Sifrhippus was a species of horse about the size of an average duck and roamed North America 56 million years ago.
2
Gorillas can catch human colds and other illnesses.
205
Cats recognise the voice of their owner, but never evolved to care.
22
A zoo in China gave a gay penguin couple the opportunity to raise a chick.
11
It has been calculated that a single breath from a mature blue whale can inflate up to 2,000 balloons.
492