Early American humans hunted car-size armadillos and used their shells for houses.
12
Cats and dogs can hear ultrasound.
350
When a male gentoo penguin "falls in love" with a female penguin, he searches the entire beach to find the perfect pebble to present to her.
25
Sergeant Stubby was the only war dog to be promoted to sergeant through combat in WWI. He saved his regiment from surprise mustard gas attacks, found and comforted the wounded, and even once caught a German spy by the seat of his pants, holding him there until American Soldiers found him.
16
The most expensive dog in the world is the Tibetan Mastiff; worth $1.5 million.
2
Unsinkable Sam (nickname of a German ship's cat) who served on 3 warships, one German, two British, all sank in action. The cat survived each sinking, floating away on wooden planks to rescue.
19
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14