[@Myrna Minkoff]

[hider=Regarding the Fish]
Just out of curiosity do you have a source for the vitamin D making skin darker. 

From what I understand in colder climates when people have darker skin it's usually because they're getting the vitamin D from fish rather than having to produce it in their skin, the process for which would have been inhibited by the presence of melanin. This alternate method of receiving the vitamin allows evolution to select for darker skin as a beneficial trait. 

This is to say that the skin tone in this case is the product of evolution and not epigenetic and as such could not be acquired through a diet rich in fish without many generations of such. 

Take what I just said with a grain of salt though and tell me if I've misunderstood something, I might have. I just thought you might be interested. 
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