Re: Sweating hominids

See: Brain Cooling: An Economy Mode of Temperature Regulation in
Artiodactyls - Claus Jessen
The key to this extraordinary thermoregulatory performance in high
solar radiation appears to lie

-in the insulation provided by the fur.

No quantitative measurements have been made on the pelage of the black
wildebeest, but in hartebeest, a member of the same subfamily and
dwelling under similar conditions, the low absorptivity of the fur for
shortwave radiation and the preferred orientation of the body relative
to the sun reduced the effective radiative load to one-third of the
potential load. In addition, the low thermal conductivity of the thick,
dense pelage led to high surface temperatures, with subsequent
long-wave radiative and convective losses of much of the absorbed heat
..The insulation provided by the pelage does not protect the animals
against hyperthermia resulting from diurnal activity, and, indeed,
wildebeest are known to spend the middle of the day inactive. The
conclusion is that well-hydrated wildebeest withstand, by a combination
of perfect external insulation and appropriate behavior, even extreme
external heat loads without developing significant degrees of
hyperthermia. Similar observations were recently made in springbok, a
smaller antelope living in the same habitat
http://physiologyonline.physiology.org/cgi/content/full/13/6/281


So what makes naked sweating humans any better at dealing with savannah
heat?

And what makes you think mosquitoes are as prevalent in the tropics as
in 'temperate' regions like Canada or Scotland ? I've lived in all
three, and I can tell you where I feel more comfortable in a windless
early evening.

Malaria is a bit different, but then, it requires a human vector to
spread - not much chance of it doing very well where other humans are
scarce or absent.

regards

Richard

.

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