There is a sea snail that wears a suit of iron plated armor. It is the only known animal to use iron sulphide as skeletal material.
9
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 ancestor of all domestic cats is the African Wild Cat which still exists today.
12
Two dogs were among the Titanic survivors.
262
Jellyfish as a species are actually older than dinosaurs and sharks.
383