Dean Esmay (I believe) raised this point in a previous message:

>One might also wonder about dairy.  I know of no evidence that the
>ancestral human diet would ever include dairy.  In fact, although I
>eat dairy products myself, you could argue that the consumption of
>dairy is just about the most bizarre thing that modern humans do.
>Dairy products contain lactose, and compellingly, about 75% of the
>world population is lactose-intolerant.  But lactose isn't the only
>foreign substance; casein is also in all dairy products, and is
>another substance which would be foreign to the human digestive tract,
>and which appears to cause at least some individuals problems.  I know
>of no rigorous evidence that casien is a major danger, but it does
>seem logical to posit that substances unique to foods that would never
>have been eaten by humans  in nature should be looked at with
>suspicion.

With Susan Cheer, I have recently published a paper in Current
Anthropology called "The non-thrifty genotype" (37:831-842, 1996), in
which I provide a somewhat heterodox view of the Thrifty Genotype
concept and attempt to link lactose tolerance and use of dairy
products to the issue of why European-derived populations appear to
be virtually unique in not possessing the Thrifty Genotype.  Lactose
is a simple sugar, and those were (are) unusual in hunter-gather
diets.  In addition, the proteins in milk are evidently insulin
secretogogues, thus the insulin response to lactose in milk is much
greater than to lactose alone (ie, mixed in a solution of water).
Anyway, I have tried to make a consistent evolutionary story about
these facts and a few others.  The most fundamental observation
raised in the paper is that populations with high lactose tolerance
rates have low rates of Type II diabetes; the relationship is quite a
strong one despite all the other factors that one would think would
be involved.

If anyone would like a copy of the article, just send me an e-mail.

Cheers, John Allen

**********************************************************
Dr John S Allen
Department of Anthropology
University of Auckland
Private Bag 92019
Auckland, NEW ZEALAND
64-9-373-7599, Ext 8574 (office)
64-9-373-7441 (fax)