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
The reindeer is the only mammal that can see UV light.
17
Sharks, like other fish, have their reproductive organs in their chests.
248
It has been estimated that a bite from a grizzly bear can crush a bowling ball.
11
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
Nervous dogs wag their tails to the left, and happy dogs to the right (from the dog’s point of view) – and fellow canines pick up on this lop-sided tail language.
10