Posted: Apr 10, 2018 1:11 pm
The_Piper wrote:Skin cancer would have to regularly be contracted in the first 20 years of life for it to be the major driving force for dark skin, would be my guess.
Perhaps that's not actually a requirement for it to be a selective force. I believe humans are perhaps the only species where individuals live well past their fertility age, possibly because grandmothers/fathers helping to take care of their grandchildren offers an advantage. So if you lose your parents due to them contracting skin cancer at an older age, you and your ofspring are at a disadvantage so even in this case it would still be an evolutionary selective force.