Dark skin evolved 1.2 million years ago in early hominids. Dark skin evolved to protect against UV radiation and folate depletion. All modern humans were dark-skinned by the time Homo sapiens evolved
Human skin color ranges from dark brown to lightest hues. Skin color depends on genetics, sun exposure, and melanin production. Melanocytes produce two types of melanin: eumelanin (dark) and pheomelanin (light)
Brown eyes are most common worldwide, affecting over half of the population. Eye color is determined by pigmentation in the iris, which contains melanin, pheomelanin, and eumelanin. Brown eyes have melanin in both iris layers, while lighter eyes have melanin only in the back layer
Melanin is a pigment produced by melanocytes in the skin. It determines skin, hair, and eye color. Melanin protects DNA from UV radiation. Melanocytes produce two types: eumelanin (brown/black) and pheomelanin (red/yellow)
Melanin determines skin, hair, and eye pigmentation. Melanocytes produce melanin in hair, skin, eyes, and brain. Three main types: eumelanin, neuromelanin, and pheomelanin
Eye color is determined by more than 50 genes, not just one. Eye color is controlled by melanin pigment in the iris stroma. Three main pigments: melanin, pheomelanin, and eumelanin. Brown eyes are dominant, blue eyes are recessive