A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
When a male gentoo penguin "falls in love" with a female penguin, he searches the entire beach to find the perfect pebble to present to her.
25
There's a rare breed of pig that looks like a sheep.
14
Parrot parents "name" their children with a signature call.
112
Jellyfish as a species are actually older than dinosaurs and sharks.
383
The Pistol Shrimp can snap its claws together to create a sound of 218 decibels, louder than as supersonic jet at full speed. It only lasts for 1 millisecond. The snapping action also creates a bubble that is greater than 5000 Kelvin, close to the surface temperature of the sun.
21