Date: 23/10/2014 02:41:32
From: PermeateFree
ID: 613955
Subject: Wonders of the Ediacaran

Hope it is sciencey enough for you.

>>So far, says Gehling, about 60 genera and a couple of hundred species of Ediacara flora and fauna have been found on every continent except Antarctica. They have very distinctive patterns, some of which are similar to those of Cambrian fossils.

“Others look like nothing we’ve seen since,” he says.

Many appear to be quite flat, shaped like leaves, fronds or mats. This could be because they were indeed flat — maximising their surface area and the amount of oxygen and nutrients they could absorb from seawater.
But it could also be the case that their soft body did not allow their three dimensional shape to be preserved, says Gehling.

Some scientists have characterised Ediacaran fossils as failed experiments in multicellular life but Gehling rejects this idea.

“I particularly hate that phrase,” he says.

Gehling points to Dickensonia — the creature first identified by Sprigg — found in multiple fossil beds throughout the Flinders Ranges as well as in Russia.

“They were enormously successful by any measure in the sense there must have been billions of them in the ocean in the Ediacaran,” says Gehling.

Yes they went extinct, he says, but that’s no reason to write them off.
“You wouldn’t call dinosaurs a failed experiment,” says Gehling.

http://www.abc.net.au/science/photos/2014/10/22/4109389.htm

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Date: 23/10/2014 02:51:09
From: roughbarked
ID: 613956
Subject: re: Wonders of the Ediacaran

Yes. The Ediacaran is fascinating.

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Date: 24/10/2014 20:01:06
From: mollwollfumble
ID: 615255
Subject: re: Wonders of the Ediacaran

> So far, says Gehling, about 60 genera and a couple of hundred species of Ediacara flora and fauna have been found on every continent except Antarctica. They have very distinctive patterns, some of which are similar to those of Cambrian fossils.

I dispute that similarity of pattern has any evolutionary significance here. Practically nothing from the Ediacaran fauna (I wouldn’t call it flora) survived into the Cambrian. Any resemblances, such as between the Ediacaran Charnia and modern Sea Pens, is purely coincidental and has nothing to do with evolutionary lineages.

The end of the Ediacaran saw a major extinction event. Wikipedia has “very few organisms are known from both sides of the Ediacaran-Cambrian boundary. One such organism is the agglutinated foramanifera Platysolenites.”

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Date: 24/10/2014 20:11:04
From: mollwollfumble
ID: 615260
Subject: re: Wonders of the Ediacaran

> 60 genera

What are they?

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Date: 24/10/2014 21:09:46
From: PermeateFree
ID: 615320
Subject: re: Wonders of the Ediacaran

mollwollfumble said:


> So far, says Gehling, about 60 genera and a couple of hundred species of Ediacara flora and fauna have been found on every continent except Antarctica. They have very distinctive patterns, some of which are similar to those of Cambrian fossils.

I dispute that similarity of pattern has any evolutionary significance here. Practically nothing from the Ediacaran fauna (I wouldn’t call it flora) survived into the Cambrian. Any resemblances, such as between the Ediacaran Charnia and modern Sea Pens, is purely coincidental and has nothing to do with evolutionary lineages.

The end of the Ediacaran saw a major extinction event. Wikipedia has “very few organisms are known from both sides of the Ediacaran-Cambrian boundary. One such organism is the agglutinated foramanifera Platysolenites.”

It does say SIMILAR mollwollfumble, NOT the same.

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Date: 24/10/2014 21:11:44
From: PermeateFree
ID: 615325
Subject: re: Wonders of the Ediacaran

mollwollfumble said:


> 60 genera

What are they?

:)))

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