|Name Meaning||Giant tooth||Height||N/A|
|Pronunciation||MEG-uh-loh-don||Length||4.2–20.3 meters (47–67 feet)|
|Era||Cenozoic – Neogene Period||Weight||65 metric tons (about 143,000 pounds)|
|Classification||Chondrichthyes, Lamniformes, & Otodontidae||Location||Fossils are found in various locations worldwide|
Sharks are the apex predator of today’s marine ecosystem.
Their presence in the world’s oceans today makes venturing too deep beyond the shores an adventure only for the strong-willed.
But several million years ago, the world’s oceans were home to a bigger and even more voracious version of present-day sharks.
3.6 million years ago, the biggest danger lurking in the deep was the 60-foot-long megalodon.
Also commonly referred to as meg, megalodon wasn’t just the largest shark or fish that has ever lived; it also holds the record for the largest predator in Earth’s history based on its weight.
The meg was the top predator in Earth’s waters from the Early Miocene to the Pliocene epochs (between 23 and 3.6 million years ago).
While everyone agrees that the megalodon was one of the most powerful predators that have ever lived, estimating the true size of this giant shark has been a little difficult.
Like modern sharks, the megalodon’s skeleton was formed by cartilage instead of bones, which is hardly preserved in the fossil record.
Megalodon is mostly preserved in the form of gigantic triangular fossil teeth, which is the hardest part of their skeleton.
These teeth and jaw bones give us an idea of the shark’s scale but provide limited information about its appearance and maximum size.
The name megalodon translates as big tooth, a reference to the massive tooth fossils.
Interestingly, this ancient shark’s popular name is its specific name.
The genus name Otodus is not as well-known to the general public.
In this article, we’ll discuss some of the things we do know about the megalodon, its appearance, and how it lived.
Due to limited fossil evidence, details of the true size, appearance, and physical characteristics of the world’s biggest shark species are still quite controversial.
The megalodon is classified as a mackerel shark, suggesting that the shark’s shape and general form would have been similar to that of typical sharks we’re familiar with today.
In terms of its physical appearance, the megalodon has been compared to different shark species, including the great white shark, the basking shark, the whale shark, and the sand tiger shark.
Scientists still differ on whether or not it indeed resembles any of these sharks.
The meg had a streamlined and elongated body tapering towards the tail and was equipped with powerful fins to propel it through the water.
The megalodon’s jaws may have been blunter and wider compared to that of the great white.
But the fins were probably similar in shape.
If the megalodon was more similar to the basking shark or whale shark, it means it would have had a crescent-shaped tail fin paired with a small anal and a second dorsal fin.
The two sides of the shark’s tail fin would have had a caudal keel too.
The most controversial aspect of the megalodon’s appearance is its size.
Because it is only known from fragmentary jaw bones and tooth fossils, estimates of the megalodon’s true size remain contradictory.
The maximum total length estimated so far ranges between 4.2 and 20.3 meters (47–67 feet).
But the average length for most individuals has been found to be around 10.5 meters (34 feet).
Based on these estimates, the megalodon would have been about the same size or slightly bigger than the whale shark, which is the longest shark today at about 18.8 meters (62 feet) for the biggest individual.
But the megalodon was unrivaled in the weight category.
A 17-meter (56-foot) megalodon would have weighed about 59 tons, more than twice the size of the biggest whale shark today.
And the biggest individuals could have easily maxed out at about 114 tons.
Not only was the meg the biggest shark to have ever lived, but it also exceeded any of the biggest predators to have ever walked the planet or inhabited Earth’s prehistoric seas.
Various reasons have been proposed to explain why the megalodon grew to such a large size.
Climatic factors and the abundance of large prey animals to feed on may have influenced the evolution of this shark.
The megalodon had to grow larger to keep up with the large size of the prey species in its ecosystem.
Habitat and Distribution
Megalodon had a wide geographic range during its existence.
It is believed to have had a cosmopolitan distribution meaning it inhabited oceans all around the world.
Fossils of the megalodon have been recovered from every continent except Antarctica, which further supports the theory that it had a global distribution.
However, it is more commonly found in tropical and subtropical climates.
Note that this does not necessarily mean the shark was more abundant in this region.
The abundance of megalodon fossils in these areas can be attributed to better preservation conditions in these regions due to various geological factors.
Scientists have been able to determine the likely conditions of this shark’s habitat through carbonated bioapatite studies of its tooth fossils.
Based on this, it has been determined that the megalodon lived in waters within a temperature range of about 1–24 °C (34–75 °F).
It exhibited mesothermy, which is the ability to keep its body temperature higher than its surroundings by conserving metabolic heat.
Because of this, the megalodon would have been able to endure and survive in low-temperature conditions.
Megalodon was an adaptable predator that thrived in a wide range of habitats.
This includes shallow coastal environments, swampy lagoons, continental shelves, and deep offshore areas.
The megalodon’s immense size and powerful swimming abilities allowed it to roam freely and explore vast expanses of the ocean in search of food.
Fossils of the megalodon discovered so far show that the average body size of this shark varied from one region to the other.
Their size may have also varied based on the specific ocean where they lived.
Generally, specimens discovered in the Southern Hemisphere tend to be larger on average compared to those found in the Northern Hemisphere.
The average length of megalodon specimens discovered in the Northern Hemisphere is about 9.6 meters (31 feet), while those from the Southern Hemisphere were about 11.6 meters (38 feet long).
A similar variation is seen for individuals that lived in the Pacific and Atlantic oceans.
The Pacific megalodons were bigger, with an average length of about 10.9 meters (36 feet) compared to 9.5 meters (31 feet) for the Atlantic megs.
Megalodon lived during the Cenozoic Era, from the Early Miocene to the Pliocene epochs.
This was approximately 23 to 3.6 million years ago.
The climate during this time was generally warmer than it is today, with fluctuating temperatures from time to time.
During the Early Miocene, the Earth experienced a relatively warm climate, but it gradually cooled during the Late Miocene and into the Pliocene.
These temperature changes likely influenced the distribution and abundance of various marine species, including the megalodon and the animals it preyed on.
The changing climate may have also contributed to the megalodon’s eventual extinction.
The arrangement of continents and ocean currents also changed significantly during the Cenozoic.
This would have also influenced the distribution of marine life during this period.
For instance, the opening and closing of oceanic gateways, such as the connection between the Atlantic and Pacific Oceans on land, while facilitating the distribution of marine ecosystems.
Towards the end of the Pliocene Epoch, the megalodon faced challenges as the Earth’s climate continued to cool.
While the cooling trend did not affect the megalodon directly due to its ability to regulate its internal temperature, it did lead to the decline of some of its primary prey species.
This, combined with other ecological factors, likely contributed to the eventual extinction of the megalodon.
Behavior and Diet
megalodon was a highly specialized and efficient predator whose behaviors may have been similar to that of its living relatives today.
This shark had a streamlined body with a large and muscular tail, suggesting that it was an active swimmer capable of cruising through the water with great speed and agility.
As with most modern sharks, megalodon likely used its pectoral fins for stability and control while swimming.
Scientists have been able to estimate a likely top speed for this shark based on its proposed body proportions and comparison to other living shark species.
A cruising speed of about five kilometers per hour (3.1 miles per hour) has been proposed for the megalodon.
This is equivalent to a mean speed of about 0.09 body lengths per second for a 16 meters (52 feet) long megalodon.
Based on this estimate, the mean cruising speed of the megalodon would have been faster than that of any living species of mackerel sharks.
It is believed that the megalodon was primarily a solitary hunter.
However, like many shark species today, their populations would have been more concentrated in areas where prey populations were high.
Given its size and predatory nature, it is unlikely that megalodon formed social groups or packs like some modern species of sharks.
Megalodon was an apex predator in its habitats.
Its diet primarily consisted of large marine mammals, such as early whales, dolphins, seals, and other shark species.
Its massive teeth, shaped like broad triangles with serrated edges, were perfectly adapted for grasping and tearing apart large prey.
The megalodon’s jaws were huge, just like the rest of its body.
The jaws of this massive fish could swallow two adult humans standing side by side.
The average size of the jaw has been estimated to be about 2.7 by 3.4 meters.
In addition to being massive, the jaws were lined with up to 276 banana-sized teeth. Each tooth measured about 180 millimeters (7.1 inches) diagonally.
Various studies have been carried out to reconstruct the shark’s bite force and determine just how powerful it was.
Based on these studies, the bite force of the megalodon is about 182,201 Newtons.
That’s more than ten times the bite force of the great white shark.
When hunting for prey, megalodon likely relied on various hunting tactics to capture and kill prey.
Unlike great white sharks that tend to attack prey by targeting the underbelly, megalodon likely attacked large prey from the side, delivering a fatal bite to the heart and lungs area.
The shark’s thick teeth were strong enough to bite through tough skin and bones and could inflict a fatal blow on even the biggest prey.
Fossils of large baleen whales from the Miocene Epoch have been found with huge bite marks on the rib cage like this.
Megalodons probably adapted their attack patterns based on the specific size of the prey they hunted.
For instance, they probably rammed smaller whales with their blunt snout, disorienting them before delivering a fatal bite, while they killed sperm whales with a single bite to the head.
It is also likely that the megalodon immobilized larger prey by biting off parts of their flipper and tails before killing and feeding on them.
Like most modern shark species, megalodon was likely ovoviviparous.
This means they gave birth to live young in the water instead of laying eggs as other fish species do.
Scientists are not entirely sure of the mating behavior of this shark, but it was most likely similar to that of present-day sharks.
Males probably had claspers which were effective for latching on to the females during copulation.
After mating, the fertilized eggs develop into embryos inside the female’s body.
Some scientists believe developing megalodon shark babies may have been cannibalistic.
Given their size, each embryo would have needed significant space and resources to thrive, and cannibalizing other embryos would have given them more room to grow.
The female would then give birth to fully formed pups in the water.
Megalodon pups were most likely born in shallow nursery areas instead of the open seas.
They were up to two meters (6.6 feet) long at birth.
Although they were quite large compared to many other shark species and capable of hunting prey right away, they were still at risk of predation from larger predators in their ecosystems.
The juveniles likely had a very slow growth rate, similar to many modern large sharks.
The early stages of their life were restricted to the shallow nursery where food was abundant, but the risk of predators was lower.
Their diet at this early stage would have included fish and other small marine animals.
As they grew, young megalodons would gradually venture into deeper waters to prey on larger marine mammals in their ecosystem.
Evolution and History
The first sharks evolved about 450 million years ago, but the Otodontidae family, which includes the megalodon, Megalolamna, and Carcharocles, emerged during the Late Cretaceous Period or the Early Paleocene Epoch.
Their earliest date of evolution has been placed between 66 and 56 million years ago.
The direct ancestors of the mega-toothed shark are early otodontids like the Cretalamna and Otodus.
These are smaller sharks compared to megalodon but are known to exhibit similar tooth shapes and serrations, just like the megalodon.
Over millions of years, the otodontids underwent significant changes and adaptations, especially in terms of their size.
The shift to larger body sizes and the development of more robust teeth were likely responses to the increasing abundance of large marine mammals in their habitats.
The cetaceans (ancestors of whales and dolphins) made the transition from land to water about 50 million years ago and evolved into diverse species with massive sizes.
These new prey species provided plentiful, energy-rich food sources for large predators like the megalodon to feed on.
Some experts also think the megalodon was able to grow so big because it exhibited regional endothermy (or mesothermy).
This means it was intermediate between being cold-blooded and warm-blooded.
This would have led to higher metabolic rates, swimming speed, and bigger sizes.
Another significant evolutionary adaptation observed in the megalodon is the serrations in their teeth.
The megalodon’s teeth are similar to that of the great white shark.
Scientists think this is a case of convergent evolution rather than because the two sharks are closely related.
The increased serrations of the megalodon’s teeth compared to their shark ancestors can be attributed to a change in their predation tactics from tearing and grasping to cutting into flesh.
Interactions With Other Species
Megalodon was an apex predator in its ecosystem.
It was the largest predator and an active swimmer with an impressive dentition adapted to preying on a wide range of animals.
Based on these qualities, Otodus megalodon is often considered one of the most powerful predators to have ever lived.
It preyed on various animals, but the cetaceans (whales and dolphins) formed the bulk of its diet. It also hunted seals, sea turtles, and sirenians in its ecosystem.
Smaller megs, especially juveniles, would have hunted fish, including other sharks.
Evidence for this shark’s voracious habitat is abundant in the fossil records.
This includes numerous bite marks on the fossils of several ancient sharks and cetaceans and the discovery of megalodon teeth in association with whale remains.
Despite their massive size, megalodons would have had to compete with some equally large marine predators.
Some of the marine predators that likely competed with the megalodon include extinct macroraptorial sperm whales like the Livyatan.
Some of these whales grew to a maximum length of about 57 feet and targeted the same prey species as the megalodon.
However, the massive size of the megalodon would have given it an edge over these predators.
Scientists believe the presence of the megalodon in some ancient waters may have caused other shark species to avoid the region.
Megalodon individuals may have also competed against each other.
Like modern sharks, they may have exhibited cannibalism, with larger individuals preying on smaller ones.
As the largest shark ever discovered, the megalodon is one of the most popular prehistoric sharks due to its colossal size and fearsome reputation.
The gigantic triangular teeth of this shark have been found as far back as the 1600s, long before they were conclusively identified as shark fossils.
In Renaissance times, they were identified as the tongue of dragons or ancient snakes.
These notions were corrected by Danish naturalist Nicolas Steno who identified them as shark teeth.
But detailed paleontological studies didn’t begin until the 1800s.
Since then, the megalodon has been a subject of great interest for paleontologists and researchers studying prehistoric marine ecosystems.
Although scientists didn’t have a lot of fossil evidence to go by, numerous tooth fossils and a few vertebrae bones discovered so far have provided valuable insights into the anatomy of this ancient shark and its evolutionary ties to other sharks.
Most of what we currently know about the megalodon’s behavior is based on comparison with other shark species.
The megalodon is most commonly compared to the great white shark.
It was initially classified as a genus of great white sharks before it was recently reclassified into its genus.
Scientists have used their findings about the megalodon to reconstruct ancient marine ecosystems and determine interactions between the large predators and prey of the Miocene and Pliocene periods.
Megalodon is well-known to the general public.
Given its size, movie directors and writers have not passed up the opportunity to include this massive shark as a fictional sea monster.
Some of the most notable instances of megalodon references in pop culture include the 1997 novel by Steve Alten titled “Meg: A Novel of Deep Terror.”
A movie adaptation of this novel was released in 2018.
The megalodon is also commonly featured in books, documentaries, and other scientific materials.
The megalodon is also the stuff of urban legend.
The allure of the megalodon’s enigmatic history has popularized rumors and unlikely sightings that speculate that the massive fish still lives in the depths of the ocean.
While it isn’t uncommon for species that were once thought to be extinct to resurface (like the megamouth shark, which was rediscovered in 1976), the chances of the megalodon shark still living somewhere in today’s cold and nutrient-poor deep sea environment are almost zero.
The megalodon was a species of mackerel shark that lived from the Early Miocene to the Pliocene epoch from 23 to 3.6 million years ago.
As the largest shark species and one the largest predator to have ever lived, the megalodon was an impressive prehistoric animal.
This massive shark preyed on giant prehistoric whales, seals, and dolphins in its ecosystem. It had massive jaws lined with rows of long teeth strong enough to bite through prey.
The megalodon was undoubtedly the top predator in the Miocene and Pliocene environment.
Unfortunately, the shark’s massive size made it difficult to adapt to changes in its ecosystem.
This eventually led to its decline and eventual extinction about 3.6 million years ago.
Despite rumors and speculations, the megalodon is gone forever, replaced by less impressive but equally dangerous predators lurking in the depths of the world’s oceans.
Jerry Young is a self-proclaimed prehistoric animal nerd. He has been fascinated with these ancient creatures for as long as he can remember, and his passion for them continues to this day. With his extensive knowledge and love for prehistoric animals, he is the perfect fit for Gage Beasley Prehistoric.