Rodents (from Latin 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. Well-known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters.
Compared to dogs and cats, pet rodents have a shorter life span. Average life spans are 2-3 years for hamsters and gerbils, 1-3 years for mice, 2-4 years for rats, and 5-7 years for guinea pigs. Housing is a critical component of owning a healthy and safe pet rodent.