why africans have curly hair
Answers
Of course it has to do with evolution. That is the way they evolved in Africa with black curly hair and a dark complexion. The dark skin protects against the sun and that the hair is curly helps to protect their head. Whether curly hair is better or not, that is the way they evolved.
You should ask why people have straight hair and why they are white when they need protection against the sun. It is because of a recessive albinism gene. It causes white skin, blue eyes and straight hair.
People like to believe because it was because of vitamin D. If you don't get your vitamins, you die. Your body doesn't just make it. A lot of white people were getting rickets in the last century, so they had to add vitamin D to milk and cereal. This turning white didn't do a very good job. Shouldn’t all animals living in the cold north be white so they could metabolize vitamin D? They aren't, they are all colours.