Interestingly, white skin has been found to be a genetic mutation (in fish of all things):
Scientists said yesterday that they have discovered a tiny genetic mutation that largely explains the first appearance of white skin in humans tens of thousands of years ago, a finding that helps solve one of biology’s most enduring mysteries and illuminates one of humanity’s greatest sources of strife.
Wow, what a surprise eh? Yes, that’s sarcasm. Given that everything about us is a mutation, skin color is just another thing among many that now has proof of it.
The Washington Post article has a good point though – the white skin appeared in one human being as the exodus out of Africa was occurring. At that time, Europe was in the grip of an Ice Age, so white skin would have been beneficial in a whiter environment. Being able to blend in easier in the environment, especially when hunting, would be a useful “mutation” to have.
The work by Penn State University also reveals that Asians’ relatively light skin color is the result of different genetic mutations, which means that skin color mutations have risen twice in human history.