The Truth About Megalodon: The World’s Largest Extinct Shark

By now, I’m sure you’ve heard of Megalodon. If you haven’t heard of Megalodon, then you might have seen an advertisement for The Meg, an unexceptional action film starring Jason Statham and Megalodon as the film’s titular antagonist. Moreover, if you aren’t aware of The Meg’s existence (you’re not missing much), I can guarantee that you know what a shark is and have probably pondered the existence of a really big shark. Indeed, that’s what Megalodon is: a really big shark. A shark that, amongst other things, is the largest shark of all time; the largest fish of all time; a dominant predator that ruled across the Oceans of the world for well over 15 million years; and the record holder for largest bite force of all time. Perhaps most importantly, Megalodon is the true star of a wacky Jason Statham flick, Either way, I’d like to share some basic facts about Megalodon.

A Shark Unlike Any Other

Did I mention that Megalodon was really big? While the true size of Megalodon has always been unclear due to a lack of proper specimens (more on that later), the range of possible Megalodon sizes is astronomical. Let’s play the compare-the-size-of-the-dead-thing-to-the-living-thing game. The Whale Shark, which is the largest living shark species and the largest living fish, has a maximum size of about 10 meters and weight of 20 tonnes. Pretty big, right? Well, the conservative size estimate of Megalodon is 13 meters, easily dwarfing the Whale Shark by some 3 meters. The most widely accepted estimate entails a size of around 16.5 meters long and a whopping weight of 59 tonnes, almost triple the weight of the Whale Shark. The largest size estimates entail a 20-meter-long shark that would have weighed around 100 tonnes. One hundred. While the 100 tonne estimate is kooky and definitely too large, the realistic 60 tonne estimate still makes for a monstrous shark. In fact, Megalodon is the largest known fish of all time; only the Jurassic fish Leedsichthys comes close at an approximate 16 meters; but even then, its size is based on fragmented remains. As such, Leedsichthys was likely a fair bit smaller than Megalodon. To put it bluntly, Megalodon wasn’t just THE really big shark; it was also a really big fish.

To emphasize the size of Megalodon, below this text are two pictures. One is of me with the jaws of a modern shark species (right) and the other one is of six fully grown men within the jaws of Megalodon (left). Pretty big, right?

Mega-Predator Requires Mega-Prey

The size of Megalodon is incredibly impressive when considering what it ate to become so large. Other giant fish, such as the Whale Shark and Leedsichthys, are filter feeders. To eat, they simply open their mouths and gobble up massive amounts of microscopic plankton, far and away one of the most efficient and effective feeding methods for large aquatic animals. On the other hand, Megalodon had a far larger choice of prey: whales. The evidence is clear, as hundreds of whale bones from across the world contain large marks and gouges, all of which can be attributed to Megalodon bites. The location of the bites, which are concentrated on the flippers, demonstrate the deadly pattern utilized by Megalodon; bite off the flippers and leave its prey stranded in the open ocean without any possible means of locomotion, defenseless from further attack. The bite force of Megalodon – a whopping 40,000 pounds per square inch – would make short work of any whale’s skeleton. That bite force was by far the greatest of any animal or fish ever. For Megalodon, biting through a whale flipper would be akin to a human savouring a bowl of pudding.

Whales may have been the primary target of Megalodon, but they certainly weren’t the only prey on the menu. Other prey items would have included, but were not limited to: dolphins, seals, sea lions, sea turtles, manatees, smaller sharks, fish, the aquatic sloth Thalassocnus and the tusked whale Odobenocetops. To be blunt, Megalodon would have eaten everything and anything it came across; assuming it was hungry, of course.

Teeth Scattered All Over the World

For extinct whale species, there was no way of escaping Megalodon. The teeth of Megalodon have been found in dozens of countries across the globe, with specimens known from both adult and juvenile individuals. Megalodon teeth are found on both coasts of the Atlantic and Pacific oceans, some locations around the Indian Ocean and on the shores of the Mediterranean Sea. In addition to being found across the world, the fossils of Megalodon also encompasse a very large amount of geological time. The oldest fossils of Megalodon are dated to the start of the Miocene epoch, some 23 million years ago, and the youngest date to 3.5 million years ago during the Pliocene epoch. Since Megalodon teeth are very common up until the end of the Pliocene, it is not hard to infer that Megalodon truly had global dominance over the world’s oceans. Or did it?

Killer Competition

About that global dominance thing: Megalodon wasn’t the only giant marine killer of the Miocene. In a surprising twist, the major competitor Megalodon faced in hunting whales was, well, other whales. Not just any whales however; these were giant toothed whales, relatives of the modern sperm whale that rivaled Megalodon in both size and ferocity. Chief amongst these predatory whales was Livyatan, appropriately named after the legend of the leviathan and inspired by the whale from Herman Melville’s epic tale, Moby Dick. At 17 meters long, Livyatan rivaled even the largest Megalodons in size, making it a formidable opponent to the shark. Livyatan possessed multiple adaptations that would have assisted in hunting, including massive teeth that were amongst the largest teeth for any animal known, pack (pod?) hunting behaviours, a broad skull that could be used as a battering ram, and an advanced sense of echolocation (a form of sonar that could help detect prey in low-light condition). It is fair to assume these two mega-carnivores would have encountered each other as well, since they lived in the same regions at the same time. The idea of Livyatan vs Megalodon has been the subject of much debate amongst paleo-nerds in recent years, with sides being formed for each species. If the confrontations between Great White Sharks and Killer Whales in the present give any indication as to who the victor would be, then perhaps Livyatan was the superior killer. Truth be told, I feel sorry for the poor aquatic animals of the Miocene that had to share the waters with two mega-carnivores…

The Truth About Megalodon….

What is the truth about Megalodon? It is in the title, after all. Here it goes: truth is, despite being one of the most famous extinct animals of all time, Megalodon is also one of the least understood. Like all sharks, the skeleton of Megalodon was made out of cartilage, which unfortunately doesn’t fossilize. As such, paleontologists have to work with teeth and the occasional vertebrae, which presents many gaps in understanding Megalodon. Using teeth to make size estimates doesn’t always produce accurate results, and that’s why it’s difficult for paleontologists to be completely accurate. While most people picture Megalodon as a sized up Great White, nobody truly knows its proper body shape and proportions, let alone its appearance. Even the true lineage of Megalodon is a massive question amongst paleontologists; after all, Megalodon is its species name, not genus name. There has been some debate as to whether Megalodon belongs to the Carcharodon genus, making it related to the Great White, or rather the Carcharocles or Otodus genus. At the moment, Carcharocles Megalodon is the prevailing name and the Mako shark is believed to be its closest living ancestor. With such questions as appearance, size and family history up in the air, Megalodon currently holds the title as the least-understood famous animal of all time. 

Don’t Forget it’s Extinct!

Thanks to the Discovery Channel (which isn’t particularly good as a scientific network) and Jason Statham, a lot of people think Megalodon may still be out there. Sigh… Its dead. Dead and extinct. As dead and extinct as any other dead and extinct animal.

When Megalodon went extinct some 3.6 million years ago, the seas it inhabited were undergoing drastic changes. First, cooling global temperatures made life difficult for Megalodon, as they were adapted to warmer temperatures and thus were forced to live closer to the equator. Second, a significant decrease in whale species at the end of the Miocene made food scarcer for Megalodon. Their primary prey source was simply not as abundant as it had been in the past. Lastly, the formation of a land bridge between North and South America significantly altered the flow of nutrients between the Atlantic and Pacific oceans. This event caused a further drop of diversity in the marine environments that Megalodon called home, significantly reducing the amount of possible prey for Megalodon. The combination of these events, plus the evolution of smaller but more portable and advanced predators such as killer whales and great white sharks, forced Megalodon into extinction. With Megalodon extinct for good, trips to the beach are just slightly more relaxing.

References:

The artwork found in this article is credited to:

Megalodon attacking a pod of whales’ courtesy of Jaime Chirinos, whose artwork can be found at his website here

Megalodon next to a diver courtesy of Sharkopedia, found here

Great white tooth next to a Megalodon tooth found here

Livyatan vs Megalodon made by an unknown artist, found here

The jaws of Megalodon found here

Frankie Schembri et al, Aug. 9, 2018. “Could the Star of The Meg Really Bite a Ship in Half? We Took a Paleobiologist to the New Movie to Find Out.” Science, 9 Aug. 2018, www.sciencemag.org/news/2018/08/could-meg-really-bite-ship-half-we-took-paleobiologist-new-movie-find-out.

“Great White Shark.” National Geographic, 21 Sept. 2018, www.nationalgeographic.com/animals/fish/g/great-white-shark/.

Hall, Danielle. “The Megalodon.” Smithsonian Ocean, 24 May 2019, ocean.si.edu/ocean-life/sharks-rays/megalodon.

Life through the Ages II: Twenty-First Century Visions of Prehistory, by Mark P. Witton and Charles Robert Knight, Indiana University Press, 2020, pp. 120-121.

Prothero, Donald R. The Story of Life in 25 Fossils: Tales of Intrepid Fossil Hunters and the Wonders of Evolution. Columbia  University Press, 2018.

“Whale Shark.” National Geographic, 21 Sept. 2018, www.nationalgeographic.com/animals/fish/w/whale-shark/.