>Terry, wouldn't it seem equally as plausible that a designer God would create
>beings with the genetic capability to adapt to what you call "stressful"
>circumstances, and rapidly at that? These rapid micro-mutations work
>beautifully. But the evidence doesn't suggest major change occurs this way.
>
>What about that scenario? Why must one take a leap to major change based upon
>beaks?
>
Don't read too much into what I wrote. My chief reason for accepting
macroevolution is NOT observed instances of natural selection in Galapagos
finches or elsewhere. I don't take a leap to major change based upon
beaks. (Although given the other evidence for macroevolution, I don't
think it's much of a leap at all.)
One of these days I'll get this defense written in an essay form (although
in my opinion it's not that different from standard treatments; I guess I
have less reason to reject evolutionary thinking than some of you, so I'm
more open-minded (or more easily duped :-) But here's the gist of it.
1. The progression of the fossil record (without concern for transitional
forms) supports common ancestry (macroevolution).
2. Sequence comparisons (and known mechanisms of how sequences mutate)
support common ancestry (macroevolution).
3. Biogeography supports common ancestry (macroevolution).
4. Systematics support common ancestry (macroevolution).
On the word "support"... No doubt progressive creationism is supported
just as well with the exception of the mechanisms mentioned in #2.
Depending on how far Stephen Jones (and Mike Behe for that matter) are
willing to take it, I would say that their progressive creative acts look
no different empirically than a punctuation and a macromutation and/or a
emergent phenomena (a la complexity theory). There preference for the
special creationist option over the evolutionary creationist option appears
(to me) to be due to what they consider to be the impossibility of such a
transition to occur "naturally". I am not prepared to say that such things
are impossible, especially given developments in developmental biology and
complexity theory. I judge that it is extremely premature wrt our
understand of developmental mechanisms to say that certain things can't
happen. I don't claim to have the explanation as to how they did happen,
although I think that there are several hints that make it more than just
wishful thinking or an uncritical optimism that they can and did happen.
(I alluded to some of these in the paper I gave at the ASA meeting last
summer).
In my opinion (I don't care what Darwin says so don't quote him to me),
mechanism is not that important. It's nice and it would complete the
explanation, but it's not essential to confirm the theory (empirical
evolution, I guess in PEJ's terms) Mutation + natural selection provides
some mechanism. Macromutation and complexity theory promise others. No
doubt there's alot we don't know, but from my point of view, the ball is
rolling in favor of establishing macroevolution rather than causing it to
crumble.
_____________________________________________________________
Terry M. Gray, Ph.D. Department of Chemistry and Biochemistry
Calvin College 3201 Burton SE Grand Rapids, MI 40546
Office: (616) 957-7187 FAX: (616) 957-6501
Email: grayt@calvin.edu http://www.calvin.edu/~grayt