If Megalodon sharks were still alive today, they would be a breathtaking sight. They were the largest sharks ever — up to three times longer and thirty times heavier than today’s great white sharks. Or as a shark scientist quoted by National Geographic put it, “A great white is about the size of the clasper, or penis, of a male Megalodon.”

Their teeth averaged 3 to 5 inches — and were sometimes more than 7 inches long. They were top-level predators that hunted and ate whales, using their huge teeth and powerful jaws to bite off the tails and fins of their prey.

No wonder people hope to someday spot Megalodons swimming around. Scientists, though, say that’s not going to happen. According to the fossil evidence, megalodons have been extinct for about 2.6 million years.

Fake documentaries

discovery channel megalodon promo

Discovery Channel – Megalodon: The Monster Shark Lives

Despite the evidence, many people hold onto the belief that living Megalodons still exist somewhere in the deep ocean. You can blame the Discovery Channel for much of that false hope. The network aired a series of popular programs as part of its Shark Week events claiming that a “50-ton monster” Megalodon might be alive today. The programs appeared to be documentaries, but they were really fictional “mockumentaries” that used fake photos, computer-generated images and special effects, and actors portraying scientists.

The programs, though fake, fooled a lot of people who were reasonably expecting the channel’s programming to be factual and who could easily have missed the tiny disclaimers the channel placed at the end of the programs.

Claim that recent teeth have been found

Those who want to believe in living Megalodons say that teeth found in the South Pacific in the 1950s appear to be from Megalodons that were alive as recently as 11,000 years ago. If that claim were true, then Megalodons could not have gone extinct millions of years ago. That claim fails, though, because the method scientists used in the 1950s to determine the ago of fossils is now known to be invalid. More accurate contemporary testing methods show that the age of teeth range from 5 million to 23 million years old.

New Caledonia Megalodon Teeth

No one has seen them

No one has seen a living megalodon. It’s true that’s not definitive evidence, per se. As Donald Rumsfeld famously said, “Absence of evidence is not evidence of absence.” Yet it seems like common sense that if Megalodons existed, someone would have seen them.

People who believe that Megalodons are not extinct seize onto the idea that the creatures might be swimming around in the deepest part of the oceans. The oceans are huge, they say, and there is a lot we don’t know about what goes on there, way deep down near the bottom.

The problem with that argument is that the deep waters of the ocean are very cold, and the evidence shows Megalodons were warm-water animals.

Megalodons lived in warm, shallow water

Fossil evidence, especially Megalodon teeth, shows that the sharks lived in warm, shallow water and they nursed in coastal areas. If they were still around and living in their usual habitat, we would have seen them.

It’s not easy to miss 50-foot creatures that attack whales and other large sharks. If nothing else, whale watchers would have seen Megalodons hunting their prey and would have spotted bite marks too large to have been made by any other creature on whales’ fins. But no one has ever seen that.

But what if they evolved to live in deep water?

People who believe that Megalodons are still here have a counterargument ready.  OK, they say, maybe Megalodons used to live in warm, shallow water way back when. But what if they evolved to be able to live in cold, deep water? What if they became smaller and better adapted to the cold? Then they could be alive and just hidden from our view.

The problem with this argument is that the warm, shallow water environment and the cold, deep water environment are drastically different. They are as different from each other as a rain forest environment is different from a tundra environment. Just as an animal adapted to live in the rain forest could not survive in the tundra, so the Megalodon, adapted to survive in warm water, could not survive in the deep ocean’s cold waters, where the temperature hovers around the freezing point. If megalodons did evolve to be able to survive in the deep ocean, the changes would be so great that they would no longer be Megalodons. They would have become a different species.

Besides, even if they really did live in deep water, we most likely would have seen signs of their existence. Giant squid, for example, live in deep water, but pieces of their bodies and tentacles have washed up on our shores. The squid have even been filmed. If a squid can’t hide from us, then it’s not likely that the even larger megalodon would be able to escape our notice.

Extinct for 2.6 million years

A recent study applied a new mathematical model to the fossil record to show that Megalodons have been extinct for about 2.6 million years. The scientists’ model had previously only been used to determine the time of recent extinctions, such as the extinction of the dodo bird. This was the first time the model had been extended to date an extinction that happened millions of years ago, and the model shows great promise for dating the extinctions of other species that died out a long time ago.

Things are not looking good for top predators. At some point, other large sharks may share the Megalodon’s fate. Out of all the vertebrates, sharks are now the most likely to go extinct. That’s sharks in general. For shallow-water dwelling large sharks, in particular, the news is even worse. They are the most likely of all marine animals to face extinction.

The wish that Megalodons were still alive remains just that — a wish. Despite the claims of the mockumentaries, the real evidence shows that megalodons have long been gone. We can’t undo an extinction that occurred millions of years ago. But we may be able to save some species now, at least those species whose existence is threatened by human activities. For some of those species, it may not be too late.