Rodent

Rodents are mammals and can be identified by their teeth. Their incisors (upper and lower) grow throughout their lives. Gnawing on hard material keeps the teeth worn down and sharp. Lagomorphs such as rabbits and hares are often mistaken for rodents. These animals have an additional pair of upper incisors that rodents lack.

The following is a short list of some common rodents:
 * Mouse
 * Rat
 * Squirrel
 * Beaver
 * Porcupine
 * Groundhog