Dick Bird wrote:

>Second, the envelope of the body grows in area with more mass (albeit
>proportional to the sqare root of the mass ) and so more heat is lost
>to the environment.

Dick may want to rethink his physics.  Fat people should have less surface
area for every kilogram of body mass than thin people.  The amount of fat
will grow much faster than the skin needed to contain it.  In this sense
extra fat would provide a warming effect.

That said I have never seen any meaningful correlation between body fat and
warm or cold climates.
  -=-

 The mind is not a vessel to be filled.  It's fire to be lit. - Plutarch