Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
Cats recognise the voice of their owner, but never evolved to care.
22
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
Rats can tell the difference between two human languages.
49
A scorpion can hold its breath for up to 6 days.
19
The first two years of a dog's life are equal to 24 human years.
25