Subject: Are fair skin or fat deposits good indicators of ancestral lineage in very cold regions?

Is skin tone an accurate indicator of where your direct ancestors evolved? In 
particular is it safe to assume that a fair skin means that your pre-
agricultural revolution ancestors evolved in a far northern latitude with low 
levels of sunlight quantity and intensity? 

Also, were paleolithic humans in cold areas selected for ability to get fat?
Whilst I am aware of the discussion about the "fat gene",can you confirm that 
in colder climates ( equal chicago today ) only humans able to quickly gain 
weight in a short annual ( fall ) period of plenty could have survived the 
severe winter/early spring?  

Re: Are fair skin or fat deposits good indicators of ancestral lineage in very cold regions?