Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Dire wolves actually existed, living up to 10,000 years ago before going extinct.
10
A koi fish, named "Hanako", was owned by several individuals over many years and lived to be 226 years old, dying in 1977.
6
Sharks, like other fish, have their reproductive organs in their chests.
248
There was a bear called Wojtek who was adopted by Polish soldiers during WW2. It carried ammunition, wrestled with soldiers, and drank beer.
40