The Life of Mammals -- Fascinating Facts

- Under all that white fur, a polar bear's skin is black.

- Giraffes have blue tongues.

- Mandrills have red bums to help them follow one another through the forest.

- A sea otter uses rocks to crack open shellfish, and keeps its favourite one under its armpit.

- A gibbon's arms are so long it can touch its toes without bending over.

- Elephants never stop growing; happy elephants make a low rumbling noise like purring.

- Thirty pygmy shrews weigh the same as one golfball.

- An adult hedgehog has 7,000 spines and as many as 500 fleas.

- Hedgehogs have been around for 15 million years, so were trundling around before sabre tooth tigers.

- A beaver can swim half a mile underwater on a single gulp of air.

- Male platypuses have poisonous spurs. Their venom causes such excruciating pain that it can't even be relieved using morphine.

- Numbats sleep in hollow logs and stuff their bums in the end to act like a cork so that predators can't pull them out.

- Which mammal has the longest claws? A lion? No -- a giant anteater. Its claws are 10cm long.

- The slow loris has teeth that are slightly spaced apart sothat they act as a grooming comb.

- The blue whale is 33.5m long - the same as 18 scuba divers with flippers.

- The biggest mammal, the blue whale, weighs 90,000,000 times more than the smallest, the pygmy shrew.

- An aardvark can dig a 4-foot burrow faster than 6 men with shovels.

- Kangaroos lick their forearms to keep cool.

- Gorillas are eight times stronger than humans. If gorillas took part in a weightlifting contest, they'd lift 2,128kg to a human's 266kg.

- Male grey kangaroos are called 'boomers' and females 'flyers'.

- The kangaroo's family name is 'macropodidae' which means 'big feet'.

- Sperm whales dive to depths of 2,400 metres or more -- six times the height of the Empire State Building.

- Burrowing marsupials such as the wombat have pouches that face backwards so that soil doesn't get thrown into them while digging.

- The sinews and tendons in a caribou's legs make a loud clicking noise when they walk.This helps the herd know where everyone is.

- Beavers have orange teeth.

- A sperm whale has a brain six times bigger than a human's.