Sloths take two weeks to digest their food.
243
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
Some lizards, in which the tail is a major storage organ for accumulating reserves, will return to a dropped tail after the threat has passed, and will eat it to recover part of the sacrificed supplies.
13
Dire wolves actually existed, living up to 10,000 years ago before going extinct.
10
Using a remote-controlled camera, biologists caught dolphins getting high by sucking on puffer fish. They were even caught passing the puffer fish around.
23
The oldest known animal in the world was 'Ming' the 405 year old clam, discovered in 2007.
492
The reindeer is the only mammal that can see UV light.
17