Get the world’s most fascinating discoveries delivered straight to your inbox.
You are now subscribed
Your newsletter sign-up was successful
Want to add more newsletters?
Delivered Daily
Daily Newsletter
Sign up for the latest discoveries, groundbreaking research and fascinating breakthroughs that impact you and the wider world direct to your inbox.
Once a week
Life's Little Mysteries
Feed your curiosity with an exclusive mystery every week, solved with science and delivered direct to your inbox before it's seen anywhere else.
Once a week
How It Works
Sign up to our free science & technology newsletter for your weekly fix of fascinating articles, quick quizzes, amazing images, and more
Delivered daily
Space.com Newsletter
Breaking space news, the latest updates on rocket launches, skywatching events and more!
Once a month
Watch This Space
Sign up to our monthly entertainment newsletter to keep up with all our coverage of the latest sci-fi and space movies, tv shows, games and books.
Once a week
Night Sky This Week
Discover this week's must-see night sky events, moon phases, and stunning astrophotos. Sign up for our skywatching newsletter and explore the universe with us!
Join the club
Get full access to premium articles, exclusive features and a growing list of member rewards.
Not to bronze your statuesque physique, although that may be why you tan. Tans are natural shields against the sun's ultraviolet radiation, which can damage skin tissue in the form of a sunburn (as well as cause cancer in the long-run).
Exposure to ultraviolet rays causes certain skin cells to produce the pigment melanin, which darkens through oxidation. Enough beach bumming and those cells will migrate closer to the skin's surface and produce more melanin, further darkening the skin into a suntan. It's no wonder our bodies have developed the ability to produce melanin.
The pigment absorbs ultraviolet radiation and defends against further penetration of skin tissue. In other animals melanin proves diversely useful. It absorbs heat, an essential for cold-blooded organisms. It colors bird feathers, fish scales and squid ink, and helps to conceal nocturnal animals. Melanin even absorbs scattered light inside the eye to sharpen vision.
But it appears that only humans will risk their skins for a little extra surface pigment.
Follow Life's Little Mysteries on Twitter @llmysteries. We're also on Facebook & Google+.
Get the world’s most fascinating discoveries delivered straight to your inbox.
