About 450 million years ago, Earth suffered the second-largest mass extinction in its history

A team at CalTech is using new methods to try and solve the mystery of the 2nd largest mass extinction in history. This is their press release on the research.

7thspa ce.com


About 450 million years ago, Earth suffered the second-largest mass extinction in its history—the Late Ordovician mass extinction, during which more than 75 percent of marine species died. Exactly what caused this tremendous loss in biodiversity remains a mystery, but now a team led by researchers at the California Institute of Technology (Caltech) has discovered new details supporting the idea that the mass extinction was linked to a cooling climate.

"While it's been known for a long time that the mass extinction is intimately tied to climate change, the precise mechanism is unclear," says Seth Finnegan, a postdoctoral researcher at Caltech and the first author of the paper published online in Science on January 27. The mass extinction coincided with a glacial period, during which global temperatures cooled and the planet saw a marked increase in glaciers. At this time, North America was on the equator, while most of the other continents formed a supercontinent known as Gondwana that stretched from the equator to the South Pole.

I am no expert in this type of research but thought some of the members would like to have a look at this release.



another source that has some images, to include a period map..

www.astrobio.net...

Thanks for the info.. which I find interesting as it reminded me of the little I knew about these mass extinction level events being part of earth's long lifecycle

reply to post by JacKatMtn

I subscribed to this thread a couple of days ago, but it doesn't look like you're getting many takers.

Yes, of course climate change is the only possible cause of such worldwide extinctions. The trigger for change may vary (asteroid impact, massive vulcanism, funny things happening to the Sun, humans pouring megatonnes of greenhouse gases into the atmosphere) but the only way the impact of anything is going to be worldwide is through climate change. That is because the vectors of extinction, whatever they are, can only be carried worldwide through the oceans or the atmosphere – and changes to ocean and atmosphere are precisely what we call 'climate'.

Would a supervolcano have that effect on marine life though? Maybe a mass belching of methane from the ocean??

Maybe a mass belching from Al Gore?

Originally posted by HoldTheBeans
Would a supervolcano have that effect on marine life though? Maybe a mass belching of methane from the ocean??

I would assume that a covering of the atmosphere by a large cloud, would have had more impact.

Originally posted by HoldTheBeans
Would a supervolcano have that effect on marine life though? Maybe a mass belching of methane from the ocean??

Maybe a mass belching from Al Gore?

Does the term "nuclear winter" mean anything to you?
Or is that something else you dismiss as hype because you don't like someone who has talked about it?

A super volcano erupting effects things worldwide by blocking out the sun's rays. It's just the same as a nuclear winter. Without sunlight, photosynthesis doesn't happen. Much life in the sea, just like that on land, is directly or indirectly dependant on photosynthesis. Without sufficient light you don't have phytoplankton, and the food-chain collapses.

Originally posted by Kailassa

Originally posted by HoldTheBeans
Would a supervolcano have that effect on marine life though? Maybe a mass belching of methane from the ocean??

Maybe a mass belching from Al Gore?

Does the term "nuclear winter" mean anything to you?
Or is that something else you dismiss as hype because you don't like someone who has talked about it?

A super volcano erupting effects things worldwide by blocking out the sun's rays. It's just the same as a nuclear winter. Without sunlight, photosynthesis doesn't happen. Much life in the sea, just like that on land, is directly or indirectly dependant on photosynthesis. Without sufficient light you don't have phytoplankton, and the food-chain collapses.

It's not the same as a nuclear winter. Maybe your hero Al Gore can instruct you with one of his powerpoint presentations on the differences. Of course he's probably too busy buzzing around in his private jet spewing greenhouse gasses all over the place. lol

reply to post by JacKatMtn


Seems like another crash or impact as they are now called. Would be amazing if there was a craft 1/4 the dia. of EA cresent shaped stuck deep in the crust STILL!!!!

Originally posted by HoldTheBeans

It's not the same as a nuclear winter. Maybe your hero Al Gore can instruct you with one of his powerpoint presentations on the differences. Of course he's probably too busy buzzing around in his private jet spewing greenhouse gasses all over the place. lol

Would you like to explain the difference, in regard to the world-wide effect on life, between a nuclear winter and a super volcano eruption? It's not my field of study, and I'd be delighted if you could teach me something.

Why do you assume Al Gore is my hero, and why do you keep bringing him up in a thread which has nothing to do with him? It seems he is of much greater importance to you than he is to me.

Originally posted by Kailassa

Originally posted by HoldTheBeans

It's not the same as a nuclear winter. Maybe your hero Al Gore can instruct you with one of his powerpoint presentations on the differences. Of course he's probably too busy buzzing around in his private jet spewing greenhouse gasses all over the place. lol

Would you like to explain the difference, in regard to the world-wide effect on life, between a nuclear winter and a super volcano eruption? It's not my field of study, and I'd be delighted if you could teach me something.

Why do you assume Al Gore is my hero, and why do you keep bringing him up in a thread which has nothing to do with him? It seems he is of much greater importance to you than he is to me.

edit on 3/2/11 by Kailassa because: (no reason given)

Google it. If you can't do that then maybe Al Gore can fill you in.

reply to post by HoldTheBeans


They are fundamentally the same thing. Both a super volcano and a nuclear winter would throw up particles into the air, causing less sunlight to reach the surface of the earth.

Also, telling someone to use Google when they ask you a question is not an appropriate response. It's on you to provide evidence for your claim.

reply to post by PieKeeper

Thanks PieKeeper.
I had googled both and the effects, apart from a few chemicals, seemed the same, both causing extinctions by airborne particles blocking heat and sunlight, so I was wondering what I was missing.

I'm still puzzled why he keeps bringing up the name of Gore, someone I've never quoted or posted about, in a thread in which Gore has no relevance. I guess it's just a case of obsession.