Although many people use the word "rodent" to cover any small mammal, rodents are actually a distinct albeit large group of interrelated animals, some of which can grow quite large. They all have two upper and two lower incisors adapted for gnawing, which grow continuously for the entire life of the animal. Weasels, although they are small and have a low-set body frame commonly associated with rodents, are members of the Order Carnivora, and are more closely related to dogs and cats than they are to rodents.

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