Geographical Range South America (where first domesticated); introduced worldwide
Habitat Various habitats, associated with human settlements
Scientific Name Cavia porcellus
Conservation Status Common

These shy and gentle rodents are popular as pets the world over. Their hair comes in many different colors and lengths, but in general their body type is the same: a short-tailed, squat body with short legs. Guinea pigs can reach eight inches in length and weigh up to a pound. Guinea pigs’ teeth grow continually. As with other rodents, they have to gnaw on things to keep them trimmed down.

Guinea pigs were originally descended from wild animals in South America known as cavies. Scientists believe that native people domesticated cavies as a source of food as far back as 5,000 B.C. – before the ancient Incas. Later, when Spanish explorers took guinea pigs back to Europe, where they became popular as pets.

There are still wild cavies throughout much of South America, most of them colored a uniform gray or brown. Experts differ over whether these animals are the same species as the domestic guinea pig.