Humans do it for 8 hours. Horses do it for 4. Koala bears do it for as much as 22 hours a day.

Sleep.

Most animals on this planet need it, and we still don’t understand why. Carnivores do it more than herbivores…it’s believed the giraffe sleeps the least.

Some insects don’t sleep. Bullfrogs don’t. Sea urchins don’t. Jellyfish don’t. Baby dolphins take their first nap at the age of one month (I can hear human parents groaning already).