Dolphins sometimes have fun by blowing bubbles and creating rings of air underwater, which they then swim through.
17
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
An average cat has 1-8 kittens per litter and can have 2-3 litters per year. During her productive life, one female cat could have more than 100 kittens. A single pair of cats and their kittens can produce as many as 420,000 kittens in just 7 years.
10
Sifrhippus was a species of horse about the size of an average duck and roamed North America 56 million years ago.
2