Jellyfish as a species are actually older than dinosaurs and sharks.
383
A scorpion can hold its breath for up to 6 days.
19
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
When cats are happy, they may squeeze their eyes shut.
10
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Squirrels forget where they hide about half of their nuts.
698
A zoo in China gave a gay penguin couple the opportunity to raise a chick.
11