Ancient Giant Shark Had Strongest Bite Ever, Model Says

Ker Than
for National Geographic News
August 5, 2008
Prehistoric megalodon—literally "megatooth"—sharks had the most powerful bite of any creature that has ever lived, according to a new model.

Its bite was strong enough to crush an automobile and far exceeded that of the great white shark and even Tyrannosaurus rex.

Known mostly from the large teeth it left behind, Carcharodon megalodon first appeared in Earth's seas about 16 million years ago (in the Neogene period) and dined on giant prehistoric turtles and whales.

"Megalodon's killing strategy was to bite the tails and flippers off large whales, effectively taking out their propulsion systems," said study leader Stephen Wroe of the University of New South Wales in Australia.

The prehistoric shark may have grown to lengths of over 50 feet (16 meters) and weighed up to 30 times more than the largest great white.

"A great white is about the size of the clasper, or penis, of a male megalodon," said Peter Klimley a shark expert at the University of California at Davis, who was not involved with the current research.

"Could Have Crushed a Small Car"

Wroe and his colleagues extrapolated the bite force of megalodon from data they collected from great whites.

The team created a computer model of a great white's skull, jaw, and head muscles from images generated by a computerized tomography (CT) scanner.

They then ran "crash test" simulations with the model to reveal the stresses and strains it could withstand and the strength of its bite.

The team estimated a great white could generate a maximum bite force of about 4,000 pounds (1,800 kilograms).

Because megalodon was much bigger than a great white, it might have chomped down on prey with a force of between 24,000 to 40,000 pounds (10,900 to 18,100 kilograms), the researchers say.

"At [40,000 pounds], I reckon it could have crushed a small car," Wroe told National Geographic News.

"Of course it would probably have broken most of its teeth in the exercise."

For comparison, T. rex, one of the largest land carnivores of all time, had a bite force that has been estimated at only 6,834 pounds (3,100 kilograms).

The work will be detailed in an upcoming issue of the Journal of Zoology.

Jaw Structure

Most of what is known about megalodon comes from the study of its teeth, which have features that suggest they were arranged in a broad mouth. And animals with broad mouths typically have short snouts.

Animals with short snouts, furthermore, generally have more leverage when they bite and generate more force in the up-and-down direction, scientists say.

Klimley, of the University of California, said megalodon's powerful bite is consistent with the theory that the ancient shark had a pug nose.

Chuck Ciampaglio, a paleontologist at Wright State University in Ohio, is more skeptical.

Megalodon was likely not a direct ancestor of great whites, Ciampaglio said, so it "may have quite a different skull and jaw structure."

Also, megalodon may have used fewer muscles to power its bite than the model predicts.

"As an animal becomes larger, much more of the animal's weight is consumed by support structures, not muscles," Ciampaglio said.

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