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Why is the capybara considered the largest living rodent?

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black-tailed prairie dog — rodent Black-tailed prairie dog (*Cynomys ludovicianus*).

The capybara (Hydrochoerus hydrochaeris) is recognized as the largest living rodent in the world due to its significant physical dimensions compared to all other members of the order Rodentia.1

While mammals in the order Rodentia include over 2,050 diverse species—ranging from rats and mice to squirrels and beavers—the capybara surpasses them all in size. Specifically, the species can grow to approximately 1.3 meters (4.3 feet) in length and reach a weight of up to 79 kg (174 pounds). This substantial mass and length distinguish it as the largest extant species within this vast group of mammals.12