A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Sharks, like other fish, have their reproductive organs in their chests.
248
The ancestor of all domestic cats is the African Wild Cat which still exists today.
12
Sloths take two weeks to digest their food.
243
The octopus does not have a blind spot.
273
During World War 1, starving wolves amassed in such great numbers that Germans and Russians had a temporary cease fire to fight off the wolf attacks.
45