Sloth versus Capybara
The sloth and the capybara, do they have anything in common? What is a capybara, anyway? Aren’t they, like, exotic-looking giant rats?
Capybaras are indeed rodents, the largest in the world, and they are native to South America, so they do share a lot of territory with sloths! They’re both mammals, they both can swim (in fact, the capybara is semi-aquatic), they’re both vegetarians, and they both look great in pictures!
Are sloths and capybaras Related?
Not for about 100 million years. Like so many mammals, the capybara said goodbye to the Xenarthra superorder when Atlantogenata (including manatees, shrews, elephants, and of course our favorite sloths) split from Boreoeutheria (including cats, dogs, rabbits, monkeys, and rodents).
Basically, the easy way to remember if sloths are related to other mammals is: no, unless it’s another Xenarthra. Everyone else split up before the dinosaurs went extinct.
Where do they live?
Both sloths and cavys (the family that includes capybaras, guinea pigs, and wild cavys) evolved in South America, and capybaras live there still. So do many sloths, but sloths also branched out and now live in parts of Central America too!
Are they social animals?
Sloths definitely are not social, but capybaras are very gregarious. In the wild, the biggest group of sloths that seek association with each other is a mother and her baby, but capybaras form groups of 10-40 individuals that may merge into much larger groups during the dry season.
Like sloths, when in heat capybaras make a whistling noise (actually, in sloths it sounds more like a scream or bird cry), but unlike sloths, capybaras only mate in water.
Who sleeps more?
Sloths sleep eight or nine hours per 24-hour cycle, and capybaras also sleep in small naps throughout the day, staying most active around dawn and dusk. The more interesting question is: where do they sleep? Sloths sleep hanging upside down in trees, and capybaras often sleep in the water!
What do they eat?
Both sloths and capybaras are vegetarians, eating a lot of leaves (almost exclusively leaves, in the case of sloths), and capybaras also eat bark, fruit, reeds, and grass. The name Capybara comes from tupí and means “grass-eater”.
Both animals have specialized adaptations to help them digest the tough cellulose found in their diets: sloths ferment it in their large stomachs, and capybaras are autocoprophagous, meaning that they digest their food twice by eating it again after they poop it out once.
How do scientists study sloths and capybaras?
Capybaras do pretty well in captivity, and many studies are conducted on captive animals. Scientists in Japan actually developed an objective classification for how much capybaras enjoy bathing in hot springs (answer: a lot).
Sloths are best studied in the wild, though they are sometimes hard to find, whereas the abundant capybara is easier to spot, observe, and genetically test.
What problems do sloths and capybaras have in common?
Like all wild animals, sloths and capybaras face problems with deforestation and loss of habitat. Capybaras, however, have adapted better than sloths to human encroachment on their environment and can be found in zoos, parks, farms, and even urban neighborhoods.
Are they endangered?
Both capybaras and a few species of sloths are listed by the IUCN as “least concern”, but in the case of sloths, the populations are likely declining significantly, whereas, in the case of capybaras, we are happy to report that they are indeed probably doing very well. The capybara’s ability to live alongside humans has helped them adapt to our changing world.
What can be done to protect both species?
Capybaras are actually doing pretty well, though as aquatic animals they benefit from all initiatives that help protect rivers, lakes, wetlands, and water sources. They are threatened in some areas by hunting.
Sloths need forests to survive, and since rainforests make great watersheds, you can help both sloths and capybaras by saving the rainforest. Both animals face ever-increasing levels of habitat urbanization, and you can also assist by supporting organizations that help them adapt. Perhaps sloths have a thing or two to learn from capybaras－as scientists, we know we do!