On Dec 27, 2007 5:37 PM, Charlie Bell <[EMAIL PROTECTED]> wrote:

>
>
> 4) Over enough generations, different selection pressures applied to
> different parts of a population (or even just drift, if the geographic
> range is significantly larger than the geographic range of family
> groups), causes enough accumulated change to prevent those populations
> from breeding if they cross paths, at which time they are said to have
> speciated.


Except... that a species often isn't clearly delineated.  IIRC, there are
many species, oops, kinds of seagulls that can interbreed with those who
live nearby, but they can't interbreed with the ones that are further away.

And there are animals that are pretty much unable to breed for physical
reasons -- dogs whose physiologies are so different that it just doesn't
work.

I don't mean this just to be picky.  I'm not sure what significance to give
the second point, but the first one is pretty hard to deal with from a
creationist standpoint.  I don't recall anything that says God created a
continuum of similar creatures.  But creationists consistently
under-estimate God's abilities.

I hope nobody here has imagined that I disagree for a moment with the
historical reality of evolution.  My only doubts, which aren't really even
doubts, but a belief that there are significant discoveries yet to be made,
are about the mechanisms at work.

>
> incorporated into the neo-Darwinian synthesis of Mayr,
>

Ernst Mayr!  I've been trying to remember his name.  When I was in high
school, learning genetics (on my own -- it fascinated me), Mayr spoke at the
college where my dad taught.  I got to meet him.  I remember that he had the
audience try to roll their tongues and explaining that it was an inherited
ability.

Here's a quote I just found from him, via Wikipedia:

"*The idea that a few people have about the gene being the target of
selection is completely impractical; a gene is never visible to natural
selection, and in the genotype, it is always in the context with other
genes, and the interaction with those other genes make a particular gene
either more favorable or less favorable. In fact,
Dobzhanksy<http://en.wikipedia.org/wiki/Dobzhansky>,
for instance, worked quite a bit on so-called lethal chromosomes which are
highly successful in one combination, and lethal in another. Therefore
people like Dawkins in England who still think the gene is the target of
selection are evidently wrong. In the 30's and 40's, it was widely accepted
that genes were the target of selection, because that was the only way they
could be made accessible to mathematics, but now we know that it is really
the whole genotype of the individual, not the gene. Except for that slight
revision, the basic Darwinian theory hasn't changed in the last 50 years*."

Ahhh... Now I'm thinking Mayr influenced me quite a bit so many years ago.
Those words do a great job of saying where I think Dawkins and his ilk go
wrong.

Nick

-- 
Nick Arnett
[EMAIL PROTECTED]
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