system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do white people have so many different hair colors (blonde, red, brown, black) while all other races all have black hair?
gpt
Because the genes that cause dark skin and dark hair easily override toe genes that don't produce as much melanin.

White people, practically by definition, don't produce as much melanin, therefore allowing hair color traits that require less melanin to be visible to show up.