Penguin feathers

The Penguin feathers are waterproof. They keep penguins dry underneath, even while the birds are swimming. If penguins don't keep their feathers in very good shape, they don't stay waterproof. So penguins spend several hours a day preening, or caring for their feathers. Penguins use their beaks, flippers, and feet to preen. For extra protection in the water, penguins spread oil on their feathers. The oil comes from a special gland near their tail feathers.

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