This little piggy… isn’t a pig at all! Guinea pigs, also called cavies, are stout little rodents from various regions of South America. The best known of this family is the domesticated guinea pig (Cavia porcellus) that is commonly kept as a pet, and is broken down into approximately 13 breeds.

It’s believed that the Incas domesticated guinea pigs more than 3,000 years ago, and Spanish explorers brought guinea pigs back from the Andes of South America to Europe, where they were kept as exotic pets. The other members of the genus Cavia can still be found in the wilderness across the continent.

So where did the name “guinea pig” come from? Theories include that one guinea was the cost of one in 16th century England; the name could reflect on the squealing sound the rodents make; or that their meat is similar in taste to suckling pig. It’s also possible that ships leaving the port of Guiana in South America or Guinea in West Africa may have transported the rodents to Europe and the name stuck.

The extended family. Guinea pigs are more distantly related to the rodents in the genera Microcavia, Galea, Hydrochoerus, Kerodon, and Dolichotis; which include other cavies, capybaras, and maras. The greater capybara Hydrochoerus hydrochaeris, for example, is the largest rodent in the world.