A hedgehog, also called a hedgepig or furze-pig, is a small mammal. It has between 5000-7000 spines on its back. There are hedgehogs in Europe, Asia, Africa, and New Zealand. When attacked or threatened, it curls up. Hedgehogs eat insects, snails, frogs and toads, snakes, bird eggs, carrion, mushrooms, berries and melons. Sometimes, hedgehogs will search for earthworms after rainstorms.

Hedgehogs are nocturnal animals and they hibernate between November and March.

Hedgehogs have long spines, or quills, made of keratin. They do not come off easily, unlike porcupines, but in baby hedgehogs, the baby quills drop off and are replaced with adult quills. This is called "quilling". When they are very stressed or sick, their quills can fall off, too. Their quills are not poisonous: they are safe for humans to feel and touch, as they are not very sharp, or harmful.

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