Megalodon Might Not Have Looked Like a Great White Shark on Steroids

The megalodon—the biggest shark to have ever lived—may not looked like an overgrown great white shark, as it is often portrayed, scientists have said.

In a study published in the journal Historical Biology on February 6, scientists from the Department of Biological Sciences at DePaul University in Chicago said that there was no evidence to support or refute any assertions regarding the appearance of Otodus megalodon.

Commonly known as the megalodon, this species of shark first appeared on Earth around 20 million years ago before going extinct an estimated 3.6 million years ago. It is thought they could grow to around 60 feet in length.

A number of factors are believed to have led to the disappearance of the megalodon. These include being outcompeted for prey by great white sharks, changes to sea levels and the reduction of coastal habitats.

Typical depictions and assumptions about what the shark looked like were based on fossils of megalodon teeth and vertebrae, and the shape of existing sharks like modern great white sharks, which lived alongside megalodons, before the larger animals became extinct.

Modern references to the megalodon such as those found in the 2018 action movie The Meg show the animal looking like a giant version of contemporary great white sharks.

The paper's authors said those assumptions lacked evidence. Examining two-dimensional charting of the evolution of shark bodies, the authors strongly suggested that there was no relationship between the the charts used in previous studies and the projected shape of the megalodon.

"Although it is still possible that O. megalodon could have resembled the modern great white shark or lamnids, our results suggest that the two-dimensional approach does not necessarily decisively allow the body form reconstruction for O. megalodon," Jake J. Wood, one of the study authors, said in a statement.

The paper directly challenged the assumptions made in a separate study published in 2020, which inferred the shape of a megalodon based on five living species of sharks—including great white sharks.

That study, the scientists said, included a dubious application of a bracketing technique that charted the evolutionary history of sharks to infer what megalodons looked like.

"All previously proposed body forms of Otodus megalodon should be regarded as speculations from the scientific standpoint," Phillip C. Sternes, another co-author of the research, said in a statement.

"Any meaningful discussion about the body form of O. megalodon would require the discovery of at least one complete, or nearly complete, skeleton of the species in the fossil record," Wood said.

Kenshu Shimada holds a megalodon tooth
Paleobiologist Kenshu Shimada holds a megalodon tooth. Shimada was one of a team of scientists who said that previous research that suggested what megalodons looked like were not based on sufficient evidence. JEFF CARRION/DEPAUL UNIVERSITY