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
The chlorine smell in swimming pools is accentuated by the chemical's reaction with impurities (like poop.)
7
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6