Imagine a fish about fifteen metres long with a jaw full of teeth as long as your hand... That's the Carcharodon Megalodon, or rather, it was...

The Elders called them 'glossopetra', in the belief that they were the tongues of petrified snakes. Bernard Palissy, a 16^th century French scientist, was one of the first to suggest that these stones were in fact the teeth of shark-like fish. In the middle of the 17^th century, a Danish scientist, Niels Stensen, came to the same conclusion which he presented in a little book in 1667: "Canis Carchariae Dissectum Caput". In it he described the similarities between modern shark teeth and these "stone tongues" which for centuries were extracted from the cliffs of the island of Malta. For him, these teeth belonged to a giant shark now extinct. The Swiss naturalist Louis Agassiz made this discovery official in 1835 by describing and naming this shark Carcharodon Megalodon (shark with big teeth).

This huge shark, cousin of the white shark (some say closer to the mako shark) presumably appeared during the Tertiary Period at the beginning of the Miocene Epoch (- 24 million years to - 5 million years) and died out about 1.5 million years ago at the end of the Pliocene Epoch. All that remains of its time spent in our oceans are fossilised teeth of impressive size which can be as big as 20 centimetres high. Only a few fossilised vertebrae have been found, as the cartilaginous nature of the skeleton did not help its preservation.

From the size of its teeth, it is believed that the Megalodon was three times as big as the white shark and could attain a length of 15 metres for a weight of 20 to 25 tonnes. By comparison, the biggest white shark known until now was caught in the Mediterranean near Malta and measured 7.10 metres.

The sites where fossilised teeth have been found lead us to believe that the Megalodon favoured the warmer waters of the oceans. The big marine mammals (cetaceans), plentiful during the Miocene Epoch, were the giant sharks' prey. The fossilised bones of dolphins or whales are often found near Megalodon teeth.

From this observation, scientists believe that the Megalodon's disappearance is related to the climatic change that occurred in the middle of the Pliocene Epoch: it is presumed that the Ice Age the Earth experienced seriously disrupted the life of this shark used to warm waters. Moreover, it is possible that the big marine mammals moved to colder waters where the Megalodon could not follow. Whale fossils discovered in Antarctica allow us to assert that they began living in these waters during the Pliocene Epoch.

New Caledonia has a few underwater sources which are exploited by the company TUI II of Noumea. The teeth are fished up in the south of New Caledonia using a dredge at a depth of 300 meters.