New research reveals that it took some 10 million years for Earth to recover from the greatest mass extinction of all time, some 250 million years ago. (Credit: © byheaven / Fotolia)
Posted on 05/28/2012 7:25:47 PM PDT by SunkenCiv
It took some 10 million years for Earth to recover from the greatest mass extinction of all time, latest research has revealed.
Life was nearly wiped out 250 million years ago, with only 10 per cent of plants and animals surviving. It is currently much debated how life recovered from this cataclysm, whether quickly or slowly.
Recent evidence for a rapid bounce-back is evaluated in a new review article by Dr Zhong-Qiang Chen, from the China University of Geosciences in Wuhan, and Professor Michael Benton from the University of Bristol. They find that recovery from the crisis lasted some 10 million years, as explained May 27 in Nature Geoscience.
There were apparently two reasons for the delay, the sheer intensity of the crisis, and continuing grim conditions on Earth after the first wave of extinction.
The end-Permian crisis, by far the most dramatic biological crisis to affect life on Earth, was triggered by a number of physical environmental shocks -- global warming, acid rain, ocean acidification and ocean anoxia. These were enough to kill off 90 per cent of living things on land and in the sea.
Dr Chen said: "It is hard to imagine how so much of life could have been killed, but there is no doubt from some of the fantastic rock sections in China and elsewhere round the world that this was the biggest crisis ever faced by life."
Current research shows that the grim conditions continued in bursts for some five to six million years after the initial crisis, with repeated carbon and oxygen crises, warming and other ill effects.
(Excerpt) Read more at sciencedaily.com ...
New research reveals that it took some 10 million years for Earth to recover from the greatest mass extinction of all time, some 250 million years ago. (Credit: © byheaven / Fotolia)
Meteor May Have Started Dinosaur EraIn the layer of rock corresponding to the extinction, the scientists found elevated amounts of the rare element iridium. A precious metal belonging to the platinum group of elements, iridium is more abundant in meteorites than in rocks on Earth. A similar spike of iridium in 65 million-year-old rocks gave rise in the 1970's to the theory that a meteor caused the demise of the dinosaurs... The levels are only about one-tenth as high as those found at the later extinction. That could mean that the meteor was smaller or contained less iridium... In the same rock layer, Dr. Olsen and his colleagues found a high concentration of fern spores -- considered an indicator of a major disruption in the environment. Because spores carried by the wind can travel long distances, ferns are often the first plants to return to a devastated landscape. The scientists found more evidence of rapid extinction in a database of 10,000 muddy footprints turned to rock in former lake basins from Virginia to Nova Scotia... Because the sediment piles up quickly in lake basins, the researchers were able to assign a date to each footprint, based on the layer of rock where it was found. They determined that the mix of animals walking across what is now the East Coast of North America changed suddenly about 200 million years ago. The tracks of several major reptile groups continue almost up to the layer of rock marking the end of the Triassic geologic period 202 million years ago, then vanish in younger layers from the Jurassic period...
by Kenneth Chang
May 17, 2002
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| GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach | |
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The article is gradualist / global warming nonsense. |
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We will need almost as long to recover from an obozo 2nd term.
Good thing they destroyed all those SUVs. Damn things always cause global temperatures to go up 10 degrees F every year, with only 1000 on the road.
(I shouldn’t need /sarc)
The article is gradualist / global warming nonsense.
Yeah, damn all those hippy, pinko-commie, running dog scientists. Everyone in their right minds know there was no life on earth prior to 10 thousand years ago.
There’s been recovery from each of the mass extinctions — otherwise we wouldn’t be here, our ancestors having died — but this study is just gradualist nonsense. The P-T boundary is narrow like the K-T boundary, has iridium (which is not as strong as at the K-T boundary, but much stronger than volcanism can produce), and whole taxa just stopped at the boundary, no “five or six milllion year” period BS as in the article.
global warming, acid rain, ocean acidification and ocean anoxiaand don't forget, my ass.
“The end-Permian crisis, by far the most dramatic biological crisis to affect life on Earth, was triggered by a number of physical environmental shocks — global warming, acid rain, ocean acidification and ocean anoxia.”
Not to mention SUV-driving dinosaurs smoking cigarettes.
Al Gore ... is that you?
Flash Recovery Of Ammonoids After Most Massive Extinction Of All Time
ScienceDaily
Sep. 2, 2009
http://www.sciencedaily.com/releases/2009/09/090902122331.htm
Asteroid ‘destroyed life 250m years ago’
http://www.freerepublic.com/focus/chat/2084610/posts
New Ancient Fungus Finding Suggests World’s Forests Were Wiped Out In Global Catastrophe
http://www.freerepublic.com/focus/chat/2358035/posts
New Fossils Suggest Ancient Cat-sized Reptiles in Antarctica
LiveScience.com on Yahoo | 6/7/08 | Jeanna Bryner
Posted on 06/07/2008 7:53:24 PM PDT by NormsRevenge
http://www.freerepublic.com/focus/news/2027763/posts
"The planet has been through a lot worse than us. Been through earthquakes, volcanoes, plate tectonics, continental drift, solar flares, sun spots, magnetic storms, the magnetic reversal of the poles … hundreds of thousands of years of bombardment by comets and asteroids and meteors, worldwide floods, tidal waves, worldwide fires, erosion, cosmic rays, recurring ice ages … And we think some plastic bags and some aluminum cans are going to make a difference? The planet isn’t going anywhere. WE are! "
- George Carlin
>>Good thing they destroyed all those SUVs. Damn things always cause global temperatures to go up 10 degrees F every year, with only 1000 on the road.
<<
Too bad the dinosaurs couldn’t stop farting (seriously, that is the new “theory” on why they died).
My theory:
The dinosaurs did not burn fossil fuels, and that is what indirectly killed them. They had a “Mega - Surplus”.
Massive oceans of Oil were set ablaze when the earth was hit by a meteor. Billions of barrels of oil splashed for miles.
But as luck would have it, there was no FEMA agency to rescue them and contain the spill. There was no “Sean Penn” dinosaur yet evolved that could save the day and put out the fires.
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