An alligator can go through 2,000 to 3,000 teeth in a lifetime.
268
Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4
Penguins have a gland above their eye that turns saltwater into freshwater.
12
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
Cats are one of the only animals to domesticate themselves and approach humans on their own terms.
20