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Darrrius
2005-Jul-12, 02:54 PM
Link to a bbc story about discoveries in China, namely half a billion year old fossil remains of a creature that lived on the ocean floor before the cambrian explosion.

http://news.bbc.co.uk/1/hi/sci/tech/4664741.stm

lswinford
2005-Aug-02, 08:51 PM
Thanks for the link. I sometimes look at that site but missed this page. As for the "lying flat", I bet not. Branching organisms rarely work only in 2 dimensions, especially in the bouyant environment of water.

cran
2005-Aug-07, 09:47 AM
I'm a little tempted to take that bet, lswinford; the article referred more than once to the fossil's similarities to lichen and fungi, suggesting it was more likely a colonial life, rather than a discrete organism, much like the algal mats that form stromatolites (which had been around for quite some time before this example).

And, given that some 'buoyant' branching forms of Ediacaran life were already known, I'm willing to bet that it was a reasonably well considered opinion on the part of the discoverers who, had more than a little digital image to work from - we can study fossils at very large magnification these days.

The stunning thing about the Ediacaran fossils is the quality of preservation of the soft bodies, in so many diverse locations...and not one shell, or bone, or hard plate has been found among them!

Then they simply disappear (in percentage terms, the greatest mass extinction of all, almost 100% of mesoscopic life!), and the Cambrian explosion just seems to take over (apparently without the usual 10+ My recovery period!).

In many ways, the emergence of Ediacaran fauna, and the 'sudden' (geologically-speaking) extinction/transition to shelled or plated invertebrates is a bigger mystery than the P/T or K/T mass extinctions.

So, how much did you want to bet? ;)

jkmccrann
2005-Dec-13, 05:04 PM
It is interesting to hear of any discoveries of Pre-Cambrian life because its certainly a period we don't know much about.