The Megalodon
The Megaladon (Big Tooth)

What not many people realise, is that 95% of the ocean is left unexplored.
Who knows what could still venture beneath our feet?
(next bit taken from Wiki)
The megalodon (pronounced /mɛɡlɑːdɒn/ or meg-la-don; meaning ‘big tooth’ or in Greek as μέγας ‘οδόντος) is a giant prehistoric shark that probably lived between about 16 to 1.5 million years ago, and was the apex predator in its time. It is recognized as the biggest known carnivorous fish to have ever existed. It is often termed the “megatooth shark”. The classification of this shark is currently under dispute and a new genus has been proposed for this shark. Fossil records reveal that the megalodon fed on large animals including the early whales.
Some cryptozoologists argue that this shark might still be alive in this modern age, probably living in the deep waters, and often cite the examples of coelacanth and megamouth shark to support their claims. But such beliefs are considered to be false and lack sufficient credibility. Still, C. megalodon has left a lasting impact on the minds of the people around the world, as a highly fascinating monster, which is evident from the popular culture.
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