Cows can sleep standing up, but they can only dream lying down.
745
Vampire bats adopt orphans, and are one of the few mammals known to risk their own lives to share food with less fortunate roost-mates.
402
Some lizards, in which the tail is a major storage organ for accumulating reserves, will return to a dropped tail after the threat has passed, and will eat it to recover part of the sacrificed supplies.
13
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
A scorpion can hold its breath for up to 6 days.
19