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
During World War 1, starving wolves amassed in such great numbers that Germans and Russians had a temporary cease fire to fight off the wolf attacks.
45
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
Dolphins can rapidly heal from extreme injuries, such as shark bites, and regenerate their original body shape.
19