--- In FairfieldLife@yahoogroups.com, "shempmcgurk" <shempmcg...@...> wrote: <snip> > I'm not a biologist or geneticist but I think that > 10,000 years is more than enough time for a species > to select genetic traits. So I think you strengthen > my point by reminding us that it's "only" been > 10,000 years that dairy has been a part of the human > diet.
In fact, in populations that continued to drink milk beyond weaning age, there *has* been genetic adaptation, at least with regard to lactose intolerance. But dairy has not been part of the human diet universally by any means since 10,000 years ago, so the gene that turns off the ability to digest lactose after weaning persists, in widely varying percentages among groups with common ancestry (Ashkenazi Jews and others of Northern European ancestry, for example, have a very low percentage of lactose intolerance, whereas African Americans have a very high percentage).
