One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
Lobsters have blue blood.
476
The sound of a tiger's roar can travel a distance of up to 2 miles (~3 km).
255
Mosquitoes prefer certain blood types, and people with the “O” blood type are more likely to get bitten.
12
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
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
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6