The megalodon, a prehistoric hunter which has for years carved an imagined silhouette similar to that of an enormous great white shark, could have been longer, sleeker, and altogether more superior than we’ve all been led to believe.

These are the conclusions drawn by researchers from the University of California, Riverside who – following an examination of the megalodon’s vertebral column – now conclude that the prehistoric predator was actually closer in shape to the lemon shark or even a large whale.

Just supersized.

Findings published this week in the journal Palaeontologia Electronica suggest the prehistoric marine predator is likely to have reached lengths of up to 80 feet – about two school buses – and weighed in at an estimated 94 tonnes, making it comparable to the size of a large blue whale.

Until now, conclusions over the shape and size of the megalodon had been drawn through the examination of its tooth size, a more traditional method for gauging body-length estimates of sharks in general. Researchers from the University of California, Riverside argue that this new, novel approach however, offers the “most robust analysis:” to date.

Phillip Sternes, a shark biologist who completed his Ph.D at the University, said: “Rather than resembling an oversized great white shark, it was actually more like an enormous lemon shark, with a more slender, elongated body. That shape makes a lot more sense for moving efficiently through water.”

This is because great white sharks have a stocky, torpedo shaped body built for bursts of speed, with a broad midsection that tapers sharply towards the tail. In contrast, lemon sharks have a leaner, more uniform body shape, with a less pronounced taper.

This longer, more cylindrical build allows for smoother, more energy-efficient swimming. As the study suggests, if megalodon had a body structure more akin to a lemon shark, it would have looked much sleeker than the bulky kind of predator often depicted in film and television.

It all comes down to efficiency in the water.

“You lead with your head when you swim because it’s more efficient than leading with your stomach,” said Tim Higham, University of California, Riverside biologist who contributed insights to the study. “Similarly, evolution moves toward efficiency much of the time.”

The study highlights how large aquatic animals including sharks, whales, or even extinct marine reptiles follow similar patterns when it comes to body proportions.

“The physics of swimming limit how stocky or stretched out a massive predator can be,” said Higham. 

While debates have raged over whether the megalodon was a high-speed predator or a slower, cruising hunter, the new study suggests it was actually a balance of the two, hinting that the shark likely swam at moderate speeds, with the ability to burst forward when attacking prey.

As a newborn, the study has indicated, a megalodon would already have been nearly 13 feet long – roughly the size of an adult great white shark – making it “entirely possible” that megalodon pups were already taking down marine mammals “shortly after being born”.

The breakthrough moment of this study was identifying the lemon shark as the ‘best living analog’ for megalodon’s proportions. Unlike the great white, the lemon shark has a more elongated body – proportions found to be a ‘near perfect match’ when scaled up to the megalodon’s estimated length.

“This research not only refines our understanding of what megalodon looked like, but it also provides a framework for studying how size influences movement in marine animals,” said Sternes. “Gigantism isn’t just about getting bigger – it’s about evolving the right body to survive at that scale. And megalodon may have been one of the most extreme examples of that.”

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