Angela Koine Flynn: The science of skin color

The science of skin color

When ultraviolet sunlight hits our skin, it affects each of us differently. Depending on skin color, it'll take only minutes of exposure to turn one person beetroot-pink, while another requires hours to experience the slightest change. What's to account for that difference, and how did our skin come to take on so many different hues to begin with? Angela Koine Flynn describes the science of skin color.

Human skin color is the result of generations of adaptation to sunlight, shaped by the interplay of melanin and ultraviolet exposure. People living near the equator developed dark, eumelanin-rich skin to protect against intense UV rays and deadly melanoma, while those who migrated north evolved lighter skin to absorb more UV and produce vital vitamin D. A person's skin may turn beetroot-pink in minutes or barely change after hours, all due to this biological heritage. Skin color, striking in its variety, tells a story of survival and adaptation—not character or worth.