Sneaky's Daily Did You Know....? - Monsters of the Deep

Scientific research indicates that sharks are the only creatures not to suffer any form of illness. They are thought to be immune to every known disease, including cancer.

A large shark can bite through steel cables. Sharks teeth are constantly renewed. Teeth at the front of the mouth are replaced by new teeth at the back in a kind of conveyor-belt process. Large sharks have up to 1000 teeth.

A Shark can detect one part of blood in 100 million parts of water. The good news in that the chances of being attacked by a shark are 30,000,000 to 1.

The pain threshold of a shark is so high that nothing seems to deter them. Sharks eating rapaciously have been known to continue feeding even after other sharks have attacked and half eaten them. A shark will also eat parts of its own body that have become detached.

Items found inside sharks' stonachs include torpedoes, bicycle parts, crates of drink, car number plates, a horses head, a porcupine, bottles of wine, petrol cans and even a suit of armour.

Although sharks have gills, they can't punp water over them like other fish. So they have to keep swimming in rder to push water over their gills. Consequently sharks never stop swimming - even when they are asleep. If they did, they would drown.

Of over 250 species of shark, only 18 are known to be dangerous to humans.

The embyos of tiger sharks fight each other inside the mother's womb. Only the survivor is born.