Cats recognise the voice of their owner, but never evolved to care.
22
The cat brain weighs about 30g.
167
Sifrhippus was a species of horse about the size of an average duck and roamed North America 56 million years ago.
2
Dire wolves actually existed, living up to 10,000 years ago before going extinct.
10
The oldest known animal in the world was 'Ming' the 405 year old clam, discovered in 2007.
492
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Dolphins sometimes have fun by blowing bubbles and creating rings of air underwater, which they then swim through.
17