Bats sleep 18-20 hours per day.
5
There's a rare breed of pig that looks like a sheep.
14
Mosquitoes prefer certain blood types, and people with the “O” blood type are more likely to get bitten.
12
Dolphins sometimes have fun by blowing bubbles and creating rings of air underwater, which they then swim through.
17
When Washoe, the first chimp to use sign language, was told that her caretaker's baby had died, she signed "CRY."
20