Do sloths have tails?

It’s hard to tell under all that shaggy, mossy, moth-riddled, upside-down growing fur, but lurking at the bottom of every sloth is a cute little tail!

Three toed sloth tails vs Two toed sloth tails

Our three fingered friends have short tails of about 6-7cm (about 2-3 inches). 

three toed sloth skeleton
Chris Dodds [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)]
Two fingered sloths have even littler tails – they’re only 1.5cm – 3cm long (which is only up to just over an inch).

two toed sloth skeleton
By Cliff from I now live in Arlington, VA (Outside Washington DC), USA – Two-Toed Sloth (Choloepus hoffmanni)Uploaded by berichard, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=7607021

Why do sloths have tails?

It’s not like they wag them when they’re happy, or swish them when they’re cross. They don’t even have the energy to use them to swat annoying insects away (not that they’d be much use – they’re too small!). So why do sloths have tails?

I have read that they use their tails to dig holes in the ground to poop. But I haven’t seen any evidence of that, and I wonder if it’s really true.

So perhaps it’s just a hangover from their giant sloth days. Sloths’ ancestors, the giant ground sloths, had massive tails (they had massive everything actually) and they used to use their tails kind of like a third leg – to prop them up like a tripod.

Sloths have obviously evolved very much away from the giant sloth – but maybe their little tails are just a reminder of their long distant past.

skeleton of giant sloth tail
Giant sloth tail