Cows can sleep standing up, but they can only dream lying down.
745
Using a remote-controlled camera, biologists caught dolphins getting high by sucking on puffer fish. They were even caught passing the puffer fish around.
23
Rattlesnake mating sessions have been known to last more than 22 hours.
232
Dire wolves actually existed, living up to 10,000 years ago before going extinct.
10
Cats and dogs can hear ultrasound.
350