[net.misc] Truth in Advertising?

donn@utah-gr.UUCP (Donn Seeley) (11/26/84)

(None of this discussion has really been a good topic for net.cooks --
let's move it to net.misc or net.flame.  Actually, net.flame has a nice
ring to it when discussing properties of heat absorption and
radiation...)

From faustus@ucbcad.UUCP:

	What I've always wondered is why the closer to the equator
	people live, the darker their skin tends to be. It seems that
	in the interests of maintainting a reasonable body temperature,
	it should be just the opposite.

		Wayne

Actually it's the skin shading of Caucasians that's more interesting.
(My apologies to speakers of Kartvelian languages -- 'Caucasians' here
refers to pale Europeans in general.)  The skins of Caucasians darken
upon exposure to sunlight, but this seems to mean that more radiation
is absorbed, not less.  This is often referred to as 'tanning',
although for me 'tanning' your skin means peeling it off, immersing it
in smelly and corrosive liquids, then nailing it to a wall.  Isn't this
darkening exactly the wrong way to go about maintaining body
temperature?

The 'body temperature' question is a 'red herring'; dark skin absorbs
radiation in order to prevent it from penetrating into layers beneath
the epidermis and causing damage (sunburn).  'White' skin is really
transparent skin.  People in sunnier climes are in more danger from
radiation, so they tend to have darker skin.  Of course skin shading
also has a lot to do with where your ancestors came from, since
populations don't change skin shade overnight...  (Unless they're
Caucasian chameleons!)

It's always been amazing to me that the body's defense against
radiation can be used to rationalize seating arrangements on a bus,
or even more foolish things.

Donn Seeley    University of Utah CS Dept    donn@utah-cs.arpa
40 46' 6"N 111 50' 34"W    (801) 581-5668    decvax!utah-cs!donn

crm@duke.UUCP (Charlie Martin) (11/28/84)

I haven't made an extensive survey on this, but I remember the
first time a black friend of mine came back from the ocean
after vacation with a) a sunburn and b) tan lines and wonder if
there is all that much difference other than starting state...
-- 
		What is the sound of one hand, clapping?
		Toop, toop, toop.


				Charlie Martin
				(...mcnc!duke!crm)

eac@druor.UUCP (CveticEA) (11/30/84)

I thing its high time we move this discussion out of net.cooks.

Thank you.

Betsy Cvetic

john@dicomed.UUCP (John S. Salmi) (12/03/84)

In article <> eac@druor.UUCP (CveticEA) writes:
>I thing its high time we move this discussion out of net.cooks.
>
>Thank you.
>
>Betsy Cvetic

It's about time someone brings this up!
-- 

  John Salmi - "the software guy"                             
  DICOMED Corporation                                         
  Minneapolis 

  {ihnp4,mgnetp,uwvax}!dicomed!jss