The largest rodent in the world is the capybara. Native to South America, capybaras can weigh up to 150 pounds and reach lengths of about 4 feet. They are semi-aquatic animals often found near bodies of water like rivers and lakes, where they thrive in social groups. Capybaras have a unique appearance, resembling giant guinea pigs, and are known for their friendly nature, often allowing other animals, such as birds and monkeys, to coexist peacefully around them. Their adaptations for swimming and grazing on aquatic plants make them an essential part of their ecosystems.