Cows can sleep standing up, but they can only dream lying down.
745
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
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Jellyfish as a species are actually older than dinosaurs and sharks.
383
Cat families usually play best in even numbers. Cats and kittens should be acquired in pairs whenever possible!
156