If a vampire bat goes 2 days without drinking blood, they can die. However, well fed female bats will puke up blood and share it with other bats that they like in exchange for grooming.
13
Cows can sleep standing up, but they can only dream lying down.
745
A scorpion can hold its breath for up to 6 days.
19
A cat rubs against people not only to be affectionate but also to mark out its territory with scent glands around its face. The tail area and paws also carry the cat's scent.
293
There was a bear called Wojtek who was adopted by Polish soldiers during WW2. It carried ammunition, wrestled with soldiers, and drank beer.
40
The Hercules beetle, despite weighing only 100 grams, can lift 8 kilograms, making it one of the proportionally strongest animals in the world.
8
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
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