There is a sea snail that wears a suit of iron plated armor. It is the only known animal to use iron sulphide as skeletal material.
9
Rattlesnake mating sessions have been known to last more than 22 hours.
232
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
When cats are happy, they may squeeze their eyes shut.
10
Sheep, goats, octopuses, and toads have rectangular pupils.
7
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212