Brown-throated three-toed sloth


Sloths are avid herbivores. As such, they can turn their head around 180° to reach every leaf or fruit possible. They have a very specific diet. In the Colombian Caribbean region their main food source is the trumpet tree (Cecropia peltata), a 5 to 30 m tall tree with big palm-like leaves. Occasionally they are also found, eating the flowers of Pseudobombax septentatum, a big neotropical tree. After they are born, baby sloths learn their preferred diet by picking up the remains of leaves from their mother’s lips.

Sloth eating, Jardín Botánico “Guillermo Piñeres”

Sleeping position

In search of a sleeping place, they look for a branch fork in which they can sit facing the trunk, wrapping their arms around themselves, with their head resting on their chest. They hold onto the tree with only their feet around the trunk. In the rain they adopt the same position as they do for sleeping. They do not actively seek shelter during thunderstorms. After heavy rains they can be observed completely soaked. Unlike most other animals in the wild the parting on their hair is located on their belly and not on the back. This ensures simple water draining if they stay in the rain.

Sloth sleeping in a trumpet tree, Jardín Botánico “Guillermo Piñeres”

Slowest animal on earth

Sloths are incredibly stagnant and slow creatures but this has a very interesting reason. They have the most lethargic metabolism of any animal in the world. Meaning every physical and chemical process that uses or converts energy in their bodies, like respiration or digestion, are immensely slow in comparison to nearly every other terrestrial animal. This allows them to eat only about 190 grams of leaves every day which translates roughly to about 3 leaves. 

We humans use most of the energy we consume to regulate our body temperature and for vital functions like the regeneration of cells. Sloths slow down these processes immensely to use as little energy as possible. As a result of this they sleep up to 18 hours a day to conserve every ounce of energy they can. 

They are also strongly dependent on a tropical climate since they would require way more energy to maintain their temperature. Their habitat in the tropics and subtropics of the Americas allows them to not waste the energy they would otherwise need.

Sloth resting and scratching itself, Jardín Botánico “Guillermo Piñeres”

Camouflage and predation

There is almost no other animal that is so well-adapted to arboreal life as sloths. They developed some fascinating physical characteristics. Their long arms help, reaching twigs or branches that are far away and their short strong legs lock them in place wherever they need to. Their hook-shaped claws are sharp to allow them to get a firm grip, even on slippery bark. After grabbing a branch their tendons seal off and their hands and claws almost become immovable which lets them hang on a single arm for more than 10 minutes.

Since Sloths are frequently hanging upside down, they developed special valves that prevent their blood from clotting in their head. Because of that, being upside down does not pose a challenge to them like it would to us humans. 

With the color of their fur and algae growing on their back they are also masters of camouflage. In combination with their sluggishness, they are almost perfectly protected against predators of any kind. Many of the animals that pose an imminent threat to the sloth, like the ocelot or the harpy eagle hunt by monitoring movement or color so the sloth can elude them almost perfectly by doing basically nothing.

Mutualism with moths

Sloths are not clean animals. In their fur live a wide variety of bacteria, insects and fungi. Many of which are parasites, but there is also a very interesting species of moths. These so-called sloth-moths are in a symbiotic and mutualistic relationship with their hosts. Every 7 or 8 days three-toed sloths descend to the ground and dig a small hole for their excrement. The moths use this moment to lay their eggs inside the dung. After hatching they leave the dung in search of the nearest sloth. When their life comes to an end their body provides enough nitrogen to the sloth’s fur that algae can grow in small cracks along the hair on their back. The growing algae is then used to camouflage and even aid their diet with the fat-rich algae.

Moths living in the fur of sloths, Jardín botánico “Guillermo Piñeres”