Dear Sue,It IS true that being out in the sun Too long Can produce sunburn -- have experienced that myself a time or two. But that Does heal and the person's skin returns to it's 'normal' color. And besides the sunburn is the skin turning pink / burning. And with some people their skin doesn't turn pink and burn -- it turns Tan. Some people who are out in the sun a Lot do have beautiful Tan skin.
Traveling long distances on foot Isn't going to change the pigment of a person's skin.
But inter-marrying -- people of various skin colors marrying other people of Other skin colors Will affect the skin color of their children. That's plain genetics.
And all of this Did start with the people being dispursed into various language groups and thus -- over time -- various colorations , etc, did develop.
I feel you are trying to apply logic of a lifetime not logic over a period.
What I am trying to explain is, when God scattered the people across the world after mixing their talking, babbling, language at Babel, they were scattered in the colour they were at that time, most likely middle eastern complexion and colour.
After arriving where ever they did, some Russia, some China, some India, some Europe, some South Africa, some Norway and the north. At first they were the colour they were scattered, but 'over time', generation after generation, there bodies became accustomed to the weather, the sun, the sun light, in the warm areas more so, in the hottest areas more extreme, in the cool areas less sun light, in the icy areas even less, so 'over time', generation after generation, their bodies changed colour. After all they didn't travel much, travel has only really increased in the last 50-100 years. I was not saying the people at that time got more sun so got sun burnt.
We appreciate intermarriage of colours in our day and age change the colour of siblings, we were looking at the time from Babel for the 1000's of years after they had been scattered all over the world.
Hopefully I have explained this a little better what I was trying to say.
At the end of the day, we don't know, God who scattered then and mixed their language could have changed their skin colour, what we do know is scripture only mentions their language and scattering, it doesn't mention skin colour.