Capybara

The capybara, or greater capybara (Hydrochoerus hydrochaeris), is the largest living rodent on Earth.

These large mammals are native to nearly all of South America, except for Chile. They are semiaquatic herbivores, meaning they live partly in water and eat only plants. They prefer habitats like savannas and dense forests that contain water sources. You can find them near lakes, rivers, swamps, ponds, and marshes.

Because they rely on water, they are highly successful in tropical rainforests and flooded savannas.

To survive in these wet environments, the capybara has several specialized physical traits. They have heavy, barrel-shaped bodies covered in reddish-brown fur. Their underside is usually a lighter yellowish-brown. They possess slightly webbed feet to help them move through water. Their hind legs are longer than their forelegs, and they have three toes on their rear feet.

Their eyes, ears, and nostrils are located near the top of their heads. This placement allows them to see, hear, and breathe while mostly submerged. They are superb swimmers and can hold their breath underwater for up to five minutes. This ability is a vital defense against predators.

Capybaras are highly social animals that thrive in organized groups. Usually, they live in groups of 10 to 20 individuals. These groups typically include two to four adult males and four to seven adult females. During the dry season, when water sources become scarce, these groups can swell to 100 individuals.

Within these groups, males establish social bonds and dominance. They use various vocalizations to communicate, such as barks, chirps, whistles, huffs, and purrs. Males also use scent to communicate. They have a scent gland on their snout called a morrillo. They also have anal glands used for scent-marking objects or other capybaras.

Dietary needs drive many of the capybara's unique behaviors. They are very selective feeders, choosing specific plants while ignoring others. They primarily eat grasses and aquatic plants, but they also consume fruit and tree bark. During the wet season, grass is their main food. In the dry season, they switch to more abundant reeds.

To get maximum nutrition, they practice autocoprophagy. This means they eat their own feces to obtain bacterial gut flora. This process helps them digest cellulose and extract essential proteins and vitamins. They also regurgitate food to chew it again, a process similar to how cattle chew cud.

Because their diet is so tough, capybaras have specialized teeth. Their front teeth and their cheek teeth grow continually throughout their lives. This growth compensates for the constant wear caused by eating abrasive grasses. Their jaw hinge is not perpendicular, which allows them to chew by grinding food in a back-and-forth motion. Like guinea pigs, capybaras cannot synthesize vitamin C. If they do not get enough vitamin C in captivity, they can develop scurvy, a disease that causes gum issues.

History and science have helped us understand the capybara's place in nature. The name "capybara" comes from the Tupi language, meaning "one who eats slender leaves." The scientific genus name, Hydrochoerus, combines Greek words for "water" and "pig."

Famous naturalist Charles Darwin once referred to them as the "water-hog." Modern molecular phylogenetic studies have clarified their family tree. These studies show that capybaras are closely related to rock cavies, a group called Kerodon. This has changed how scientists classify these animals within the subfamily Hydrochoerinae.

In the wild, capybaras face many dangers from predators. They are hunted by South American cats like jaguars, ocelots, and cougars. They are also preyed upon by eagles, caimans, and green anacondas. Because of this pressure, wild capybaras usually live only four years. However, they can live up to 12 years in captivity.

Their population remains stable, though humans sometimes hunt them for meat, hide, or grease. They have also adapted well to urban areas in South America, where they can be found in parks and zoos.