Wikipedia says:
Dark skin is a type of human skin color that is rich in melanin pigments.
and
In the human skin, melanogenesis is initiated by exposure to UV radiation, causing the skin to darken.
Wikipedia says:
Dark skin is a type of human skin color that is rich in melanin pigments.
and
In the human skin, melanogenesis is initiated by exposure to UV radiation, causing the skin to darken.
But people exist only on Earth so what do you suggest? Earth being some spinning bouncy ball instead of a majestic plane?