Re: Cambrian Explosion

Susan Brassfield (susan-brassfield@ou.edu)
Thu, 1 Jul 1999 16:40:38 -0600

>Susan Brassfield wrote:
>
>>>>http://id-www.ucsb.edu/fscf/library/origins/quotes/cambrian.html
>
>>CL:
>>>The emphasis on Behe and ID on the other pages seems pretty
>>>creationistic. But the quotes are good.
>>
>>The quotes are NOT good.
>>the pictures and quotes are nearly identical with those found on the
>>Access Research Network website which is unabashedly creationist.
>
>This is not scientific criticism. The quotes are not from creationists,
>but from eminent evolutionists. Nor are the quotes unfairly cropped.

Darwin's quote was unfairly cropped. And I'm familiar with some of the
other quotes and they are also out of context. In the quote from Darwin, he
is definitely talking about the lack of pre-cambrian fossils. In the *very
next* quote. Eldridge is not talking about the Cambrian at all, but is
discussing punctuated equilibrium in general terms. That is not made clear.
In fact the obvious infrence we are supposed to draw is that they are
discussing the same topic. This is an unethical practice at best and at
worst, completely dishonest.

>Darwin saw the problem; but now, with the evidence in much sharper
>focus, Darwinists can't see any problem.

actually, modern biologists have a lot more evidence available than Darwin
did in his day and the evidence has proved him right.

>>the point of the pictures and quotes is to make it seem--to someone who
>>doesn't know much about earth's history--as if the Cambrian was the
>>creation event.
>
>The problem will not be solved by directing accusations of creationism
>at anyone who mentions the problem. I'm sorry, but the Cambrian
>explosion of phyla was a real event. Is it not obvious that the prior
>faunas could not have thrived if gnathostomes were about?

why not? Don't animals with and without jaws co-exist now? Of course they
do, and did then. The "problem" of the Cambrian exists only in the mind of
hopeful creationists. There are pre-Cambrian fossils that Darwin didn't
know about because they had not been discovered in his day.

>>"Consequently, if my theory be true, it is indisputable that before the
>>lowest
>>Silurian stratum was deposited, long periods elapsed, as long as, or probably
>>far longer than, the whole interval from the Silurian age to the present day;
>>and that during these vast, yet quite unknown, periods of time, the world
>>swarmed with living creatures. "
>>
>>He was, of course, correct. The tree has roots.
>
>All Earthly life has roots, all the way back to the origin of life. But where
>are the particular roots of the Cambrian fauna? The seemingly instantaneous
>origin of these forms does not fit the Darwinian model.

I think part of the trick is in the phrase "seemingly instantaneous." To
someone who knows nothing about the history of life, that sounds like it
could be a week (six days, anyway). Nowhere on the web site in question is
it pointed out that the "seemingly instantaneous" appearance of Cambrian
fauna took 65 million years. That's really fast for a geologist, but not
for the rest of us! Also nowhere on that website is it mentioned that
*none* of the Cambrian fauna appeared in their modern form. The UCSB
website gives the impression that there were Cambrian dogs, cats and
people--that everything appeared in the Cambrian and hasn't changed since.

this is from "An Introduction to Evolutionary Biology" in the talk.origins
archives:

"Animals start appearing prior to the Cambrian, about 600 million years ago.
The first animals dating from just before the Cambrian were found in rocks
near Adelaide, Australia. They are called the Ediacarian fauna and have
subsequently been found in other locales as well. It is unclear if these forms
have any surviving descendants. Some look a bit like Cnidarians (jellyfish,
sea anemones and the like); others resemble annelids (earthworms). All the
phyla (the second highest taxonomic category) of animals appeared around
the Cambrian. . . .

"Some paleontologists think more animal phyla were present then than now.
The animals of the Burgess shale are an example of Cambrian animal fossils.
These fossils, from Canada, show a bizarre array of creatures, some which
appear to have unique body plans unlike those seen in any living animals.

"The extent of the Cambrian explosion is often overstated. Although quick, the
Cambrian explosion is not instantaneous in geologic time. Also, there is
evidence of animal life prior to the Cambrian. In addition, although all the
phyla of animals came into being, these were not the modern forms we see
today. Our own phylum (which we share with other mammals, reptiles,
birds, amphibians and fish) was represented by a small, sliver-like thing
called Pikaia. Plants were not yet present. Photosynthetic protists and algae
were the bottom of the food chain. Following the Cambrian, the number of
marine families leveled off at a little less than 200."

The UCSB website is creationist propaganda.

Susan

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

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