A banana slug can be 6-8 inches and their erect penis can be just as long. Also, their penises emerge from their heads. After sex, banana slugs eat each others penises.
17
The Hercules beetle, despite weighing only 100 grams, can lift 8 kilograms, making it one of the proportionally strongest animals in the world.
8
Cats and dogs can hear ultrasound.
350
Early American humans hunted car-size armadillos and used their shells for houses.
12
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 reindeer is the only mammal that can see UV light.
17
The difference between antlers and horns is that antlers are shed each year and are made of bone while horns are kept for life and are made of living tissue and bone with a sheath that is very similar to human finger nails.
10