From: Ray Recchia (rrecchia@mail.clarityconnect.com)
Date: Tue 06 May 2003 - 01:14:48 GMT
Thanks for the effort Chris. Don't sweat it too much. I may try to look
Wilson after I finish his book and I'll see if he has any examples
Jake, I think the term "atavism" is fairly close to what I'm looking for,
but it doesn't seem quite the same. Atavism would seem to cover the stage
where the spotting mechanism disappears with point mutations but not the
potentially quicker re-evolution of the spots again when the environmental
condition for their selection re-appears.
The book 'Darwin's Cathedral' by the way has more to do with cultural
selection of religions. The idea for latent adaptation came when he was
discussing guppy species differences in response to different types of
predation. Because the differences in predation seem to me to be things
that might fluctuate within the environment on a fairly frequent basis I
thought something like a 'latent adaptation' might end up present within
the species.
At 05:48 PM 5/5/2003 -0700, you wrote:
>aren't point mutations those undesirable things that "bad" dna have? heh. I
>don't think that species would evolve to include point mutations since this
>would mean screwing up all of their dna. think more. if a species is both
>gray and spotted, when gray is good and spots are bad (since it wouldn't
>un-evolve the spots hm?) won't it like, get killed? that's not good. read
>selfish gene, by dawkins. best dna book out there.
>
>always, sabrina
I don't think you got it. I'll spell it out a bit more clearly
Under environmental condition 1 a bland grey animal is better camouflaged.
Environmental condition 2 arrives. Grey bland animals are no longer the
best camouflage
Over time our species slowly evolves the ability to appear with
spots. Under environmental condition 2 spotted animals are better camouflaged.
Environmental condition 1 returns. Now spots are no longer the best
camouflage again.
Instead of completely eliminating all the genes for spots, they are just
disabled with point mutations that prevent the genes from expressing
themselves and the species returns to its grey state.
Environmental condition 2 returns. Now spotting can reappear much more
quickly because instead of having to re-evolve the entire spotting
mechanism only the disabling point mutations have to be reversed.
I don't think this is something Dawkins discusses, although I see nothing
in his ideas that would contradict the possibility of it happening. I did
read 'The Selfish Gene' and I agree that it is quite a good book.
Ray Recchia
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