A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
A koi fish, named "Hanako", was owned by several individuals over many years and lived to be 226 years old, dying in 1977.
6
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
The Basenji dog is the only dog that is not able to bark.
4
Sandy, an African Penguin, has been in 'love' with her keeper at the Nuremburg zoo since 1996.
34
Sheep, goats, octopuses, and toads have rectangular pupils.
7
Urechis unicinctus is a species of marine spoon worm that is widely referred to as the ‘penis fish’.
2