The Largest Rodent Weighs 150 lbs and Eats Its Own Feces

Meet the largest living rodent: the capybara (Hydrochoerus hydrochaeris). The largest adult capybaras can reach up to 150 pounds (68 kilograms) and measure around 4 feet (1.2 meters) in body length.

These semiaquatic giant rodents are neotropical fauna, thriving in the tropical, seasonally flooded grasslands of Central and South America. There, they munch on aquatic plants, grasses and even tree bark.

Capybaras live in large social groups led by a dominant male, who uses scent glands on his nose to mark territory. (Capybaras scent mark everything.) Subordinate capybara males, adult females and young capybaras form a structured community, often resting together near the water to avoid predators.

Like other rodents, capybaras have ever-growing teeth, which they keep in check by chewing on tough vegetation.

One of the most bizarre facts about capybara behaviour? They eat their own feces! This behavior, called coprophagy, helps them digest fiber more efficiently.

When they aren't eating, the world's largest rodents maybe be found lounging in a river or evading jaguars. In some parts of South America, where capybara meat is considered a delicacy, they might also be evading humans.

These powerful rodents, which can weigh up to 70 pounds (32 kilograms), have large, webbed feet that make them excellent swimmers.

North American beavers are also known for their dam-building skills. They use sticks, mud and even their own body mass to create ponds. They spend most of their time gnawing on tree bark and constructing elaborate lodges to keep safe from predators.

Closely related to the North American beaver, the Eurasian beaver, which reaches about 60 pounds (27 kilograms), is another master builder. This species once roamed vast parts of Europe and Asia but was nearly wiped out due to hunting.

Thanks to conservation efforts, they are making a comeback. Like their North American cousins, these beavers rely on tree bark for food and spend much of their lives in water.

The lesser capybara is like the capybara's smaller cousin, weighing around 60 pounds (27 kilograms) and found mostly in Panama and Colombia.

Lesser capybaras are more elusive and less studied, but they share many habits with their larger relatives — such as eating aquatic plants and living in groups.

This rodent looks like a mix between a rabbit and a small deer. The Patagonian mara is native to Argentina and can weigh up to 35 pounds (16 kilograms).

Unlike other rodents, these long-legged sprinters prefer open grasslands and mate for life. They are closely related to guinea pigs and rock cavies, but their lanky build makes them one of the more unique members of the rodent world.

This quill-covered giant roams parts of Africa and Europe, using its spiky defenses to fend off predators. Crested porcupines can reach about 30 pounds (14 kilograms) and are nocturnal foragers that feed on roots, tubers and even bones.

Unlike beavers or capybaras, they are solitary animals that prefer a more secretive lifestyle, hiding in burrows by day and foraging by night.

Last but not least, we have the Gambian pouched rat, a rodent that can weigh up to 9 pounds (4 kilograms). They have a strong sense of smell and are trained to sniff out everything from landmines to tuberculosis.

Native to Africa, they are highly intelligent and sometimes kept as exotic pets. Their large cheek pouches help them store food, much like a hamster, but on a much bigger scale.

We created this article in conjunction with AI technology, then made sure it was edited and fact-checked by a HowStuffWorks editor.