A guinea refers to a guinea pig.
Guinea pigs are a species of rodent that have been domesticated since 5,000 B.C. The domesticated species, Cavia porcellus, is thought to be descended from the Andean Cavia tschudii (or montane guinea pig). These wild relatives can be found in Peru, highland Bolivia, northwestern Argentina, and northeastern Chile. Despite their name, guinea pigs are not related to pigs and do not originate from Guinea.
