Dolphins can rapidly heal from extreme injuries, such as shark bites, and regenerate their original body shape.
19
Rattlesnake mating sessions have been known to last more than 22 hours.
232
Cows can sleep standing up, but they can only dream lying down.
745
A koi fish, named "Hanako", was owned by several individuals over many years and lived to be 226 years old, dying in 1977.
6
Sharks have been on the planet longer than trees.
14
The reindeer is the only mammal that can see UV light.
17