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
Cows can sleep standing up, but they can only dream lying down.
745
Elephants are terrified of Bees and actually have a special, distinct vocalization for “Run away the Bees are angry”
49
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
Penguins have a gland above their eye that turns saltwater into freshwater.
12