15 Toothsome Facts About the Megalodon Shark

For over 20 million years, a gigantic shark popularly known as megalodon stalked the world’s oceans. Here are 15 facts about the toothy predator.

1. Megalodon’s genus name means “ear-shaped tooth.”
2. Some megalodon teeth are over 7 inches long.
3. Megalodon helped invent modern geology.
4. Scientists have discovered a few megalodon vertebrae ...
5. ... and corkscrew-shaped poop.
6. Megalodon was probably the largest shark that ever lived.
7. It wasn’t the only giant shark in prehistoric seas.
8. Megalodon ate whales.
9. Megalodon probably had a stronger bite than T. rex.
10. It’s closely related to great white sharks.
11. It may have competed for food with an ancestor of sperm whales.
12. Young megalodon sharks grew up in tropical nurseries.
13. Thomas Jefferson owned a megalodon tooth.
14. Megalodon is definitely extinct.
15. It starred in a movie with Jason Statham.

Megalodon’s genus name means “ear-shaped tooth.”

Most taxonomists classify megalodon in the genus Otodus (replacing its earlier classification in the genus Carcharocles) along with a few other species of large, extinct sharks. Its scientific name is Otodon megalodon. Don’t confuse the big-toothed predators with the small fossil bivalves in the genus Megalodon, though.

Some megalodon teeth are over 7 inches long.

Fossilized megalodon teeth have been found on every continent except Antarctica. Analysis of the teeth allowed scientists to determine that the species lived from 23 to 2.6 million years ago and was truly massive: The biggest megalodon tooth on record is 7.5 inches long. A great white shark’s teeth reach a maximum length of about 3 inches.

Megalodon helped invent modern geology.

People had dug megalodon teeth out of rocks in Malta for centuries, though no one knew exactly what they were. They became known as glossopetrae, or tongue stones. Pliny the Elder thought glossopetrae fell from the heavens during an eclipse, and medieval legend attributed them to Saint Paul casting a curse on the island’s serpents.

In 1666, a physician named Nicholas Steno received a head of a shark to dissect, and he noticed the similarities between the shark’s teeth and glossopetrae. Although others were doing similar work before Steno, he became interested in how the teeth got into the rocks, and that led to investigations of the ways layers of rock form. Today, Steno is referred to as the “father of stratigraphy.”

Scientists have discovered a few megalodon vertebrae ...

Because megalodon skeletons are made of cartilage, which is too soft to form fossils, scientists rarely find remains other than their teeth. A few megalodon backbones have been discovered, though—primarily the central part of the vertebra known as the vertebral centra. In the 1860s, a fossilized spinal column with roughly 150 vertebrae was unearthed in Belgium. Japan and North America have yielded megalodon backbones as well.

... and corkscrew-shaped poop.

Another thing that the giant sharks left behind is petrified poop. At a deposit in South Carolina, hundreds of megalodon teeth were found near coprolites (a.k.a. fossil feces) of a large-bodied shark, thus the maker of this poop was probably a megalodon. The biggest recovered turd at the site was 5.5 inches long and spiral-shaped. Great white shark poop has a similar appearance because their lower intestines are twisted into a corkscrew-like configuration.

Megalodon was probably the largest shark that ever lived.

A complete megalodon skeleton has yet to be found, and it’s doubtful that one will ever turn up. Trying to make an educated guess about an extinct animal’s maximum size on the basis of scattered teeth, disembodied spinal columns, and turds is a challenge.

Ichthyologist John E. Randall once compared the enamel heights of great white shark and megalodon teeth and concluded that if megalodon had the same body proportions as living great whites do, they would be roughly 43 feet long. Using a different formula, biologist Michael Gottfried and colleagues concluded that megalodon reached 52 feet and could have weighed 48 tons. They published their findings in 1996, six years before scientist Clifford Jeremiah used the width of megalodon tooth roots to calculate that a full-grown megalodon could be up to 54 feet long. Other estimates put the shark’s total size in the range of 67 to 82 feet.

The biggest shark species alive today is the whale shark, which can be 40 feet long. Even the smallest estimates suggest that megalodon was longer, and probably a lot heavier, so it's generally considered the largest shark—and most likely the biggest fish—of all time.

It wasn’t the only giant shark in prehistoric seas.

Some scientists estimate that there could have been anywhere from 10 to 60 “megatooth” shark species extant at the same time as megalodon [PDF]. One may have been Carcharocles chubutensis (sometimes called C. subauriculatus), which reportedly had teeth over 5 inches long, meaning the shark would have been well over 20 feet in length.

Megalodon ate whales.

We know this because there are fossilized whale bones covered in scars that perfectly match the size and serrations of megalodon teeth. A 2017 study found megalodon bite marks on several fossilized bones from filter-feeding whales, which were unearthed in southern Peru and are about 7 million years old. “The bitten material includes skull remains referred to small-sized baleen whales” along with fragments of other bones from whales and seals, the authors wrote.

One of the eaten species was Piscobalaena nana, which looked like a miniature humpback; it measured 16 feet long from nose to tail. Small baleen whales like P. nana were common in tropical waters, and megalodon likely specialized in eating this prey, which may have contributed to the sharks’ extinction. As Earth grew cooler, small whales were replaced by bigger whales better adapted to cold seas. Scientists have theorized that megalodon was unable to adapt to climate cooling and the more formidable prey, and eventually died out.

Megalodon probably had a stronger bite than T. rex.

In addition to whales and pinnipeds, megalodon’s diet included fish, turtles, and early relatives of the manatee. To figure out how strong its jaws were, a research group led by biologist Stephen Wroe CT-scanned a 530-pound great white shark and used that data to build a computer model of its head. After running the model through a few simulations, the scientists reported that a live great white can close its jaws with 4000 pounds of force, which led them to estimate megalodon's maximum bite force at 24,000 to 40,000 pounds. That suggests megalodon had the strongest bite of any known organism, including Tyrannosaurus rex, which could chomp with about 8000 pounds of force.

It’s closely related to great white sharks.

Biologists used to think that O. megalodon and great white sharks (Carcharodon carcharias) were close relatives and that megalodon was the great white’s direct ancestor. This is no longer the consensus. A 2005 comparison of several hundred shark teeth argued that the great white must have evolved from a type of extinct mako. Further support for this idea came in 2012, when paleontologists examined a set of fossilized jaws belonging to Carcharodon hubbelli, a prehistoric shark that lived 6.5 million years ago that exhibited intermediate features between broad-toothed makos and great whites. The fish’s teeth looked distinctly great white-esque—right down to the serrations. Although the exact relationship between megalodon and great whites is still up for debate, the prevailing view is that the latter evolved from some type of mako.

It may have competed for food with an ancestor of sperm whales.

Livyatan melvillei is an extinct species of sperm whale named after Moby-Dick author Herman Melville. It grew to 60 feet long, about the same as the living sperm whale (Physeter macrocephalus), but had one notable difference: L. melvillei packed a mouthful of humongous teeth, the largest of which was the size of a 2-liter soda bottle, to consume dwarf baleen whales mentioned earlier. The ancient shark appeared 12 and 13 million years ago and its remains have been found in some of the same deposits as megalodon teeth. Paleontologists are researching the relation between the two, but they likely ate similar prey.

Young megalodon sharks grew up in tropical nurseries.

Great whites, hammerheads, and other modern sharks give birth in safe, shallow water called nurseries where big predators are few and far between. Many young sharks spend their first few months or years in the safety of a nursery until they’ve grown big enough to venture into the open sea.

Megalodon young may have done the same. A 10-million-year-old site in Panama with an unusually high concentration of small megalodon teeth, primarily from adolescent sharks that would have been 7 to 35 feet long, was probably a megalodon nursery. Florida’s Bone Valley region may have served a similar purpose for the species.

Thomas Jefferson owned a megalodon tooth.

The founding father was an avid fossil collector. Thomas Jefferson gathered and wrote about mastodon bones, along with the claws of what he thought was a giant lion but turned out to be an ice age ground sloth. One of the most interesting fossils Jefferson owned was a megalodon tooth from South Carolina, a specimen that bears his signature on the enamel [PDF]. His collection of prehistoric animal remains is now at the Academy of Natural Sciences in Philadelphia.

Megalodon is definitely extinct.

The youngest megalodon remains in the fossil record are around 2.6 million years old. Hypotheses on why the super predator disappeared after that point are numerous and varied, from competition from new sharks and whales to oceanic cooling and diminished prey.

Shark week pseudo-documentaries and shark-related movies keep the dream of megalodon’s survival alive, though. But as marine biologist Craig McClain and many others have noted, there’s no reason to think that megalodon is still lurking in the oceans. “If megalodon existed now, we would not only see [megalodon] teeth all over today, as we do for other sharks, but [we] would have fossilized ones from the last 2.6 million years,” McClain told Deep Sea News.

It starred in a movie with Jason Statham.

After more than 20 years languishing in development hell, Steve Alten’s classic shark novel Meg, which launched a series of books, was finally made into the 2018 undersea thriller The Meg. Jason Statham played a rescue diver tasked with saving the crew of a deep sea observation program whose submarine workstation has been disabled after being attacked by the thought-to-be-extinct megashark. One critic called the flick “enjoyably dumb.”

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A version of this story was published in 2018; it has been updated for 2025.