Flies are deaf.
379
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Black bears are not always black. They can be brown, cinnamon, yellow, and sometimes white.
32
Mosquitoes are attracted to the color blue twice as much as any other color.
28
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
The sloth (a mammal) moves so slowly that green algae can grow undisturbed on its fur!
104
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
A group of geese on the ground is a gaggle, a group of geese in the air is a skein!
19