Re: fat
Thomas Clarke (clarke@acme.ucf.edu)
2 Nov 1995 03:11:04 GMT
In article <47935n$brb@geraldo.cc.utexas.edu> Alex Duncan <aduncan@mail.utexas.edu> writes:
>In article <477v5p$qs@longwood.cs.ucf.edu> Tom Clarke,
>clarke@longwood.cs.ucf.edu writes:
>>Every seems to be ignoring my chill fluid suggestion. But then
>>I haven't written a book that everyone loves to hate:-) I still
>>think there is enough correlation between the size and extent of
>>the deposits and exposure to chilling fluid in the absence of hair
>>or fur, that a period of such exposure can be inferred for hominids.
>
>There are several problems with this. We've already noted that all
>primates (probably all mammals) have subcutaneous fat, and that humans
>are not unique for this feature. The apparent human uniqueness is the
>large quantities we develop, but this feature looses its uniqueness when
>we examine domesticated or captive animals.
I don't like the flavor of this counter argument. It's a little
like saying all mammals have brains so that humans are not unique
in this feature.
I will have to be more observant of this feature, though.
I've been trying to remember if I have seen a cross section of
a cow to compare its fat with the cross section of a pig, which
I have seen.
>The second major problem is the distribution of fat over the human body.
>It tends to be concentrated over regions (abdomen in males, upper thighs
>& buttocks in females) that are not the most subject to rapid heat loss.
>Because of their shapes, the distal limb elements are the most subject to
>rapid heat loss in an aquatic environment, and these are the parts of the
>body where we see the LEAST subcutaneous fat. In fact, skin over the
>forearms and shins (dorsal surfaces of feet and hands too) is paper thin.
No pinch your arm. There is a thin upper layer that is the dermis
and a thicker underlayer that is the fat. These layers are only
distinguishable by a change in texture, they do not slide over each
other. The two layers together, however, do slide over the lower
tissues. It is this fat layer which is under discussion, not the
fat deposits you get when you put on weight. [At least that is how
my arm feels and while I am tending to lovehandles and such, my
arms are fairly muscular from woodworking]
The skin on the backs of my hands seems to lack these deposits, but
then hands are kind of passive articles - remotedly operated by
tendons like "chicken feet".
As I pointed out elsewhere by pushing nakedness back,
and ascribing the fat layer to nakedness in air, you reduce the
power of the fat argument for an aquatic episode.
And you guys have convinced me, nakedness and bipedalism go
together because of the thermal advantages.
Tom Clarke
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