New study suggests megalodons may have grown 15 feet longer than some previous estimates, had enormous babies, and didn’t look like supersized great white sharks.
Megalodons May Have Been Larger and More Slender Than We Thought, Study Suggests
Megalodons might have grown up to 80 feet (24.3 meters) long — about 15 feet (4.5 m) longer than previous estimates — according to a new study. Researchers also suggest these ancient sharks were more slender and streamlined than once believed.
“Earlier predictions based on teeth put megalodons at around 18-20 meters (59-65 feet),” said study co-author Phillip Sternes, an educator at SeaWorld San Diego, in an email to Live Science.
Megalodon (Otodus megalodon), which ruled the oceans between 20 million and 3.6 million years ago, is mostly known from fossils of teeth, vertebrae, and scales. The largest known megalodon fossil — a 36-foot (11 m) section of its spine — offers crucial clues about its size.
In a study published March 9 in Palaeontologia Electronica, researchers analyzed megalodon fossils and compared them to over 150 species of living and extinct sharks. Based on proportions and extrapolating from the 36-foot spine section, they estimated that this individual may have had a 6-foot (1.8 m) head and a 12-foot (3.6 m) tail, totaling about 54 feet (16.4 m) in length.
However, since the largest megalodon vertebra ever found measures 9 inches (23 cm) in diameter — significantly larger than those from the 54-foot individual — scientists believe megalodons could have reached up to 80 feet (24.3 m).
The study also suggests megalodons may have given birth to live young measuring 12 to 13 feet (3.6 to 3.9 m).
Rethinking Megalodon’s Shape
Though megalodon teeth resemble those of great white sharks, leading many to assume a similar appearance, this new research proposes that megalodons were more slender and hydrodynamic — perhaps shaped more like lemon sharks than great whites.
“Past studies assumed megalodon looked like a massive great white without clear evidence,” said lead author Kenshu Shimada, paleobiology professor at DePaul University in Chicago.
Using hydrodynamic models based on large marine animals like whale sharks and basking sharks, the team concluded megalodon was likely built for efficient swimming, with a streamlined body.
Still, not everyone agrees. Jack Cooper, a megalodon researcher at Swansea University (UK), cautioned that these conclusions are speculative. “The hydrodynamic models are largely based on whales, which move differently than sharks,” Cooper noted. “While the proposed body plan is possible, it remains a hypothesis, and previous reconstructions can’t yet be dismissed.”
Until more complete fossils are found, the true size and shape of megalodon will remain an open question — but this new study adds fascinating possibilities to the debate.