Posted on 05/10/2002 1:01:25 AM PDT by Gladwin
Fossils in rocks deposited 1.2 billion years ago could be the oldest evidence of animal life discovered so far. Australian researchers believe a worm-like creature left a trail in sandstone found off the western tip of Australia.
If confirmed, it would be the oldest example of an animal comprised of more than one cell.
Until now, it was thought that multicellular animals, or metazoans, only appeared about 600 million years ago.
The rocks in question come from the Stirling Range Formation of south-western Australia.
Fine ridges in the sandstone may be "casts of mucus-impregnated strings of sediment left by an organism creeping over the surface," say Dr Birger Rasmussen and colleagues of the University of Western Australia.
The fossilised worm cast gives a glimpse into a primordial world.
At the time, it was thought to be inhabited largely by microbes and algae.
According to current theory, there was a sudden burst of animal life about 600 million years ago.
This event - the Cambrian explosion - is clearly recorded in the fossil record.
There is little undisputed evidence of animal life before then, so the Australian research could prove contentious.
If the dating studies are correct, scientists will have to explain why little changed on Earth for millions of years after the arrival of primitive animals.
The fossil evidence is revealed in the journal Science.
I'm reading a mainstream geology test now, and I broke out laughing when I saw the explanation for items like this.
We are told that sedimentary rock (like sandstone) was formed by lots pressure over lots of years on material not originally rock.
So here were some worms burrowing through that not originally rock material leaving their little tunnels a zillion years ago. And then comes all this pressure that can compact mud into stone but it leaves the little worm tunnels alone. And all that time that fogs over what really happened, but I would guess that we cannot find two year-old worm tunnels now.
ML/NJ
Interesting question. I wonder if anyone at FR has the answer.
Gee. What a swell suggestion!
But I can't do it because I have to pay for my kids to go to college now.
The text I referred to in my post is one that I picked up at the University of Virginia. I assume they use it for their introductory geology class, and I am reading it. There are absuridities like the one I pointed out here on almost every page.
For the record I believe that these things are called "Bioturbation Structures." The one they referred to in the article may be the "oldest" for now but it is hardly unique.
ML/NJ
I have read that there is genetic evidence that the divergence actually took maybe a half billion years earlier. The Cambrian explosion would then be a sudden burst of fossilization. If true, it's still mysterious but it's a different mystery.
The worm holes/tunnels were filled up with other (dis-similar) material prior to compression. Simple.
The NJ in ML/NJ is supposed to be a clue to where I live. I assure you that I could teach most science courses given at most junior colleges that I know about, if I wanted to.
Instead of suggesting how I could enhance my education, why don't you address the question I posed?
ML/NJ
What other material?
Where did it come from?
Where did it go to?
Why don't we observe tunnels filling up with dissimilar materials today? (leaving aside my cigar butts which sometimes find their way into the holes some animal make in my backyard)
ML/NJ
You may not care about your online "reputation" like you care about your in-real-life reputation, and it shows. You're just being nasty.
I, by the way, am *both* a creationist *and* an adherent to the scientific process. Good, honest science is perfectly compatible with biblical creationism.
Please don't respond with nastiness to me, Allend, as you've done toward other posters. (By the way, in case you want to start an ad hominem attack, I have earned 2 master's degrees and 2 bachelor's degrees; that's ultimately very irrelevant, but that might stem off your personal attack on me.)
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