Where do differences in skin color originate from?
In: Biology
It seems to be a balance of vitamin D production vs. preventing skin cancer.
Dark pigmentation protects from UV, but UV is used in your skin to make vitamin D.
People in Northern latitudes tend to be lighter so they can still make enough vitamin D even in the less sunny winter months, and there’s less danger of skin cancer as well.
People along the equator are darker because they get more even, strong sun, and so they can make enough vitamin D even while blocking most UV and protecting themselves from cancer.
Also, making pigments takes some effort, so if you can get away without spending resources on them, it can be beneficial. This is why many cave-dwelling creatures lose pigmentation. If there’s no one to see you and no sun to block, you’re better off saving those pigment chemicals for other uses.
Latest Answers