Study author Kensho Shimada, a professor of paleontology at DePaul University in Chicago, said the megalodons, known scientifically as Otodus megalodon, were massive sharks that grew up to 50 feet long and roamed the oceans 15 million to 3.6 million years ago.
Jack Cooper, a fossil shark researcher and PhD student in the Department of Biological Sciences at the University of Swansea in Wales, UK, who was not involved in the study, said the 6.6-foot measurement is fairly accurate and is consistent with other findings in Megalodon nurseries in Panama and Spain. a study.
He said the study is important because there is not much research on megalodon reproduction.
To find out the animal’s height at birth, researchers looked at CT scans of megalodon vertebrae that were originally found in Belgium in the 1860s. Much like tree rings, megalodon vertebrae have annual growth ranges that allow scientists to track the age of the shark.
The specimen was thought to be 46 years old when it died, so Shimada counted the growth bands up to the birth ring and counted the animal’s height at birth. This particular shark is estimated to be around 30 feet long at death.
Survival of the fittest
These extinct marine creatures did not grow this large in the womb due to luck.
While growing inside her mother, megalodon was eating another unpeeled egg, which is known as intrauterine cannibalism.
“The result of egg-eating behavior is that only a few puppies will survive and develop, but each of them can become quite large at birth,” Shimada said.
Their large size at birth reduces the chances of young megalodons being eaten by other predators.
Some modern sharks that are part of the order Lamniformes – the same species to which megalodons belong – also exhibit this behavior.
Sand tiger sharks eat unpeeled eggs in the womb, and Shimada said they sometimes eat other siblings that have hatched.
He says that raising sand tiger sharks costs a female tiger shark a lot of energy, but like megalodons, this evolutionary strategy reduces the chances of eating them after birth.
Shimada, who wants to discover more, said there was still a lot unknown about the giant shark. He had an interest in megalodon since he was 13 when he found a 2-inch tooth megalodon in a geological site outside Tokyo.
While this study revealed a lot about the birth of a megalodon, the specimen was only 46 years old, which is the average age for this animal.
Shimada hopes to research the last years of the shark, which are estimated to be between 88 and 100 years old, to find out their growth pattern.