The Basenji dog is the only dog that is not able to bark.
4
Some lizards, in which the tail is a major storage organ for accumulating reserves, will return to a dropped tail after the threat has passed, and will eat it to recover part of the sacrificed supplies.
13
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Termites are being researched as a possible renewable energy source as they can produce up to 2 litres of hydrogen from ingesting a single sheet of paper, making them one of the planet’s most efficient bioreactors.
24
Cats recognise the voice of their owner, but never evolved to care.
22