Here are 15 fascinating facts about the Megalodon Shark, one of the ocean’s most legendary predators.

For over 20 million years, the colossal Megalodon patrolled the seas—and this month, it makes its way to theaters in The Meg. Discover 15 astonishing facts about this fearsome creature.

1. MEGALODON ISN'T THE FULL NAME OF THE SHARK.

While Megalodon is the name widely used in pop culture, documentaries, and low-budget films, it only represents part of the shark’s scientific name. Most researchers place the prehistoric beast within the extinct genus Carcharocles (or occasionally Otodus), while some argue it could belong to the genus Carcharodon (the same genus as the great white shark). Hence, the full scientific name could be Carcharocles megalodon or Carcharodon megalodon. So, megalodon is the species name, not the genus (similar to how Homo and sapiens are distinct parts of our own classification).

There is also a group of fossil bivalves—tiny, hard-shelled mollusks that appeared during the Devonian period and became extinct by the Jurassic period—whose genus name is Megalodon (with a capital M). Don’t expect them to make an appearance in any blockbuster horror movies, though.

2. SOME MEGALODON TEETH COULD GROW UP TO 7 INCHES LONG.

Sharks have skeletons made of cartilage, which doesn’t fossilize well, so our understanding of the Megalodon mostly comes from its teeth. Like modern sharks, the Megalodon constantly shed its teeth, and fossilized specimens have been found on every continent except Antarctica. Studying these teeth has helped scientists conclude that the Megalodon roamed the Earth from 23 to 2.6 million years ago and grew to enormous sizes: The largest megalodon tooth discovered measures 7.5 inches, whereas a great white’s tooth maxes out at around 3 inches.

3. MEGALODON CONTRIBUTED TO THE DEVELOPMENT OF MODERN GEOLOGY.

For centuries, mysterious objects known as glossopetrae, or tongue stones, were unearthed from rocks in Malta. Pliny the Elder believed that glossopetrae fell from the sky during an eclipse, and Medieval folklore claimed they were the result of Saint Paul’s curse on the island’s snakes. Today, it is widely accepted that the largest of these glossopetrae were in fact megalodon teeth.

In 1666, Nicholas Steno, a physician at the Florence court, was given the head of a shark to dissect. He observed the striking similarities between the shark’s teeth and glossopetrae. While others had been working on similar research before him, Steno’s curiosity about how these teeth ended up in the rocks led to broader inquiries in geologic theory, including how rock layers are formed. Today, Steno is celebrated as the “Father of Stratigraphy.”

4. WE'VE DISCOVERED THEIR SPINES ...

Though far rarer than teeth, fossilized megalodon backbones have been found, typically the central part of the vertebra known as the vertebral centra. In the 1860s, a fossilized spinal column with about 150 vertebrae was discovered in Belgium. Other megalodon backbones have been found in Japan and North America as well.

5. ... AND EVEN THEIR FOSSILIZED WASTE.

It seems the giant fish also left behind some petrified waste. In South Carolina, a collection of megalodon teeth was found near what are believed to be coprolites (fossilized shark feces). While the exact origin of the poop is uncertain, it’s likely it came from a megalodon. The largest specimen discovered at the site measured 5.5 inches long and was spiral-shaped. Great white shark poop bears a resemblance, as their intestines are twisted into a corkscrew-like form.

6. IT'S BELIEVED TO BE THE LARGEST SHARK TO HAVE EVER EXISTED ...

Everyone is eager to learn just how large it was, including scientists. However, the truth is we can only make educated guesses for now. A complete megalodon skeleton has never been discovered, and it's unlikely that one will ever be. Estimating the size of an extinct animal based on partial remains like scattered teeth, fragments of spinal columns, and the occasional fossilized poop is no small task.

Ichthyologist John E. Randall once compared the enamel heights of the teeth of both great white sharks and megalodons. He calculated that if the megalodon had similar body proportions to the modern great white, it would have measured around 43 feet in length. Using a different method, biologist Michael Gottfried and colleagues estimated the megalodon’s length at 52 feet, with a weight of up to 48 tons. This conclusion was reached in 1996, six years before scientist Clifford Jeremiah calculated, using the width of megalodon tooth roots, that it could have grown up to 54 feet long. Some other estimates place the shark's length at between 67 and 82 feet.

The largest living species today is the gentle whale shark, which can reach up to 40 feet in length (though reports of larger individuals are often regarded as unverified). Even the smallest estimates suggest that the megalodon was longer and likely much heavier, cementing its status as the largest shark—and most likely the biggest fish—ever to have existed.

7 ... BUT IT WASN'T THE ONLY COLOSSAL SHARK TO ROAM THE SEAS.

When you think of a “prehistoric giant shark,” the first name that probably comes to mind is megalodon—along with no other creature. But while it was the largest, some estimates suggest there may have been anywhere from 10 to 60 “Megatooth” sharks living at the same time [PDF]. For example, Carcharocles chubutensis (also called C. subauriculatus) is thought to have had teeth over 5 inches long, indicating a shark that would have exceeded 20 feet in length. Unfortunately, there’s much debate about which species should be classified as giant sharks, as many of these fossils are incredibly rare [PDF].

8. MEGALODON WAS A WHALE-HUNTER.

This is evident from fossilized whale bones that bear scars matching the size and serrations of megalodon teeth. Just last year, new findings were made. A study published in March 2017 revealed that bite marks from megalodon had been documented on several fossilized bones of filter-feeding whales found in southern Peru, dating back about 7 million years. The paper’s authors noted that the remains included skull fragments from small baleen whales, as well as bones from other whale species and pinnipeds.

One of the whale species targeted by megalodon was Piscobalaena nana, which resembled a mini version of the humpback whale, growing only about 16 feet long. Small baleen whales like Piscobalaena were common in the warm waters where megalodon once thrived. It’s been speculated that megalodon may have specialized in hunting these smaller whales, which could offer an explanation for its eventual extinction. As the planet cooled, tiny filter-feeding whales like Piscobalaena were replaced by massive species such as the modern humpback and blue whales. While these large mammals are adapted to survive in colder waters, it remains uncertain whether megalodon could have done the same. Without its preferred prey and unable to pursue larger cetaceans, the megalodon may have faced its demise. Or, at least, that’s one theory …

9. MEGALODON LIKELY HAD A BITE STRONGER THAN THAT OF T. REX.

Megalodon’s diet wasn’t limited to just whales and pinnipeds; it also consumed fish, turtles, and early relatives of the manatee. To hunt such large prey, megalodon must have boasted an incredibly powerful bite. To gauge the strength of its jaw, a team led by biologist Stephen Wroe CT scanned a 530-pound great white shark [PDF] and used the data to create a digital model of the shark’s head. After running simulations, the researchers determined that a great white can bite with 4000 pounds of force, leading them to estimate that megalodon’s bite force ranged between 24,000 and 40,000 pounds. “At 40,000 pounds of force,” Wroe notes, “it could have crushed a small car.” However, he added, “it would probably have broken most of its teeth in the process.” If this assessment is accurate, megalodon had the most powerful bite of any animal studied to date, surpassing even the Tyrannosaurus rex: A 2017 study concluded that T. rex could only exert 8000 pounds of force when biting into its prey.

10. THE LINK BETWEEN MEGALODON AND THE GREAT WHITE IS STILL UNCLEAR.

C. megalodon and the great white shark (Carcharodon carcharias) shared many similarities. Both targeted large marine mammals, and both had mouths filled with broad, triangular teeth (though megalodon’s teeth were more finely serrated). Because of these similarities, scientists once believed megalodon was a direct ancestor of the great white. However, this theory is no longer widely accepted. A 2005 comparison of hundreds of shark teeth suggested that the great white evolved from an extinct species of mako shark. This theory was further supported in 2012 when paleontologists studied the fossilized jaws of Carcharodon hubbelli, a prehistoric shark from 6.5 million years ago, which showed traits bridging the gap between makos and great whites. Its teeth bore a striking resemblance to those of modern great whites, including the same serrated edges. While the exact relationship between megalodon and great whites remains open for debate, the current consensus is that the latter evolved from a type of mako.

11. A MASSIVE SPERM WHALE MAY HAVE BEEN ONE OF ITS MAIN COMPETITORS.

Livyatan melvillei, a type of sperm whale named after a sea creature from the Old Testament and Moby-Dick author Herman Melville, measured between 45 and 60 feet in length, placing it in the same size range as modern sperm whales. However, unlike their present-day relatives, Livyatan had enormous teeth, with the largest reaching 5 inches in width and 14 inches in length—about the size of a two-liter soda bottle. What prey was this giant whale targeting? Likely, it was feasting on smaller baleen whales, such as the dwarf species we mentioned earlier. First appearing between 12 and 13 million years ago, Livyatan remains have been discovered in the same deposits as megalodon teeth. While scientists continue to study their relationship, it is believed that they likely preyed on similar creatures.

12. YOUNG MEGALODONS SEEMED TO GROW UP IN TROPICAL ‘NURSERIES.’

Modern sharks like great whites and hammerheads, along with several other species, give birth in so-called “nurseries,” which are relatively calm, shallow waters where larger predators are rare. These safe zones offer young sharks a secure environment during their early months or years until they’ve grown large enough to take on the open ocean.

Megalodon offspring may have followed a similar pattern. In Panama, a 10-million-year-old site boasts a remarkably high number of small megalodon teeth, most of which came from juvenile sharks ranging from 7 to 35 feet in length. This has led scientists to believe that the site was once a megalodon nursery. Another potential birthing ground for the species might have been Florida’s Bone Valley region.

13. THOMAS JEFFERSON HAD A MEGALODON TOOTH IN HIS COLLECTION.

Thomas Jefferson, the two-dollar founding father, was a passionate fossil enthusiast. He gathered and wrote about mastodon bones and even the claws of what he mistakenly thought was a giant lion, but which were actually from an ice age ground sloth. Among his collection of prehistoric relics was a megalodon tooth from South Carolina, a specimen that even bears his signature on its enamel. His collection can be found at the Academy of Natural Sciences in Philadelphia.

14. THERE IS NO EVIDENCE TO SUGGEST MEGALODON IS STILL AROUND.

The most recent megalodon fossils date back around 2.6 million years. There are many theories about why this apex predator disappeared after that point. Some suggest that the appearance of new sharks and whales led to megalodon’s downfall, while others have linked its extinction to oceanic cooling. However, the cooling theory has faced recent criticism.

Regardless of what led to the species' extinction, the scientific consensus is clear: megalodon is no longer with us. However, the allure of a good sea monster story persists. Fictional tales, like the Meg series, depict megalodons surviving into modern times, captivating readers. But, as marine biologist Craig McClain and others have pointed out, there’s no solid scientific basis for believing megalodons still lurk in our oceans. McClain argued in Deep Sea News that “if Megalodon existed now, we would not only see [Megalodon] teeth everywhere, as we do with other sharks, but also fossilized ones from the last 2.6 million years. By the way, Megalodon teeth are easily recognizable, not just for their size, compared to other extinct sharks and Great Whites.” In simpler terms, researchers would easily tell megalodon teeth apart from those of living sharks.

It’s also logical to assume that if megalodons were still alive, we'd occasionally find recently-deceased individuals washed up on beaches. Additionally, megalodon teeth would likely be discovered embedded in whale carcasses. Yet, no such evidence has ever surfaced—and the notion of a hidden megalodon population in the deep sea is extremely unlikely. As paleobiologist Meghan Balk explained to The Daily Beast, “Megalodon fossils are typically found in shallower marine deposits. Most large sharks also inhabit the upper 500 meters of the ocean due to the abundance of nutrients. The deep ocean is far too lacking in resources to sustain such a massive predator.”

15. A MEGALODON MOVIE IS COMING SOON.

After spending more than 20 years stuck in development hell, Steve Alten’s iconic shark novel Meg—which spawned a series of books—is finally being adapted into a movie. The Meg, set for release on August 10, stars Jason Statham as a rescue diver sent to save a deep-sea observation team whose underwater station has been damaged after an attack by the thought-to-be-extinct creature.

Additional Sources: Megalodon: Hunting the Hunter; The Story of Life in 25 Fossils: Tales of Intrepid Fossil Hunters and the Wonders of Evolution