Cats recognise the voice of their owner, but never evolved to care.
22
Some older/less efficient worker termites will develop 'backpacks' of toxic chemicals that explode when the termite is threatened. They are essentially used as suicide bombers when the colony is being attacked.
8
Dolphins can rapidly heal from extreme injuries, such as shark bites, and regenerate their original body shape.
19
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
A banana slug can be 6-8 inches and their erect penis can be just as long. Also, their penises emerge from their heads. After sex, banana slugs eat each others penises.
17