Some older/less efficient worker termites will develop 'backpacks' of toxic chemicals that explode when the termite is threatened. They are essentially used as suicide bombers when the colony is being attacked.
8
Vampire bats adopt orphans, and are one of the few mammals known to risk their own lives to share food with less fortunate roost-mates.
402
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 first known contraceptive was crocodile dung, used by Egyptians in 2000 B.C.
79
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
There's a lizard known as the 'Jesus Lizard' that can run across water.
11