There are two main sloth species. The two-toed sloth and the three-toed sloth. Both species have three toes on their hind legs, but the difference comes in their front paws. The toes are actually more like fingers as they are distinguished only on their front limbs.
Algae can grow on the sloths fur providing them natural camouflage in a dense rainforest. Sloth fur is extremely absorbent which makes it easy for algae to grow. Notice how the sloth fur has shades of green on the arms and back of the head. This occurrence is of a symbiotic nature. It's perfect for this slow moving rainforest critter to blend in with the bark of the trees and the greenery of the leaves and vines. Sloths are the slowest mammal in the world making it easy for algae to grow.
Unique Sloth Vertebrae
Sloths have an extra vertebrae at the bottom of their neck which allows them to turn their head 270° which allows them to have a wide field of vision to spot predators. This flexibility serves as a defense mechanism. Most mammals in the animal kingdom have a seven-vertebrae neck, but sloths can have as many as ten vertebrae. A scientific discovery by the University of Cambridge in England found that "the part of the skeleton which they had long believed to be part of the sloth rib cage is, in fact, analogous to the bottom of the mammal’s “neck.” Meaning the bottom neck vertebrae of sloths are similar to the top rib cage vertebrae of other mammals.
Sloths spend about 90% of their life hanging upside down. Because sloth organs are attached to their rib cage, they won't put stress on their lungs and can breath normally despite their hanging position.
Why Sloths are Slow & their Diet
Sloths move very slow. In fact, sloths move slower than any other mammal on the planet. They typically will not travel more than 125 feet in a day and they crawl only 1 foot per minute on the rainforest floor.
Sloths typically have a diet that is poor in nutrients with low calorie intake which makes them sluggish. To combat this, they have a slow metabolic rate to help with this low calorific intake says Camila Mazzoni of the Leibniz Institute for Zoo and Wildlife Research in Germany.
Sloths typically eat leaves, buds, and tender shoots although they are known to additionally eat insects and birds to supplement their diet. Sloth stomachs have multiple compartments which makes it easier for them to break down tough fibrous plants. It is a slow process and can take a month to digest one meal. Sloths can carry up to a third of their body weight in urine and feces and only defecate once a week. It's actually the only reason sloths climb down from the safety of the rainforest trees.
Becky Cliffe, a British zoologist who works at Costa Rica’s Sloth Conservation Foundation, says it is only when you see sloths in the wild that you truly appreciate just how slow they are. “You know they move slowly, but then you look at one and every part of their body – when they turn their head, or even when they blink – it’s all done so slowly. You have to spend a lot of time out in [the] field to see one.” While sloths are slow and can sleep up to 20 hours a day, most wild Costa Rican and South American sloths only sleep eight to nine hours a day.
Additionally, sloths have poor eyesight. They have a unique eye condition: rod monochromacy. This condition means they don't have cone cells in their eyes. Therefore, sloths are color blind, see poorly in low light, and are blinded by harsh sunlight. Instead sloths rely on their strong sense of smell and spacial memory to get around find food. Because sloths are almost completely blind, they are sluggish in their movements across the rainforest canopy.
Sloths natural predators are harpy eagles and jaguars. Both predators have keen eyesight and can kill sloth with one menacing blow. To combat this, sloths rely on their camouflaged fur and lack of body odor to give away their location to predators. Because sloths don't have natural body odor, it's easier for them to evade predators in the wild.
Sloths are Strong and they're Great Swimmers
Cliffe has spent years watching sloths in the Costa Rican rainforest which has provided insight into this unique mammals nature. “They don’t jump and they don’t run. But they do have the most incredibly strong arms. If a human and a sloth had an arms wrestle, the sloth would definitely win.”
The strong forearms of a Sloth make it a great swimmer. Though sloths typically reside in the rainforest, but they love swimming. They can even hold their breath for up to 40 minutes at a time. Sloths suppress their metabolism to make their heart rate drop so they don't use up as much oxygen. Additionally they are up to three times faster in the water than when moving on land or in the trees.
The facial shape of a sloth's face gives it the appearance of a constant smile. It can be deceiving because even though the sloth may seem to display a sense of joy, the animal could be experiencing pain or anxiety. Though we love photos of sloths smiling and may want to take photos with them as a tourist, we need to understand that they are wild creatures.
Things to Remember
Sloths are amazing creatures and we love to see them thrive. Find more information on how to protect them at Slothconservation.com! A percentage of every purchase on Slothshirts.com goes toward supporting conservation efforts to save sloths in the wild. Always remember, Sloth Shirts are Forever <3