Re: Junk DNA: A hypothesis

From: Tim Tyler (tim_at_tt1lock.org)
Date: 01/27/05 

Date: Wed, 26 Jan 2005 23:50:38 -0500 (EST)

Perplexed in Peoria <jimmenegay@sbcglobal.net> wrote or quoted:
> "Tim Tyler" <tim@tt1lock.org> wrote in message news:ct61nj$1uvo$1@darwin.ediacara.org...

[regarding PRQ]

> > So what? Their reward is healthy offspring and long-term
> > ancestry. Why should they care if they die if their genes
> > survive? Benefit to an organism is measures in terms of
> > the number of their long term descendants - not whether
> > they are alive or not.
>
> Since my first response, I have thought of a better, more direct,
> response. I am going to claim that healthy offspring is not
> a "reward". An organism is not interested in having healthy
> offspring, per se. What it is interested in is having offspring
> that are healthier than the offspring of other members of the
> species. But PRQ does not provide this reward. It increases
> the health of everyone equally (or rather, gives everyone the
> same increased chance of good health. To an organism in competition
> with everyone else, there is no particular benefit in having the
> playing field improved, as long as the playing field remains level.

We are probably at cross-purposes here...

Red queen theories don't seem to involve equal benefit to everyone to me.

The classic example would be mutations that cause parthenogenesis.

The disadvantage relating to parasite resistance there is not distributed
to all members of the population equally - it concentrated in the
offspring of the individual with the mutation.

That's an extreme example - but I expect the same would apply to other
mutations that reduce evolvability - immediate offspring of the mutated
individual are most likely to be affected - since they are the ones
most likely to have the mutation. 

-- 
__________
 |im |yler  http://timtyler.org/  tim@tt1lock.org  Remove lock to reply.

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