DeAgostini/Getty Images
Previous reconstructions of megalodon, such as this one, were based on the proportions of modern great white sharks.
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megalodonHuge prehistoric shark People depicted in films such as The Meg are said to have thinner bodies than previously thought. new research.
Many mysteries remain about megalodon’s ecology, but until now the great white shark has been used as a model for its appearance. But a new study by a team led by paleontologist Kenshu Shimada of DePaul University in Chicago and doctoral candidate Philip Stearns of the University of California, Riverside suggests that megalodon’s body would have been leaner than a great white shark. are doing.
Otodus megalodon lived more than 23 million years ago. Fossils of extinct giants are difficult to obtain. Although there are many fossil shark teeth, their bodies are mainly composed of cartilage rather than bone, and they are rarely preserved.
Takehide Shimada/DePaul University
The figures show previous and new schematic interpretations of the body morphology of Otodus megalodon. The dark gray silhouette represents a previously reconstructed body shape based on a great white shark. The light gray outline indicates a newly interpreted, more elongated body shape.
The new study is based on a re-evaluation of an incomplete set of fossil vertebrae discovered in Belgium.
Previous studies have estimated that the megalodon was 9.2 meters (30.2 feet) long, but Shimada and his co-authors say it was actually at least 11.1 meters (36.4 feet) long. There is.
Shimada told CNN that if the shark had the same body size as a great white, the fossil vertebrae would not have been strong enough to support a shark of this length.
“If the great white shark’s body shape applied directly to the spinal column, the diameter of the vertebrae that the shark could support would be unrealistically small,” he says.
Shimada explained that a spinal column of this diameter would not be able to adequately support the muscles of a body like a great white shark, increasing the risk of spinal cord injury.
“This is especially important given that sharks’ skeletons are cartilaginous (made of cartilage) and therefore not as strong as bone,” he added.
But he also noted that in some shark species, including megalodon, this cartilage can undergo some degree of strengthening through calcification, or accumulation of calcium, and then harden.
“The new study takes into account spine and body size ratios in a more biologically realistic way, and may show that the body is leaner, at least compared to modern great white sharks.” he said.
The study suggests that “extant great white sharks do not necessarily serve as good modern analogues, at least in assessing certain aspects” of megalodon biology, Shimada said. Ta.
He said, “There are still many misunderstandings and unanswered questions about megalodon’s ecology, and I would like to scientifically correct and clarify them based on the fossil record.”
Currently, the fossil record of megalodon is only partial, and Shimada hopes that one day a complete skeleton will be discovered.
The study was published Sunday in the paleontology journal Palaeontologia Electronica.
A previous study published in August 2022 found that megalodons can prey on prey as large as orca whales (which can be up to 26 feet long and weigh more than 8,000 pounds) with just five bites. It is estimated that it was possible.
According to the British Natural History Museum, megalodons went extinct about 3.6 million years ago, but scientists are still trying to figure out why.
One theory is that their deaths had something to do with the fact that they were warm-blooded.
Previous research by Shimada et al. has shown that being warm-blooded may be one of the main factors promoting Megalodon’s large size and overall ability as a predator; They conclude that this may also be the cause of their increased sensitivity to environmental changes.
“The fact that megalodon disappeared suggests the vulnerability of warm-blooded animals, as they require constant food intake to maintain a high metabolism,” Shimada told CNN last July. Told.
“Perhaps the cooling of the climate caused changes in the marine ecosystem, lowering sea levels and changing the habitat of populations of the types of marine mammals and other species that megalodon prey on, leading to their extinction.”