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Brown-throated Three-toed Sloth

Bradypus variagatus


Sloths definitely earn their common name. They are the epitome of sssslllloooooowwww. They devote most of their life to sleeping and the rest to eating the leaves of rainforest trees. Three-toed sloths are about the size of a medium sized dog. They are usually pale brown with large patches of dirty white on the lower back and hindlegs. Their fur is long and coarse and just a bit wavy - it is often tinged green from symbiotic cyanobacteria, which provides camouflage - and helps them blend into their tree top habitat.


Sloths prefer to live high in the canopy and only venture to the ground to deficate (approximately once a week!) Rainforest challenge question: What explanation would you give for this behavior?


Sloths can be extremely tricky to find, but once you do they tend to stay put! Be on the look out for large basketball sized lumps in the crooks of trees. Learn how to spot a Cecropia tree you will greatly increase your chances of finding a sloth in the wild - cecropias are one of their favorite food sources and tend to grow in disturbed habitats along side rivers.

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bayucca 8 years ago

Oh, I see my lost comment again! I was quite sure I saved the comment, but it doesn't appear for at least 5 minutes on the screen!! So I wrote it again, I hope I wrote the same thing in both comments... Next time I will save the longer comments before adding it to the post...

bayucca 8 years ago

What's the prize for the challenge??

Sachin Zaveri
Sachin Zaveri 8 years ago

Interesting note and comments thank both AmazonWorkshops & bayucca

AmazonWorkshops 8 years ago

Thanks for adding this additional information bayucca!

bayucca 8 years ago

Sloths are almost exclusively feeding on Cecropia, which need anyway much more time to be digested than other food. Besides they have much larger stomachs with different compartiments than other mammals from the same size, which enlarge digestion time as well. Most functions and metabolic rate are about 50% reduced compared to other mammals. And they sleep most of daytime, however, not as much as it may seem by the name, "only" 9 to 10 hours per day. Note the similar feeding habits of Koalas (exclusively Eucalyptus leaves) and the corresponding sleeping time of up to 20 hours per day! In addition, going down their trees is quite dangerous for sloths due to predation, although the most dangerous predator, the harpye eagle is getting sloths directly from the trees! It must be really a danger to leave the tree since they will abandon their babies which have been fallen from mothers back. But do not forget: Sloths are usually excellent and rapid swimmers! So, perfect adapation of feeding habits and toilet procedures...

bayucca 8 years ago

They almost exclusively feed on Cecropia, they have a very big stomach and this kind of food take anyway much longer time to be digested than other food. All body functions and metabolic rate are reduced compared to other mammals, so economizing is key habit for sloths. Only in water they are rather quick, they are quite good swimmer! These are some reasons for their slow moving habits. But they usually do not sleep for so long time as it might be seemed of its name, only 9 to 10 hours per day, the Koala is sleeping up to 20 hours (note the similar feeding habits: almost exclusively eucalyptus leaves!). Not to forget: Going down from their trees is very dangerous for adult sloths due to predation, however, most dangerous predator is the harpye eagle which gets the sloths directly from the trees. If a baby sloth is falling from a tree they would usually not rescue the baby, because of the danger being predated itself. So, perfect adapation of food, habits and toilet...

Spotted by

Iquitos, Peru

Spotted on Jul 11, 2010
Submitted on Jun 11, 2012


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