Re: Morgan; various
Thomas Clarke (clarke@acme.ist.ucf.edu)
6 Nov 1995 13:14:07 GMT
In article <815607511snz@crowleyp.demon.co.uk> Paul Crowley
<Paul@crowleyp.demon.co.uk> writes:
> In article <47d7p0$47t@news.cc.ucf.edu>
> clarke@acme.ist.ucf.edu "Thomas Clarke" writes:
> > I favor the fat layer being a response to hairlessness in the night
> > air. <snips>
> > My experience with cold is that if you keep the core body well
> > insulated (body fat, proximal limb fat will do nicely) that the
> > distal limbs can get quite cold. I have walked miles in subfreezing
> > weather wearing thin "Florida" pants, but a borrowed "Northern" parka.
> > My legs got cold and and even a little numb, but still functioned.
> > So actually the fat layer is about what I would expect for protection
> > from cold night air in the absence of hair.
> Our ancestors must have had a significant death rate from exposure.
> Surely the most obvious selective response to this during the last
> N Myr would have been to put on a bit of fur? Most European males
> have hairy legs (and many females). It would have been so easy to
> make that hair a bit thicker - and to get some hair back on the
> trunk. The goose-pimple response is still there. My hairy chest
> and back keep me noticeably warmer than most.
Well actually, the simplest selective response would have been not
to loose the hair in the first place (I'm assuming a hairy CA),
just at the easiest response to locomotion would have been to
remain quadrapedal.
The hairy biped would have had to cope with the noon day sun,
however, and it appears to be supported by calculationa and
experiment that hairlessness and sweat is a viable solution to
the insolation problem.
> Fat is wrong solution altogether - a) surplus food is needed;
> b) it increases weight, reducing speed and endurance.
Fat is the wrong solution, but then so is bipedalism.
Humans are just the wrong sort of animals :-)
> You don't see athletes or wild animals with much fat for a
> lot of very good reasons.
You are extrapolating from current conditions to the past.
Somethings I think that Lucy might have been a nice rolly-polly
sort of gal.
Nor should you compare wild animals, that is the main question of
this thread currently. Is the human skin fat layer significantly
different from apes and other animals so as to require an explanation?
> You've not been up to your usual standard recently, Tom. Been
> under the weather or something?
Thanks for the off-hand compliment. I have been busy.
Also, I've been toying with alternative theories for the
differences between humans and apes, they are still a bit
ill-formed.
Tom Clarke
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