It went extinct at least 2 million years ago.
Like the modern great white shark, Megalodon appears to have hunted primarily marine mammals. It may not have been related to the modern great white shark, but a closer relative to the modern makos instead.
The most common fossils of C. megalodon are its teeth. The diagnostic characters of C. megalodon teeth include: triangular shape, robust structure, large size, fine serrations, and visible v-shaped neck. The teeth of C. megalodon can measure over 9 inches in slant height or diagonal length, and are the largest in size of any known shark species.Fossil vertebrae of C. megalodon have also been occasionally found. The most notable example is a partially preserved but associated vertebral column of a single C. megalodon specimen, which was excavated from Belgium by M. Leriche in 1926. This specimen comprises 150 vertebral centra, with the largest centra being 155 cm in diameter. However, scientists have claimed that considerably larger vertebral centra can be expected from C. megalodon. Interestingly, a partially preserved but associated vertebral column of another C. megalodon specimen that was excavated from Gram clay, Denmark by Bendix-Almgeen in 1983. This specimen comprises 20 vertebral centra, with the largest centra being around 230 mm in diameter.
Megalodon's size ranges from 50 feet to 67 feet, and its teeth were 9 inches long. It's not known how large Megalodon actually was, for cartilage doesn't fossilize well. Megalodon's jaw strength was 18.2 metric tons, and it could swim at speeds of up to lost teeth, not unlike modern sharks.
Its hunting process is thought to like that of a great white shark(ambushing prey from below), albeit that Megalodon preyed on much larger prey, such as small whales.
Megalodon shared their habitat and probably competed with Livyatan about 12-13 mya.
In Popular Culture
Megalodon is a very popular creature in pop culture. Megalodons can be found in many cheap science fiction movies. know case of a Megalodon in a movie was in Shark Attack 3: Megalodon. In the movie sightings of a giant shark were witnessed around an island. The giant shark was found to be a juvenile Megalodon. Eventually the parent Megalodon was introduced into the film, but the film makers did not give the parent a constant size throughout the movie. Overall the film was very inaccurate on numerous aspects of a Megalodon. It was also in the movies Mega Shark vs Giant Octopus and Mega Shark vs Crocosaurus, being shown significantly larger than in real life. It's made appearances in the documentaries Jurassic Fight Club, Prehistoric DC and Prehistoric Los Angeles, Sea Monsters, Prehistoric Predators, and had its own show called Sharkzilla during Shark Week on Discovery Channel.
In Jurassic World: The Game, Megalodon can be created as a legendary surface creature in the aquatic park.
In Jurassic Park: Builder, Megalodon can be created in the Aquatic Park section. It can only be created by collecting a rare DNA sample from an aquatic expedition.
It appears in ARK: Survival Evolved.
Gray, the main protagonist of E.J. Altbacker's Shark Wars book series is a Megalodon.
Jurassic Fight Club
Prehistoric DC/Los Angeles
Vertebrate Paleontology; Michael J. Benton