Were gonna need a bigger shark size estimate. Researchers had based some informed guesses about just how massive the megalodon a prehistoric giant fish that hunted the oceans 13 million years to 15 million years ago was by comparing existing fossils of the extinct species to bones of the present-day great white shark.Formally called Otodus megalodon, the prehistoric predator is known not just for its size but for its distinctive serrated teeth. Because the much smaller modern-day great white shark (Carcharodon carcharias) has similar chompers, Megalodon has often been considered its supersize precursor.However, measuring a creature that inspired The Meg against one that gave creative birth to Jaws may not be apt. If not an apples-to-oranges scenario, it may well be a lemon shark to great white one, according to a paper in Palaeontologia Electronica.Our new study has solidified the idea that O. megalodon was not merely a gigantic version of the modern-day great white shark, Phillip Sternes, a co-author of the paper who was a graduate student at DePaul University at the time of the study, said in a press release. Sternes is now an educator at SeaWorld San Diego.The Megalodon BodyMany previous Megalodon size estimates have been based upon the most complete available fossil of the sea creature: a 36-foot-long section of vertebrates encompassing the sharks trunk, located in Belgium. The new study asks a question about proportion essentially what are the best estimates of the creatures missing head and tail, based on what we know about shark anatomy, both past and present. An international team of researchers surveyed the ratios of the head, trunk, and tail relative to total body length across 145 modern and 20 extinct species of sharks. Assuming the megalodons body structure was consistent with most sharks, they determined that the Belgium specimens length totaled 54 feet about 10 feet longer than the standard U.S. school bus.Different Body ShapeThe scientists also scrutinized specific bones to get better understanding of the megalodons likely overall body shape. Those clues gave fodder to the notion that the megalodons shape was more akin to the long, slender modern lemon shark than to the shorter stockier body of the contemporary great white meaning earlier estimate of the Belgian specimens length were probably too short.No matter the exact size, the Meg was truly a scary specimen.Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:Before joining Discover Magazine, Paul Smaglik spent over 20 years as a science journalist, specializing in U.S. life science policy and global scientific career issues. He began his career in newspapers, but switched to scientific magazines. His work has appeared in publications including Science News, Science, Nature, and Scientific American.