About 2 years ago, at the Albertson's grocery across the street, a grocery bagger forgot to take his meds and came to work in a trenchcoat, with a sword. Highlander style. He proceded to decapitate a few people until being shot with a rifle down the aisles. When his picture was published, I recognized him, my kid & I have had him bag our groceries. Far out.

I think Albertson's was intentionally hiring mentally ill. Once, there was a young woman who was entirely tattooed, including her (blue) face. She had to wear gloves, no doubt her hands were covered too. When I was in line with the kid, age maybe 4-5, he asked in no whisper why she was painted like that. Decoration, I said, and that worked.

Once we were at Fry's and the kid asked why a guy in the aisle was black. I said, to protect him from the sun, but of course, that oversimplified too much; he was black because his parents were, and they were because their parents were, etc. The reason for that was because their ancestors were in an environment where melanin was sufficiently useful as to be worth the cost of protein synthesis, and some ancestors had come up with those genes. Ie, albinos (and relative albinos like European self) didn't have as many kids.

Of course, when some groups went to less sunny places, it was adventageous to lose the melanin, because you need to get some sunlight eg for vitamin D. There is no absolute "useful" in evolution, its a function of environment.
The first lizard with scales that lifted off looked like a freak to his peers, but he survived the cold better, or survived jumping off a treelimb by gliding better.

Richard Dawkins is God.