A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Urechis unicinctus is a species of marine spoon worm that is widely referred to as the ‘penis fish’.
2
In 1955, the citizens of São Paulo were so upset with their government that they elected a rhinoceros named Cacareco (meaning rubbish) to the city council in protest, with over 100,000 votes.
18
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
Domestic pigs average a top speed of about 11 miles per hour.
182
The Basenji dog is the only dog that is not able to bark.
4