Webbed foot of a capybara. The Capybara, Hydrochoerus hydrochaeris, is the largest rodent on Earth. They live semi-aquatic lives, foraging on vegetation in and around the water. They can grow to a mass of roughly 100 pounds. They have webbed toes for swimming. Many species prey on Cabybara, including jaguars, pumas, caiman, and humans. This specimen was photographed in Amazonian Peru in 2010.