The biggest shark found thus far — the monstrous Otodus megalodon — might have been a smooth, long-bodied leviathan.
A recent take a look at the extinct predator’s fossilized stays suggests its physique was many meters longer and presumably extra slender than earlier reconstructions, researchers report January 22 in Palaeontologia Electronica. The findings might provide higher insights into the biology and life-style of megalodon, together with how briskly it swam or what it ate (SN: 6/27/23).
Reconstructing what historic, extinct animals appeared like after they had been alive is difficult, even when full fossilized stays can be found. However reconstructing megalodon is far tougher. Like all sharks, the large had a cartilaginous skeleton that preserves poorly relative to bone. It’s principally identified from enamel and lots of meters of fossilized, cartilaginous vertebrae, with the remainder of the skeleton remaining a thriller.
Historically, fashionable nice white sharks (Carcharodon carcharias) have been used as a mannequin for megalodon’s physique form. That’s as a result of nice whites are the biggest predatory sharks alive at the moment and nice whites and megalodons are categorized in considerably carefully associated households.
A 2022 reconstruction that extrapolated from nice whites caught the eye of Kenshu Shimada, a paleobiologist at DePaul College in Chicago, and his colleagues. That research primarily based its reconstruction on the cartilaginous vertebral column of purported megalodon stays housed in a Belgian museum. Including collectively all of the vertebrae end-to-end revealed a physique size of over 11 meters. However Shimada and his colleagues observed that older work on that very same specimen from the Nineties had calculated your complete animal’s size as about 9 meters. That work was primarily based on the diameters of the vertebrae and the way these scale with measurement in nice white sharks, which tops out at round 6 meters lengthy. However the 2022 research nonetheless assumed megalodon was roughly nice white-shaped, Shimada and his colleagues argue.
Of their reassessment of the Belgian megalodon specimen’s vertebral column and the 2022 reconstruction, Shimada and his group query counting on the form of nice white sharks to construct our view of megalodon. Megalodon’s vertebral column is comparatively skinny in contrast with the sturdier vertebrae that help the beefy brawn of nice whites, makos and different fashionable relations, the group notes. The researchers provide a brand new interpretation: As a result of such a small vertebral column would make extra sense in an extended, leaner physique form, megalodon might have been constructed extra like a bus than a van. General, it could have been an excellent greater predator than researchers thought, Shimada says.
This research was “a significant studying second for each myself and lots of different scientists in that we have to take a broader perspective when reconstructing extinct animals, particularly megalodon,” says coauthor Phillip Sternes, an organismal biologist on the College of California, Riverside.
A slender physique might imply that megalodon wasn’t as highly effective a swimmer as nice whites are. This matches latest analysis from Shimada and his colleagues on the form of a megalodon scale that prompt the shark was a gradual cruiser able to quick bursts of pace. This shift in physique form might trace at the way it ate or how a lot it ate, says paleontologist Dana Ehret of the New Jersey State Museum in Trenton, who was not concerned in both work.
“When working with extinct species, particularly ones that don’t have any shut dwelling relations at the moment, we do our greatest by estimating what they could have appeared like or how they behaved however it’s by no means precise,” he says.
The brand new research takes an attention-grabbing method, says vertebrate paleontologist Michael Gottfried, however the researchers nonetheless depend on nice white sharks as a mannequin in some methods, like on patterns of the scale of vertebrae in several components of the shark’s physique. Gottfried and his colleagues had been the researchers who measured and reconstructed the Belgian specimen as roughly 9 meters lengthy within the Nineties. He says he isn’t positive how precisely the vertebrae might be added as much as a complete size, as a result of most of the vertebrae are incomplete or fragmentary.
“In the end, we’re nonetheless speculating on physique kind and lots of different facets of megalodon,” says Gottfried, of Michigan State College in East Lansing. Extra fossil materials from the pinnacle and fins could be essential for understanding how the large shark appeared.
