Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
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
Using a remote-controlled camera, biologists caught dolphins getting high by sucking on puffer fish. They were even caught passing the puffer fish around.
23
Lobsters have blue blood.
476
Cows as they are today never existed in the wild and were domesticated from aurochs some 10,500 years ago.
6
Sharks have been on the planet longer than trees.
14