A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Meysi is one of the world's smallest dogs, measuring in at just 7cm tall, 12cm long, and weighing a meagre 250 grams (only slightly heavier than a hamster!)
11
Crows living in some urban areas drop nuts into traffic to let the passing cars crush them, then they wait for the red lights to stop the traffic so they can grab and eat it.
17
The Basenji dog is the only dog that is not able to bark.
4
Dolphins have names for one another.
18
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
A dork is a whale's penis.
327