On Wed, 1 Apr 1998, Todd Moody wrote:

>I can't see any reason to suppose that populations of humans
>could not become significantly differentiated dietetically in
>40,000 years.

Absolutely!  I know someone who has discussed this issue with a few
nutritional anthropologists.  According to these experts, only 5000 years is
required for significant (but not necessarily complete) adaptation to occur.
It has been estimated that 1,150 years is enough time for lactose tolerance
to become prevalent within a population (see Part 2 of the interview with
Ward Nicholson), and the differences in grain tolerance between populations
arose within a few thousand years.  Diet-based natural selection can be
fierce and fast-acting.  I guess my point is that we should judge which
foods agree with us by trial and error, instead of saying "well, my
ancestors ate fungus-covered rocks 400,000 years ago, so I should too." ;-)

Cheers,
-- Aaron Wieland