Re: Is it possible for a person to change his skin color in N pole

Basically, I would have to say yes.  I'm not certain if 1000 years is enough 
time, but I think there would be a change in skin color.

Typically, people with a lot of melanin in their skin, such as those of 
African descent, are well adapted to living in areas where the amount of 
sunlight is high enough to damage the skin cells.  The melanin forms a 
shield around the delicate cellular structures, particularly the 
chromosomes, and prevents them from being damaged by the ultraviolet 
radiation.  In a way, it is a natural sunblock.

Anthropologists think that as peopled moved further north, especially into 
Europe, that the need for all that melanin was not as great.  A lot of 
energy is used by a body to produce all the that melanin.  If it is not 
needed, then those individuals' genes did not code for melanin would tend to 
live longer and healthier lives and probably have more offspring.  After 
many generations, it is possible to go from a dark race to a light race.  
Also, there may have been another drive to 'whiteness': nutrition.  Another 
idea is that in Northern Europe, there may have been problems with vitamin 
deficiency.  But, some vitamins can be synthesized by the body if it is in 
contact with sunlight.  All the melanin would have gotten in the way, so 
there may have been a selective advantage to not having melanin.

Of course, an argument against darker people evolving into lighter people 
could be sexual selection.  If our group of dark skinned people did not find 
light skinned people attractive, then we may never get lighter skinned 
people.  It wouldn't matter who is better adapted to survive in the 
environment because the lighter skinned people would have a harder time 
finding mates and producing more offspring.  Sexual selection can often put 
a kink into natural selection.