Compared to other organs, skin may seem kind of simple and boring. But it's actually pretty complex.
Readers of detective fiction knows one thing fingerprints are good for, their unique patterns. Why have we evolved such convoluted fingertips and why so useful?
The top layer of skin, called the epidermis, is very thin–only 1/10 of a millimeter at most. This is where cells constantly divide from the base layer and move up to the surface to be sloughed off.