A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Female kangaroos have three vaginas.
2
The Platypus used to be considered a myth like Bigfoot and the Yeti.
18
When a drone bee mates with a queen, its ejaculation is so powerful that it can even be heard by the human ear.
5
Sheep, goats, octopuses, and toads have rectangular pupils.
7
The two oldest cats on record lived to 38 and 34 years old, both were owned by the same owner and lived off a diet of bacon, eggs, broccoli and coffee.
12
A koi fish, named "Hanako", was owned by several individuals over many years and lived to be 226 years old, dying in 1977.
6
Dolphins can rapidly heal from extreme injuries, such as shark bites, and regenerate their original body shape.
19