Re: Body Hair Loss in Aquatic Mammals
H. M. Hubey (hubey@pegasus.montclair.edu)
19 Oct 1995 17:03:22 -0400
bbur@wpo.nerc.ac.uk (Bill Burnett) writes:
>Actually, believe it or not, merely pumping blood at 37'C into the
>brain is not going to raise the brain temperature and cause 'heat to build
>up'.
You must think everyone is a fool or misread on purpose. Brain
also has cells that participate in metabolic processes. It's
probably one area of the body which is densest in such
"constantly working cells" and might be one area which generates
heat most of the whole body. I can't recall experiments on
this but I think various types such as sugar consumption for
various tasks have been done. There might also have been
experimetns conducted for studying vs relaxing students and
maybe even infrared photos taken of humans extcreting heat.
And if heat DOES build up in the head, then any increased blood
>flow should conduct it AWAY (if 'conduct' is the right word.). Even _my_
>physics is up to that.
Yes, unless the sun is beating down mercilessly on top of the
head and raising the surface temperature even higher than
the inside temperature. Your physics should be up to that too.
>*WARNING, ANECDOTAL EVIDENCE*
>In fact, hair on the head is adaptive for cooling.
No kidding. That's what everyone is saying. Why lose hair everywhere
except the head ? Maybe only the head was exposed to the sun
instead of the whole body? Where would this happen? Did they
bury themselves up to their necks in the dirt in the savannah?
--
Regards, Mark
http://www.smns.montclair.edu/~hubey
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