Hippos can open their mouths 180 degrees

If you have never had nightmares about a hippo chasing you through the African savanna, get ready to have those tonight! The Hippo can open its massive mouth at a 180-degree angle, which is half the circumference of a circle. On top of being able to open its mouth to such a wide degree, the hippo also has canine teeth that are the length of 2 rulers and the jaw strength to bite a human in half. Oh ya, and you cannot outrun them, as they can move at speeds of over 30km/h on land.