Sloths are not just found in the rainforest. Just look around and you’ll find them on postcards, bags, T-shirts and mugs, hoodies, wallpapers, and social media – not to mention their role as film stars such as Sid from Ice Age or Flash from Zootopia. Sloths are adored by many for their slowness – praised as healthy and mindful. But since they’ve hardly ever heard of mindfulness and meditation, what’s the real reason why sloths are so slow?
During the Pliocene and Pleistocene epochs, tens of thousands of years ago, many different species of giant sloth roamed the earth. Unlike today, they walked on the ground and dug huge networks of burrows. Some also lived in the sea, and some had armour plates instead of fur. The biggest of these ancient sloths was called Megatherium – it was the size of an elephant! Today there are only six different species, divided into two families, the three-toed and the two-toed sloths. They all have fur covered with fungi and algae, inhabited by insects, and are only about the size of a small dog. Although you might not think so because they spend so much of their lives upside down in trees, sloths are not closely related to monkeys or apes – in fact their closest relatives on earth are anteaters and armadillos!
Sloths live in the tropical rainforests of Central and northern South America, where they hang out in the trees most of the time. They eat leaves and fruit, drink dew drops and river water and, of course, sleep – about 15 hours a day! Their digestion is so slow that they only need to climb down to the “toilet” once a week.
But why are they this slow?
Before sloths were admired for their slowness, it was widely believed that they were just stupid and very lazy animals. Contrary to this assumption, it is a pretty smart way of life, as sloths have been inhabitants of our planet for more than 60 million years. When moving through trees, they typically reach a speed of about 1.2 kilometres per hour. But they have to be very careful climbers because of their very poor eyesight: they are completely colour blind and can see very poorly in both low and very bright light. Instead, they rely on their brilliant sense of smell. Also, because of their extremely low carb diet, they could not move much faster even if they wanted to! As they mainly eat leaves, which are very low in calories, there is not a lot of energy to be gained from them. Not only that, they also have a very low digestion rate. It’s estimated that their digestion process takes between over 150 hours and 50 days! And because of their slow digestion, their stomachs are so full that they cannot eat many leaves every day. Their metabolism is completely adapted to save as much energy as possible. Saving energy is essential for their survival. One of the ways they do this is by constantly changing their body temperature depending on their environment – keeping their body temperature at a certain level is unnecessarily energy consuming for sloths. So, to sum up, sloths aren’t lazy or choosing to hang around – it’s just physically impossible for sloths to be fast!
How convenient that they can use their claws to hang from branches without using any energy. Another advantage of being so slow is that they can avoid predators. Sloths usually move too slowly for jaguars or eagles to spot them.
No wonder so many people adore these unique, slow animals that are so perfectly adapted to their unique upside-down lifestyle. Just one more example is the fact that their oesophagus has a loop – so they can eat and digest comfortably upside down. Sadly, two of the six species of sloths are at risk of extinction – but we humans are to blame, as it is mainly deforestation that threatens their habitat. Fortunately, it is not too late to save these furry animals – there are already many efforts being made to protect them and raise awareness of their situation.
So let’s hope that these amazing and interesting sloths continue to live on our planet for a long time to come – and that, although they never intended it, we can learn from their slowness.
References:
- https://animals.sandiegozoo.org/animals/two-toed-sloth – San Diego Zoo Wildlife Alliance – Animals & Plants, accessed 20/07/2023
- https://www.worldwildlife.org/species/sloth – WWF, accessed 20/07/2023
- https://www.nationalgeographic.com/search?q=sloths&location=srp&type=manual – sloths – National Geographic, accessed 20/07/2023
- https://kids.nationalgeographic.com/animals/mammals/facts/sloth – National Geographic Kids, accessed 20/07/2023
- http://www.edgeofexistence.org/species/pygmy-three-toed-sloth/ – EDGE of Existence, accessed 20/07/2023
- https://slothconservation.org/sloth-o-pedia/ – SlothOpedia, Sloth Conservation Foundation, accessed 20/07/2023
- https://www.nationalgeographic.de/tiere/2018/12/faultiere-sind-langsam-aber-sie-sind-nicht-dumm – Jason Bittel, National Geographic, 26/12/2018
- https://nationalzoo.si.edu/animals/news/why-are-sloths-so-slow-and-other-sloth-facts – Smithsonian’s National Zoo & Conservation Biology Institute, 18/10/2019
- https://slothconservation.org/sloths-move-slow/ – SlothOpedia, Sloth Conservation Foundation, accessed 2/8/2023