Re: Article: On the Origins of Chemical Biodefense

lamoran@xxxxxxxxxxxxxxxxxxxxxxx (Larry Moran) wrote in
news:dj35oq$29mf$1@xxxxxxxxxxxxxxxxxxx:

> On Tue, 18 Oct 2005 00:56:20 -0400 (EDT),
> William Morse <wdmorse@xxxxxxxxxxxx> wrote:
>> lamoran@xxxxxxxxxxxxxxxxxxxxxxx (Larry Moran) wrote in
>> news:diu8pu$7bb$1 @darwin.ediacara.org:
>
> [snip]
>
>>> There is a controversy in the field of molecular evolution. Some
>>> people, like me, believe that convergence explains many common
>>> sequence motifs. We believe it's very unlikely that all traces
>>> of sequence similarity could be lost in regions that must preserve
>>> structural integrity while randomly changing all the amino acids
>>> in order to wipe out sequence similarity. That just doesn't make
>>> a lot of sense.
>>
>> It's very strange to hear Larry arguing for convergence - this is the
>> adaptationist stance.
>
> The adaptationist program tries to account for everything by invoking
> natural selection. When you call someone an adaptationist you mean to
> imply that they are going too far and they are ignoring other
> possibilities.
>
> Pluralists, as the name implies, do not deny that natural selection is
> a common and important mechanism of evolution. It should not surprise
> you to discover that a pluralist can invoke selection. That's what we
> do.
>
>> Convergence on a common protein structure from diverse lineages over
>> millions of years? Surely that cannot be due to neutral evolution -
>> the odds against are astronomical.
>
> Pluralists do not argue that everything has to evolve by random
> genetic drift. That would be a very silly position to take. Did you
> really think that's what I proposed, or is this sarcasm?

Sorry, Larry, I should have put a few smiley faces in that reply - I
just couldn't resist responding when I saw you invoking convergence. And
I think you know that while my knee-jerk reaction is adaptationism, you
and others have managed to educate me enough to recognize the importance
of the various neutral mechanisms in evolution.

But Larry, if I don't argue with you I'm going to be stuck like PIP
responding mostly to those who aren't interested in learning anything
new, and then I would have to keep my big mouth shut most of the time.
We can't have that :-)

BTW, I think you'll note that after getting in a few digs re:
adapationism my follow actually agreed with your position on the
original topic.

Yours,

Bill Morse

.

Relevant Pages

  • Re: Convergence leaves the evolutionist completely dumbfounded
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    (talk.origins)
  • Re: Species diversity through time
    ... you think that the history of life is indeed a series of inevitable ... The sample size for some cases of convergence is in the ... islands is a fair approximation of this "runnin the tape again" thing. ... evolution in a more modern way. ...
    (talk.origins)
  • Re: Convergence leaves the evolutionist completely dumbfounded
    ... > biological convergence, an analysis of this feature of nature can be used to ... > facets of biological convergence. ... since these three birds are unrelated to ... so convergent evolution, by some mechanism or other, is logically required. ...
    (talk.origins)
  • Re: Convergence leaves the evolutionist completely dumbfounded
    ... > biological convergence, an analysis of this feature of nature can be used to ... > facets of biological convergence. ... think that convergence would be a problem for evolution. ...
    (talk.origins)
  • Re: evolution v. selection (was: evolution explains what?)
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