Rodents (L. 'Rodere', "to gnaw") are mammals of the order 'Rodentia', which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents (2,277 species); they are found in vast numbers on all continents except Antarctica. They are the most diversified mammalian order and live in a variety of terrestrial habitats, including human-made environments.

Species can be arboreal, fossorial (burrowing), or semiaquatic. Well-known rodents include mice, rats, squirrels, prairie dogs, chipmunks, chinchillas, porcupines, beavers, guinea pigs, hamsters, gerbils and capybaras.

Most rodents are small animals with robust bodies, short limbs, and long tails. They use their sharp incisors to gnaw food, excavate burrows, and defend themselves. Many rodents eat seeds or other plant material, but some have more varied diets.

They tend to be social animals and many species live in societies with complex ways of communicating with each other. Ferrets (also known as fitchets) are part of 'The Mustelidae' family of carnivorous mammals, including weasels, badgers, otters, martens, minks & wolverines.

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