The Basenji dog is the only dog that is not able to bark.
4
Sloths take two weeks to digest their food.
243
Alligator snapping turtles can live for over 150 years. Scientists know this because some of the turtles had musket balls in their stomachs.
271
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
Denmark has twice as many pigs as there are people.
66