Re: ILLogical Evolution

Susan Brassfield (
Tue, 31 Aug 1999 16:39:50 -0600

>Cliff Lundberg wrote:
>>>It doesn't matter at all how few these first known vertebrates
>>>were (if they really were few, in number of species or of individuals). Nor
>>>does it matter in the least that they were small, or that they were fish.

>Susan B wrote:
>>oh, but it does. The most highly relevant word in my paragraph above is
>>"only." All the cordata present were ONLY fish.

Cliff Lundberg wrote:
>You seem to think the origin of the chordata was a trivial event compared
>to the evolution of tetrapods etc from fish.

I do seem to think that don't I? I've had similar arguments with people
about abiogenesis. Somehow it is thought that you have to know where
someone or something originated before you can study the history of that
life. And if you don't see the birth certificate, then that life hasn't
existed, or we can't know anything at all about them.

over the last 550 million years a lot of the traces of the earliest part of
life's history has been destroyed by the actions of the lives and geology
that have happened since then.

>>In the history of life, complexity sort of peaked early. I don't really see
>>how this helps the creationist case.
>I can't speak for the creationists, but I can't help noticing that their model
>involves a sudden origin of complexity followed by a stable level of
>complexity, so I guess they might be encouraged by your admission.

their "model" proposes that everthing--fish, birds, people, insects--was
created all at once ex nihilo. There is ample evidence that the Cambrian
was not that event. The bare fact that *anything* alive existed before the
Cambrian prevents the Cambrian "explosion" from being the creation event.

>The Cambrian boom will not be puzzled out, as long as anyone who mentions
>it is labeled a creationist. It's really more fun to think scientifically
>this mystery than to worry about helping the creationist case.

oh, did you think that the Cambrian was not being investigated? That it
would never be investigated without the creationists insisting upon it?
That nobody asks questions about it for fear of being labeled a
Creationist? :-) Think again.

a very quick search of the web ( yielded dozens of websites,
some more informative than others.

This one had a bit of interesting information:
"Approximately 544 million years ago, the supercontinent landmass broke into
pieces. This allowed for an explosion of animal life for several reasons:
1. The amount of continental shelf increased dramatically, providing a prime
environment for Cambrian life.
2. Animals developed hard parts (like shells) giving them protection from
predators. This also enhanced the fossil record because the hard
parts were
well preserved.
3. A new ecological niche appeared which animals adapted to well. "

here is a paper on very early cordates:

It looks like nobody bothered to mention to these people that you weren't
supposed to discuss the Cambrian for fear of being called a creationist!
"The word 'Cambrian' came from the Roman name for
Wales where the first geological studies were
conducted on the period's strata or layers of soil
where its fossils are found. It began 543 million years
ago and ended 43 million years later. The Cambrian
Period is also known as Biology's Big Bang and the
Cambrian Explosion because of its great diversity of
life. Here was the first appearance of limbs and
segmented bodies. The first organisms to be predators,
and to develop shells, jaws, claws, and teeth appeared
here as well. We see varied multicellular and complex
life that spent most of the time on the muddy sea
floor. No creatures traveled by land, all were aquatic.
It was during this time that ancestors of all animals
which fly, swim, and crawl evolved and appeared in
less than 10 million years; few new structural models
emerged from Cambrian bodies. But scientists
estimate that evolution requires 75 million years to
show change. 'Explosion' seems a fitting word to
describe the speed at which life evolved during the
Cambrian. "



"Life itself is the proper binge."
--Julia Child