Hedgehogs are small, spiny, mammal species, widely distributed in Europe, Asia, and the Americas. They are known for their adorable appearance, especially their round, prickly bodies, and the ability to roll into a tight ball when predators are nearby. Hedgehogs have a unique physiology and a very high metabolism, consuming a great deal of food each night. Despite their prickly appearance, hedgehogs are not harmful to humans and make interesting pets.