Shreds of dead skin hang from this lizard.


Skin Cell Factory T e bottom of the epidermis is a skin cell factory. It constantly makes new live cells. T ese new cells push up on the ones above them. Aſt er two or three weeks, the cells reach the top of the epidermis and die. T ey become part of your protective shield. It may seem strange to constantly shed skin


cells. You should see what some animals do, though. For example, a snake sheds its entire outer skin all at once. You don’t because your skin stretches as you grow. A snake’s skin doesn’t. So snakeskin can’t grow as the snake grows. Instead, about every six weeks, the snake molts. Its outer skin dies. It splits open. T e snake slithers out. It’s got a brand new, larger skin. It leaves its old skin behind. Animals like frogs and salamanders molt,


too. T eir skin splits in the back. T en the animals use their forearms to pull it off . It’s a little like taking off a T-shirt. Unlike a snake, frogs and salamanders eat their old skin.


This snake’s old skin curls as it peels off.


20 NATIONAL GEOGRAPHIC EXTREME EXPLORER


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