>Re: Clarification of my Progressive Creationist position
>Wed, 28 Jun 95 21:24:48 EDT
>
>ABSTRACT: This post is over 100 lines long. It represents a shift in
>my position to a more consistent Progressive Creationist position. I
>discuss important evidence supporting the reptilian jawbones-mammalian
>earbones transition from Gould's "Eight Little Piggies". I now accept
>this transition as fact, although I do not accept it happened by a 100%
>natural process. If my personal intellectual journey is uninteresting
>to you then send this to the bit bucket without reading on! <g>
This was before my time on this list, but I'll respond to it now.
I'm an evolutionist and I don't accept this transition, nor do I accept
similar suggestions of Gould's such as that gill arches migrated to
form jaws.
>So Glenn is partly right. The "apologetical books" who keep repeating
>"how could an animal chew and hear while this was happening?", are
>ignoring the evidence.
The evidence may be interpreted differently. The big point that is routinely
ignored is that intermediate forms are not necessarily transitional; they
appear transitional only if one approaches the evidence already convinced
that such-and-such transition has occurred. Without this prejudice, homologies
are simply homologies, evidence of common ancestry. As an evolutionist who
is skeptical of much evolutionary theory, and who derives some consolation
from the objective criticisms made by creationists, it's disappointing to see
creationists buying in to unjustified assumptions like this. Well, Stephen's
changed his mind before, maybe he'll do so again.
A less presumptuous interpretation is the inference that the skeletal
structures
in question exhibit a morphological range, from the reptilian to the mammalian
form. Those at the mammalian end had the delicate highly reduced bones from
way back, and put them to use for hearing possibly even before becoming
terrestrial tetrapods. The reptilian lineages committed these bones to jaw
duty, and there they remained, big and strong. Some descendants of the
original lungfish progenitors fell in between in the morphology of these two
types; no problem.
The idea is that the major types were formed in the Cambrian explosion,
and quickly radiated into a variety of forms and niches, consistent with the
principle of 'early experimentation, later standardization'; subsequent
evolution was basically a shakeout of less optimal types, many of which
were intermediate in form between some of the surviving types. Thus you
get intermediates which were not transitional.
When evolutionary theory first arose, before Darwin, the assumption was
that this was a process whereby the known simpler forms evolved into
the known complex forms. Evolution could be illustrated simply by taking
the horizontal classificatory scheme and rotating it 90 degrees to form the
evolutionary ladder. Unfortunately, this remains a most influential model.
Dawkinsian evolutionists see no problem with this, for they believe
evolution to be infinitely capable, organisms infinitely plastic. They will
happily force any similar forms into evolutionary series.
The alternative view I have requires a downgrading of the evidence,
a recognition of the pathetically fragmentary nature of the crumbs of
fossils we have, particularly from the Paleozoic. Consider the obstacles
to my view: empiricists will claim that I'm ignoring the evidence, and
producing none of my own, only speculations. Paleontologists must make
their stock in trade appear in the best light, as *the* record of evolution.
Systematists speak of 'parsimony', as they set up phylogenetic charts
that are impressively free of question marks and dotted lines.
The up side of my view is that the world of the past is terrifically richer
than we have been led to believe. Give it a try.
--Cliff Lundberg ~ San Francisco ~ cliff@noe.com