait til Obama institutes his carbon taxes and "eco-squads" and then just follow the money. The only entities that are going to benefit from carbon dioxide being declared a toxin will be the Federal Reserve and the politicians that are paid to play along. The sooner we get hip to the fact that this is propaganda rather than science, the better.

Why shouldn't it bother anyone? Hell, people are spending so much time and money on shit just to make some short film on the discovery channel that ends with doom like music and a speech about how if we don't stop now it will only get worse. Well, unless I have damn hard evidence that things need to change because they will cause something to happen I see no point in spending so much of my time and my money changing to things that someone else says will help.

I know people say this alot but if all these important people really do care this much about the earth they will lead by example. But no they never do. They keep their houses and cars, their jets and their boats. They purchase these "earth friendly" products and when I look up what they cost, I shit a brick. When I look up how much more efficient they are than conventional systems I fail to see the need for them.

Why is there so much blame being thrown around today? Its fucking stupid! They tell you that smoking causes cancer, President Bush single-handedly ruined out country, the U.S. caused all the violence in Iraq. Sure, there are things that link them...but they are not the only causes.

Plus, I always get these fucking evolution people preaching their shit to me which includes the "survival of the fittest" shit. Now, we are fit, and they are yelling at us for it. If something else becomes "fit" and destroys us then so be it. Well, if some of this shit doesn't evolve and dies off because of that is that my fucking problem? I am not going to wait around for anything to evolve and I won't wait around for some god to help shit out. I was born...I am not living my life like I want to...and I will die.

I really want to know why we spend so much money on these experiment when...fuck anything could happen. We cannot count the ways in which our demise could be brought about by things NOT made by us. Who cares? Stop blaming shit and just go on with life. Turn this money toward a better cause that could help shit. What the hell can we really do about it anyways?

Ah...sorry but I have this humanities class and for some reason this book and the teacher insist that humanity is evil and worthless. It is so fucking depressing! My teacher shoudl put on some Nirvana and buy a shotgun so he can...(finish the sentence yourself)...

I am praying to every god and tree and animal out there that some black hole floats over to us and swallows us...

[Gaf The Horse With Tears]

Actually, it doesn't. The longer piece (containing your selected sections in bold) makes no such claim; indeed, a part that wasn't emphasized draws a "last straw" scenario.

I want to ask you something: what is it about the idea/theory of prehistoric-human-caused extinctions that bothers you?

I didn't say it proves, I said it "goes toward proving". It also says that if this event had not taken place, in all likelihood, we would still have Mammoths walking around... which to me translates into Humans did not cause the extinction.

What bothers me about it? The egotistical mindset that it takes to buy it. I don't believe that humans are the root cause of all the "bad" that has happened in the world. I don't think that we are a strong enough force to, so to speak, to move mountains and tear down the sky.

I think that humans are blamed for far more than their share of the ecosystems woes. We are a power player in the game of life played on this planet, but I also know that the power players in the Universe actually have little affect on the whole game. It's the little players that have the greater affect.. the ones that work with subtlety.

A super nova is one of the most powerful things in the Universe, but has little affect on anything not in it's immediate area... Gravity, the weakest of natural forces, can be felt and measured light years away.

My point is, blaming humans is the easy route to take and makes a shit load of money for certain humans along the way.

[Rev.Reverence]

I've never bought that humans caused the Mammoths to go extinct. There has never been any proof of it, just conjecture based solely on the fact that early humans lived at the same that Mammoths went extinct.

...you know...neither have I...it's that the Clovis peoples (& their descendants) were known for utilizing ALL the meat/parts of an animal...& for being mindful of thinning the herds to much...

...peoples all over the world used to be wiser than they have been in resent history...I find.

[Simon Bar Sinister]

I didn't say it proves, I said it "goes toward proving". It also says that if this event had not taken place, in all likelihood, we would still have Mammoths walking around... which to me translates into Humans did not cause the extinction.

What bothers me about it? The egotistical mindset that it takes to buy it. I don't believe that humans are the root cause of all the "bad" that has happened in the world. I don't think that we are a strong enough force to, so to speak, to move mountains and tear down the sky.

I think that humans are blamed for far more than their share of the ecosystems woes. We are a power player in the game of life played on this planet, but I also know that the power players in the Universe actually have little affect on the whole game. It's the little players that have the greater affect.. the ones that work with subtlety.

A super nova is one of the most powerful things in the Universe, but has little affect on anything not in it's immediate area... Gravity, the weakest of natural forces, can be felt and measured light years away.

My point is, blaming humans is the easy route to take and makes a shit load of money for certain humans along the way.

Passenger pigeon? Plains bison? Yes, I know we didn't totally wipe the Bison out, but we reduced them from tens of millions to a few thousand in a matter of a few decades.

As far as the theory espoused in the topic, you want to know what my main problem with it is? Let's say that this is proven true at some point and that humans weren't responsible for the extinction of the large land mammals in North America. What about South America, which man didn't reach in any appreciable numbers for at least 1,000 years after reaching NA? What about Australia, which (I think) saw humans arriving 10,000 years earlier? The expansion/settlement of Asia starting in the Caucusus and then moving eastward? Swarms of comets every time?

Side note: ever hear of the Tunguska explosion (which is what this theory reminds me of)? I was reading Scientific American a couple of months ago, and they had news of an expedition which is going to try to retrieve a possible piece of the asteroid/comet that caused it. Seems there's a lake there that wasn't on the pre-event maps...and they're going to drag the waters, as it were. Supposed to happen this summer.

[Rev.Reverence]

Passenger pigeon? Plains bison? Yes, I know we didn't totally wipe the Bison out, but we reduced them from tens of millions to a few thousand in a matter of a few decades.

As far as the theory espoused in the topic, you want to know what my main problem with it is? Let's say that this is proven true at some point and that humans weren't responsible for the extinction of the large land mammals in North America. What about South America, which man didn't reach in any appreciable numbers for at least 1,000 years after reaching NA? What about Australia, which (I think) saw humans arriving 10,000 years earlier? The expansion/settlement of Asia starting in the Caucusus and then moving eastward? Swarms of comets every time?

Side note: ever hear of the Tunguska explosion (which is what this theory reminds me of)? I was reading Scientific American a couple of months ago, and they had news of an expedition which is going to try to retrieve a possible piece of the asteroid/comet that caused it. Seems there's a lake there that wasn't on the pre-event maps...and they're going to drag the waters, as it were. Supposed to happen this summer.

...there are an awful lot of rocks (big rocks) flying around the Sun with us you know...just sayin'...

[Simon Bar Sinister]

...there are an awful lot of rocks (big rocks) flying around the Sun with us you know...just sayin'...

...and they just happen to hit just after humans show up?

Guess I won't try to move to some future moonbase after all!

[Rev.Reverence]

...and they just happen to hit just after humans show up?

Guess I won't try to move to some future moonbase after all!

No..silly..they're always hittin' everything!

...the science book told me so in like 3rd grade...

[Gaf The Horse With Tears]

I am not saying that humans have not caused the extinction of any animals, just not as many as some like to claim.

As for South America and the others you mentioned... Which animals are you refering too? The other large mamnals that went exint at the same time as Mammoths? The Saber Tooth? The Giant Ground Sloth? They went exinct at the same time as the Mammoths. The Tasmanian Tiger? Went exinct execpt on the island of Tasmania thousands of years before man settled the island. The Cave Lion? Went extinct during an ice age.

On your side note: Thats a mystery I would love to see solved.

[paradox]

...and they just happen to hit just after humans show up?

Guess I won't try to move to some future moonbase after all!

with the breathing room of a couple hundred to a couple thousand years, give or take, yea.

carbon dating is not exact or terribly accurate science.

[torn asunder]

Side note: ever hear of the Tunguska explosion (which is what this theory reminds me of)? I was reading Scientific American a couple of months ago, and they had news of an expedition which is going to try to retrieve a possible piece of the asteroid/comet that caused it. Seems there's a lake there that wasn't on the pre-event maps...and they're going to drag the waters, as it were. Supposed to happen this summer.

i can't believe you don't know that the tunguska explosion wasn't a meteor/comet/etc, it was nikola tesla's "death-ray" before he had perfected the calibration of locations. it's part of what his "wireless world" idea was about. don't you read anything!?

(and i'm only half-kidding!)