A new study has now found that newborn Megalodon sharks were supersized fish that were larger than most adult humans. As per a study conducted by paleobiologist Kenshu Shimada of DePaul University in Chicago along with his colleagues, the body size of the iconic gigantic Megalodon or megatooth shark, about 50 feet in length, was much larger compared to body sizes of its relatives. As per a statement by DePaul University, while the Otodus megalodon is portrayed as a super-sized monstrosity in films like the 2018 The Meg, the maximum possible body size for the species is about 50 feet at present, or 15 meters; not 16 meters or larger, as indicated by earlier studies.
The fish belong to a shark group called lamniforms, which have a rich fossil record. Yet, the species is poorly understood because these cartilaginous fishes are mostly identified by their teeth. The recent study used measurements from specimens of all the thirteen species of present-day macrophagous lamniforms to make an estimation of the body, jaw and tooth lengths of their extinct ancestors.
The researchers made use of an imaging technique called micro-computed tomography to study three well-preserved vertebrae from one shark. The images revealed 46 growth bands, suggesting that the shark lived to the ripe old age of 46. The creature is estimated to be about 9 metres long at death, hinting that the animal grew at a rate of about 16 centimetres each year.
This shows that the shark would have been about 2 metres long at birth, which is large enough for a newborn to be a fierce predator of the seas, and not need to compete for food. By combining the growth trajectory findings with data about body size in the largest-known individuals, the researchers estimated that Megalodon sharks may have lived to be at least 88 to 100 years old, according to a LiveScience report. But this inferred estimate is "rather theoretical" and in need of further investigation, the researchers said.
source https://www.firstpost.com/tech/science/megalodon-shark-fossils-suggest-that-newborns-were-larger-than-adult-humans-study-9200801.html