Gorillas can catch human colds and other illnesses.
205
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
Denmark has twice as many pigs as there are people.
66
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
The cat brain weighs about 30g.
167
Alligator snapping turtles can live for over 150 years. Scientists know this because some of the turtles had musket balls in their stomachs.
271
The oldest recorded elephant lived for 82 years.
213