On Mon, 18 Sep 2000, Ben Balzer wrote:

> The main point is that EVOLUTION occurs AS A RESULT of selective stressors
> that ACT PRIOR TO PARENTHOOD.

Mainly, but not exclusively.  Difficulties that appear after
parenthood still matter, in evolutionary terms.

> Most of the chronic diseases that paleo protects us from occur BEFORE
> parenthood and thus have NO evolutionary effect.

I assume you meant to write AFTER instead of BEFORE.  If so, then
it would be better to say that they have less effect, rather than
no effect.

> Evolution will only occur in a particular direction if it is actually
> possible for the animal's biochemistry to do that particular thing. If it in
> the too hard basket, it will be a long or non-existent process.

Furthermore, the process is driven by random mutation, and there
is no guarantee that the right mutations will occur.

> I am also saying that the 10,000 years of Neolithic foods would have been
> long enough to make more adaptations if the diet were more toxic and
> affected us more. Most of the adaptations that occur are fairly simple- eg
> persistence of the lactase enzyme in some races, weeding out the odd gene
> that needs too much folic acid etc etc etc. Adapting to lectins take a whole
> lot more mutations than that, and just hasn't happened.

This is connected with something that is a problem for
evolutionary theory in general.  Most mutations are destructive,
involving loss of information.  The loss of the gene for making
vitamin C in the higher primates is a good example.  Getting to a
*new* enzyme by random mutations is a much trickier thing.

Todd Moody
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