There are five species of prairie dogs that live in the grassland ecosystems of North America. The black-tailed prairie dog, found in Texas, is named for the black tip on the end of its tail. The prairie dog is in the rodent family, like beavers, squirrels, rats, and porcupines, and has large eyes, a squat body with short limbs, front feet which are used to hold food, and a set of ever-growing, flat incisor teeth at the front of the mouth.