A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The oldest recorded elephant lived for 82 years.
213
On some poorly researched trivia lists it is stated as a fact that a pregnant goldfish is called a twit. This is not true as goldfish lay eggs.
71
Nervous dogs wag their tails to the left, and happy dogs to the right (from the dog’s point of view) – and fellow canines pick up on this lop-sided tail language.
10
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Two dogs were among the Titanic survivors.
262
The male seahorse carries babies and 'gives birth' to them instead of the female.
7
The oldest creature ever found was Ming the clam at an admirable 507 years old.
16