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Pauline M Ross wrote:
> On 26 Jun 2005 10:29:53 -0700, "JAE" <jae@xxxxxxxxxxx> wrote:
>
> >>[Pauline] As to when sweat-cooling evolved, I don't know that either, but
> >>two
> >> things are evident: that it didn't happen overnight, and that,
> >> whenever it happened, copious amounts of water were readily availabl> >>
> >> at that time and subsequently.
Well stated.
<snip>
> It just means they had to have a permanent water
> source somewhere on hand.
Yep!
>
> I don't know much about patas monkeys, but whatever water they lose by
> sweating will also need to be replaced, somehow or other. It would be
> interesting to know how they do it.
>
> As to the "copious" amounts sweated, the Cambridge Encyclopedia of
> Human Evolution says: "The efficiency of the human cooling system
> incurs one significant liability: the need for a large intake of
> water. A man weighing 90 kilograms can sweat over 2 litres of water in
> an hour of normal walking on a hot day in the desert. [...] Throughout
> evolution, human populations in hot savannas must have stayed
> relatively close to water until they were able to domesticate animals
> to carry their water supply..."
>
> I'm not sure animals are needed to carry water, and I'm not sure that
> 2 litres an hour applies universally (I presume humans in water-scarce
> areas adapt somewhat to that by losing less), but the principle
> remains - a "large intake" is needed, and whenever sweat-cooling
> evolved there must have been a reliable supply of water available.
You still don't get 'it,' you idiot. It means early hominids *must*
have been communal. (This fact, in and of itself, turns currents
assumptions on their head.)
Jim
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