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Old 04-10-2012, 06:03 PM
 
Location: Wasilla, Alaska
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Quote:
Originally Posted by 6 Foot 3 View Post
You just have to research it as there's plenty of articles supporting the hypothesis of an shattering comet impacting North America around 12,900 years ago.
That is what I have read as well, but only effecting the North American continent. The exploding comet hypothesis at the beginning of the Younger Dryas has also been suggested as the cause for the Clovis Man extinction event in North America.

I do not believe there was one decisive event that caused the extinction of the megafauna. I think there were several issues, including a dramatic change in the climate.

I also find it difficult to believe that the megafauna were hunted to extinction. There were not that many humans 11,000 years ago. It is far more likely that climate played the major role in their extinction.
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Old 04-10-2012, 06:34 PM
 
Location: Texas
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Originally Posted by Glitch View Post
That is what I have read as well, but only effecting the North American continent. The exploding comet hypothesis at the beginning of the Younger Dryas has also been suggested as the cause for the Clovis Man extinction event in North America.

I do not believe there was one decisive event that caused the extinction of the megafauna. I think there were several issues, including a dramatic change in the climate.

I also find it difficult to believe that the megafauna were hunted to extinction. There were not that many humans 11,000 years ago. It is far more likely that climate played the major role in their extinction.
I remember reading an era when pretty much everything lived, died off, as in frozen. Just looking it up, it was called "Snowball Earth".
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Old 04-10-2012, 08:08 PM
 
Location: Wasilla, Alaska
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Originally Posted by Brian.Pearson View Post
I remember reading an era when pretty much everything lived, died off, as in frozen. Just looking it up, it was called "Snowball Earth".
That was some 650 million years ago, before there was multi-cellular life. It was during the Cambrian Period, just after the "snowball earth," that multi-cellular life prospered and multiplied. Some think the "snowball earth" may have been the cause for the spurt of growth and evolution that followed.

The biggest extinction event, however, was the Permian-Triasic extinction event 252.28 million years ago, also known as "The Great Dying." Where 96% of all marine life, and 70% of all land critters became extinct. Most attribute this extinction event to an asteroid impact, but that is somewhat controversial. Since Earth's crust is recycled every 220 million years or so, it is not likely that they will find a crater.
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Old 04-10-2012, 08:51 PM
 
Location: Texas
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Yep, I can see how various critters can survive and others can be die.
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Old 04-10-2012, 09:27 PM
 
Location: Wasilla, Alaska
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99.999999% of every critter that has ever lived is now extinct. Our days are numbered.

It should also be noted that critters go extinct all the time, not just during mass extinction events. Additionally, we are talking about geological time periods. A mass extinction event could be over a 1,000, 10,000, or even a 100,000 year time span. Those time periods are virtually instantaneous when we are talking in epochs involving millions of years.
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Old 04-11-2012, 06:33 AM
 
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Originally Posted by Glitch View Post
That is what I have read as well, but only effecting the North American continent. The exploding comet hypothesis at the beginning of the Younger Dryas has also been suggested as the cause for the Clovis Man extinction event in North America.
Yeap it mainly effected just North America however it did also bring about a re-cooling of Europe as well and yeap i've stated before about how ''Clovis Points'' disappeared at that moment as well.

Quote:
Originally Posted by Glitch View Post
I do not believe there was one decisive event that caused the extinction of the megafauna. I think there were several issues, including a dramatic change in the climate.
There are other scientists who don't believe in this as well with physicist Mark Boslough being the major opponent (no impact crater, overkill theory etc.) however i do subscribe to that event happening as the evidence is very clear at least to myself.

Firstly at that exact moment geologically 35 types of North American fauna including Clovis Man just disappears and if it was just do to ''overkill'' then that should have taken centuries for the fauna to slowly disappear.. Secondly when they dig down to the Younger Dryas Boundary whether in the earthen ground or in the Greenland ice core they find unsually high levels of Iridium as well as the hexagonal nanodiamonds which only happens when an large projectile impact has occured. Thirdly just looking at the ''Black Mat'' which is at the exact boundary of when this ''hypothesized'' event happened is found at some 65 locations all around the western United States show that something very powerful and of intense heat scorched the continent's surface and so killed off most of what was residing on the surface (fauna, plants and man etc.).

Here's a Black Mat sample in Arizona. Something very hot and powerful created that geological imprint at the 12,900 boundary.


Last edited by Six Foot Three; 04-11-2012 at 06:44 AM..
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Old 04-11-2012, 07:45 AM
 
Location: Texas
5,069 posts, read 5,697,389 times
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Quote:
Originally Posted by Glitch View Post
99.999999% of every critter that has ever lived is now extinct. Our days are numbered.

It should also be noted that critters go extinct all the time, not just during mass extinction events. Additionally, we are talking about geological time periods. A mass extinction event could be over a 1,000, 10,000, or even a 100,000 year time span. Those time periods are virtually instantaneous when we are talking in epochs involving millions of years.
It could be that a few of those have adapted to the point that they are different animals or plants.
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Old 04-11-2012, 08:19 AM
 
Location: Wasilla, Alaska
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Quote:
Originally Posted by 6 Foot 3 View Post
Yeap it mainly effected just North America however it did also bring about a re-cooling of Europe as well and yeap i've stated before about how ''Clovis Points'' disappeared at that moment as well.

There are other scientists who don't believe in this as well with physicist Mark Boslough being the major opponent (no impact crater, overkill theory etc.) however i do subscribe to that event happening as the evidence is very clear at least to myself.

Firstly at that exact moment geologically 35 types of North American fauna including Clovis Man just disappears and if it was just do to ''overkill'' then that should have taken centuries for the fauna to slowly disappear.. Secondly when they dig down to the Younger Dryas Boundary whether in the earthen ground or in the Greenland ice core they find unsually high levels of Iridium as well as the hexagonal nanodiamonds which only happens when an large projectile impact has occured. Thirdly just looking at the ''Black Mat'' which is at the exact boundary of when this ''hypothesized'' event happened is found at some 65 locations all around the western United States show that something very powerful and of intense heat scorched the continent's surface and so killed off most of what was residing on the surface (fauna, plants and man etc.).

Here's a Black Mat sample in Arizona. Something very hot and powerful created that geological imprint at the 12,900 boundary.
There is sufficient evidence to convince me that something catastrophic occurred on the North American continent 12,900 years ago, but that would not explain the mass extinction of the megafauna world-wide. Mammoths did not exist solely in North America. Europe's wooly rhino, mammoths, Irish Elk, cave bears and cave lions, the Australian Moa, Smilodon in South America, and other megafauna around the planet became extinct around the same time.

This leads me to believe that there were several problems occurring roughly at the same time. Perhaps the soot in the atmosphere from a continent being on fire may have caused global cooling for a few years, which may have triggered other climatic changes and temporarily disrupted the food-chain. I am only speculating of course, but it seems highly improbable to me that a single event can be attributed to the extinction of the megafauna.
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Old 04-11-2012, 08:28 AM
 
Location: Wasilla, Alaska
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Originally Posted by Brian.Pearson View Post
It could be that a few of those have adapted to the point that they are different animals or plants.
Some have not changed at all, except in size. Scorpions, and other arthropods, for example, have been around since the Ordovician period some 488 million years ago. If only we could be so lucky.

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Old 04-15-2012, 10:04 PM
 
Location: Andersonville, Chicago
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Originally Posted by legalsea View Post
Remember: Jesus blessed the dinosaurs, too:

Good thing that was not a T-Rex standing behind JC !
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