The prehistoric Megatherium sloth was around the size of an elephant, weighing between four and seven tonnes.
Sloths are clumsy on land, but amazing swimmers.
When in search of a mate, female sloths let out a blood-curdling scream.
Their favourite food is hibiscus flowers.
Three-toed sloths can turn their heads 270 degrees.
Sloths only natural defence against predators are its claws.
These sluggish tree-dwellers move so slowly that algae can grow on their coats.
Sloths spend most of their lives in the trees – they even mate and give birth up there!
Sloths prefer sleeping while curled into a ball in the fork of a tropical tree.
Adelaide Zoo is home to the oldest known two-toed sloth in the world.