By Emma Wilson Fans are convinced a giant megalodon shark “still exists” after spotting a chilling clue in a documentary. The prehistoric monster, which scientists estimate lived around 20 million years ago, measured around 70ft in length and weighed up to 70 tonnes, and is not only the largest shark in history, but is the largest fish that has ever lived. While experts believe the megalodon is extinct, some eagle-eyed viewers of a Discovery Channel documentary think otherwise. A clip from a Discovery Channel documentary, Megalodon: The Shark Lives, which originally aired in 2013, has resurfac…
