Re: milk and human sociobiology

John A. Halloran (
21 Jan 1997 21:00:14 -0700

In article <5c419b$> Mennen) writes:

>In <5c3c97$> (Gerold Firl)
>>I am interested in the evolution of dairying, both as a cultural
>>process and a biological one. In fact, this is a perfect example of a
>>process which can *only* occur as a synchronous socio/biological
>>evolution, where people learn how to use their domesticates as dairy
>>animals and integrate new customs into the culture, while at the same
>>time spreading the genes for adult lactose tolerance throughout the
>>population. I'm wondering how well that process is understood; I
>>haven't seen much comment in the literature.
>>Based on the limited extant of lactose tolerance among human
>>populations (concentrated among speakers of IE, semitic, and
>>nilo-saharan languages) it appears that lactose toleration became
>>an adaptive trait fairly recently. Campbell cites tentative dates of
>>3500-4000 bc for polychrome mosaics of the milking, straining, and
>>storing of milk at the temple complex of Obeid in iraq; this is the
>>earliest evidence of dairying that I am aware of. Has the dating been
>>refined? And does evidence of earlier dairying exist?

Who is Campbell? What is your reference, please?

>>Here is an interesting question: did the genes for lactose tolerance
>>diffuse outward from a single source, or did evolution locally select
>>for it in areas where cattle were kept for meat? Actually, both
>>processes undoubtedly occured, but which was faster?

Another related question is the differences or similarities between the milk
of cows, goats, and sheep. The cow was the principal milk animal, but people
who have an allergic reaction to bovine protein can usually tolerate goat
milk (this is a different issue from lactose intolerance). Goats and sheep
were domesticated somewhat earlier than were cattle.

>Does lactose intolerance (LI) really lead to differnetial reproductive
>rates and ultimately, success or failure? Persons with LI can deal with
>milk products but get gassy and crampy, etc. It is not fatal.

It could be if individuals drank differential amounts due to these symptoms
and thus benefitted differentially. And do the systems of individuals with
lactose intolerance really utilize milk as efficiently?


John Halloran