Largest shark ever lived was not as bulky as we thought—scientists uncover shocking details

For years, scientists assumed that the massive megalodon resembled an oversized great white shark. But what if that assumption was wrong?
Kenshu Shimada, a paleobiology professor at DePaul University, and his colleagues started questioning this idea a few years ago. Their doubts grew after reviewing a 2022 study that used a 3D model to estimate the megalodon’s size. Shimada noticed that some of the math behind the shark’s proportions didn’t quite add up.
That’s when the lightbulb moment hit. “We kind of realized—click—that the great white shark is not a good model,” Shimada explained.

To find a more accurate comparison, Shimada’s team analyzed 145 living shark species and 20 extinct ones, carefully measuring the proportions of their heads, bodies, and tails. By comparing these to the fossilized remains of megalodon’s vertebral column, they could estimate the full body shape of this ancient predator.
The results were surprising. Instead of the bulky, muscular build of a great white, the megalodon likely had a longer, more streamlined body—closer in shape to a lemon shark. This discovery has the potential of changing our understanding of megalodon.
Shimada’s findings align with a fundamental rule in marine biology: thinner bodies allow animals to grow larger while still moving efficiently. Great white sharks, which max out at around 20 feet (6 meters), may be as big as a stocky shark can get without sacrificing speed. Meanwhile, sleeker animals like blue whales, which can grow up to 100 feet (30 meters), can reach incredible sizes without losing agility.
“If you stay in a skinnier body, there is a better chance of being able to grow larger,” Shimada said. And based on his team’s calculations, megalodon may have been as long as 80 feet (24 meters)—much bigger than previously believed.

Experts have expressed surprise at both the new size estimate and the idea that megalodon looked more like a lemon shark than a great white. But the real test will come if and when scientists uncover a complete megalodon skeleton.
“What we really need is the discovery of the complete skeleton,” Shimada emphasized. “That will support or refute whether it was really skinny or stocky.”
Until then, the mystery of megalodon continues—but thanks to this research, we’re closer than ever to understanding the true form of the ocean’s most legendary predator.