If a vampire bat goes 2 days without drinking blood, they can die. However, well fed female bats will puke up blood and share it with other bats that they like in exchange for grooming.
13
Cats and dogs can hear ultrasound.
350
A newborn Chinese water deer is so small, it can (almost) be held in the palm of a hand.
13
The octopus does not have a blind spot.
273