The Basenji dog is the only dog that is not able to bark.
4
A puppy is born blind, deaf, and toothless.
16
It has been calculated that a single breath from a mature blue whale can inflate up to 2,000 balloons.
492
The sound of a tiger's roar can travel a distance of up to 2 miles (~3 km).
255
Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4