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
When Washoe, the first chimp to use sign language, was told that her caretaker's baby had died, she signed "CRY."
20
Crows living in some urban areas drop nuts into traffic to let the passing cars crush them, then they wait for the red lights to stop the traffic so they can grab and eat it.
17
Cats recognise the voice of their owner, but never evolved to care.
22
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
Parrot parents "name" their children with a signature call.
112