8 Weird Facts About Sloths

Who can’t relate to the venerable sloth? They thrive in warm climates, they can spend a whole day just chilling, and, of course, they’re incredibly cute. However, there’s also a lot of wild information you might not know about these fascinating animals.

To celebrate International Sloth Day, we put together eight unusual facts about everyone’s favorite tree-dwelling mammal.

They Are What They Eat

Sloths are known for their slow nature; however, this is primarily due to the relatively low-quality diet they consume. Most sloths eat a regimen of toxic leaves that provide little energy and can take up to a month to properly digest. In fact, if they digested any faster, the toxicity would poison them.

Consequently, sloths need to rest extensively to manage this digestive work. They’ve been known to spend 60 percent of their day just sitting around digesting. And you thought you were lazy after Thanksgiving dinner.

They’re Great Swimmers

Although sloths prefer living in trees, they are also remarkable swimmers. Their strong arms, built for holding onto branches, are well-suited for swimming as well. They can swim three times faster than they can walk on land.

Moreover, their ability to slow their heart rate means sloths can hold their breath for up to 40 minutes underwater.

Pooping Is Life-or-Death

Sloths are creatures of habit. They typically poop once a week and usually in the same spot. Their slow metabolism allows them to go for long stretches between “movements.” However, they must climb down to the forest floor to do so.

Because their weak hind legs result in slow movement on the ground, that’s where they are most vulnerable to predators. No wonder they hold it!

They Have Four-Inch Long Fingers

Although they might look like claws, those long grabby bits are actually their finger bones protruding from the sloth’s paw. The bone is covered in a thin sheath of keratin, the same material our fingernails and hair consist of.

These finger bones grant sloths an acute sense of touch, which is crucial since their eyesight is rather poor.

Their Organs Are Designed to Work Upside Down

Sloths do almost everything in the trees—from sleeping and eating to giving birth! Their long claws are designed for hanging from branches, so their internal organs are anchored to their abdomen to prevent compression of the diaphragm, which would make breathing difficult.

They Can See Behind Their Backs

Thanks to an extra vertebra in their spine, sloths can turn their heads up to 270 degrees in either direction. Biologists aren’t sure why sloths evolved this unique trait; however, the extra range of motion makes it easier to spot predators. Additionally, the specialized bones provide extra neck support when hanging upside-down from trees.

They Have a Surprising Family Tree

The sloth’s closest living relatives are the anteater and the armadillo. All three animals belong to a group known as Xenarthra. These animals’ unique characteristics are largely due to evolving in isolation around 80 million years ago when South America was still an island.

Interestingly, there was even an ancestor to the modern sloth called the Mylodon, which lived around 12,000 years ago. This ancient creature weighed over a ton and could grow up to 10 feet in length.

Their Nasty Fur Could Cure Cancer

The sloth’s slow-moving nature and thick, coarse fur make their bodies prime habitats for various algae and fungi. Biologists believe it’s a mutually beneficial relationship: the algae receive moisture from the sloth’s fur, while the sloth gains added camouflage. Moreover, researchers believe this symbiotic relationship goes further; some sloths have been reported to eat the algae on their fur to supplement their otherwise poor nutritional diet.

In 2014, researchers stated they found strains of fungus that could be used as potential treatments for ailments such as malaria, breast cancer, and Chagas disease.

Where to See Sloths

Sloths live throughout Central and South America. Costa Rica is home to two of the six subspecies of sloth: the two-toed sloth (Choloepus Hoffmanni) and the three-toed brown sloth (Bradypus Variegatus). While these sloth species can be found in the tree canopies all over the country, Parque Nacional Manuel Antonio, Limón, Monteverde, the Osa Peninsula, and Arenal are excellent locations to observe them in their natural habitat.

Seeing Sloths Safely

While it’s tempting to want to hold these lazy little creatures, some studies suggest that human contact can be stressful for sloths. Moreover, such encounters can lead to a marketplace for poaching—tourist dollars exploit the animals and incentivize their capture in the wild. In Costa Rica, it is illegal to hold, pet, or touch sloths (or any wild animal). Therefore, find a knowledgeable guide to spot these amazing creatures in the wild, or choose a reputable wildlife sanctuary or rescue dedicated to the conservation of sloths.