Megalodon: Largest Ever Shark's Diet Surprises Geoscientists
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content.
A new study has uncovered surprising insights into the feeding habits of the largest predatory fish to ever roam the Earth's oceans, challenging long-standing assumptions about the prehistoric predator.
For centuries, scientists believed that Otodus megalodon hunted exclusively at the top off the food chain, but a new study led by Jeremy McCormack from the Department of Geosciences at Goethe University Frankfurt found that its diet was far more flexible than previously thought.
Longer than a truck with a trailer (reaching up to almost 79 feet long) and weighting almost twice as much, Megalodon, ruled the oceans between 20–3 million years ago, frequently on the hunt for prey to satisfy its astonishing 100,000 kilocalories-per-day nutritional demand.
Its massive jaws were filled with triangular teeth, each the size of a hand, and its deadly bite had the force of an industrial hydraulic press, leaving no hope for any creature crossing its path.
It was thanks to its fossilized teeth that McCormack, in collaboration with other scientists from Germany, France, Austria and the US, were able to discover the apex predator's unusual dietary habits.
A stock image shows a 3D illustration of the Otodus Megalodon, the largest predatory fish that has ever existed.
A stock image shows a 3D illustration of the Otodus Megalodon, the largest predatory fish that has ever existed.
getty images
By analyzing the levels of zinc in the fossils, the study found that while Megalodon did surely feast on whales and dolphins whenever it had a chance, the shark adjusted its diet based on availability of the prey.
Zinc occurs in atomic variants (isotopes) of different weights, and is ingested with food. Less of the heavier isotope zinc-66 than the lighter isotope zinc-64 is stored in muscles and organs. Predatory fish absorb significantly less zinc-66 and those at the top of the food chain absorb even less.
"Since we don't know how the ratio of the two zinc isotopes at the bottom of the food pyramid was at that time, we compared the teeth of various prehistoric and extant shark species with each other and with other animal species. This enabled us to gain an impression of predator–prey relationships 18 million years ago," explained McCormack in a statement.
Sea bream—a fish which fed on mussels, snails and crustaceans—formed the lowest level of the food chain, followed by smaller shark species such as requiem sharks and the ancestors of today's cetaceans, dolphins and whales.
Larger sharks such as sand tiger sharks were further up the food pyramid, and at the top were giant sharks like Araloselachus cuspidatus and the Otodus shark genus, which includes Megalodon.
Results of the study showed that the levels of zinc found in the Megalodon couldn't be sharply differentiated from the lower levels of the pyramid, suggesting that the largest shark that ever lived was flexible enough to feed on both marine mammals and large fish from the top of the food pyramid as well as lower levels.
Jeremy McCormack at the mass spectrometer, which is used to determine the zinc isotope ratio. This ratio provides information about the diet of Otodus megalodon. Photo: Uwe Dettmar for Goethe University
Jeremy McCormack at the mass spectrometer, which is used to determine the zinc isotope ratio. This ratio provides information about the diet of Otodus megalodon. Photo: Uwe Dettmar for Goethe University
Uwe Dettmar, Goethe University
"Our study tends rather to draw a picture of megalodon as an ecologically versatile generalist," McCormack added.
The shark's diet also greatly varied depending on its location and regional availability of prey. The teeth used for the study mostly came from 18-million-year-old fossil deposits in the German cities of Sigmaringen and Passau—and sharks in these locations showed different food habits.
The creatures from Passau fed more on prey from lower levels of the food pyramid, probably due to lack of bigger fish in the area.
McCormack said that the new method of determining tooth zinc isotope ratios has once proven to be a valuable instrument for paleoecological reconstructions.
Kenshu Shimada, paleobiologist at DePaul University in Chicago, USA, and coauthor of the study added: "It gives us important insights into how the marine communities have changed over geologic time, but more importantly the fact that even 'supercarnivores' are not immune to extinction."
Do you have a tip on a science story that Newsweek should be covering? Do you have a question about Megalodon? Let us know via science@newsweek.com.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Newsweek
2 days ago
- Newsweek
Scientists Make World's Smallest Violin
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. Scientists in the United Kingdom have made what may be the world's smallest violin, using advanced nanotechnology. The microscopic instrument, measuring 35 by 13 microns, and constructed from platinum, is less than the width of a human hair, said Loughborough University researchers. Why It Matters The tiny violin was created to demonstrate the accuracy and versatility of a state-of-the-art nanolithography system. Kelly Morrison, the head of Loughborough University's Physics Department, said the system would allow scientists "to design experiments that probe materials in different ways—using light, magnetism, or electricity—and observe their responses." Scientists said the technology could accelerate breakthroughs in sectors such as computing and energy, allowing researchers to build and study materials at the smallest scale. The 'world's smallest violin' created by Loughborough University physicists. The 'world's smallest violin' created by Loughborough University physicists. Loughborough University What To Know The miniature violin was made using a NanoFrazor, a system that employs thermal scanning probe lithography. This technique uses a heated, needlelike tip to sculpt material at nanometer precision. According to the university's press release, the process began with a chip being covered in two layers a gel-like material. The pattern was then etched, washed and coated in platinum, then cleaned again to show the final form. Each violin took about three hours to produce after the fabrication sequence was determined, but it took months of development. The violin, which is only an image at microscopic scale, cannot produce sound. The institution said the violin had not been officially confirmed as the world's smallest, though it is smaller than the diameter of a human hair, which typically measures 17 to 180 microns (a micron is a millionth of a meter). Research projects using the nanolithography system to investigate applications—such as developing energy-efficient and faster data storage by combining advanced materials and nanoparticles—are underway at the university. Other research explores quantum materials to make next-generation memory devices smaller, faster and more reliable, and the nanolithography system helps to produce accurate test structures. The team said the knowledge gained from the violin process was vital for these advances. The expression "world's smallest violin" is often used to mock exaggerated complaints. It is believed to have originated in a 1978 episode of M*A*S*H when Major Margaret Houlihan, rubbing her thumb and forefinger together, said: "It's the world's smallest violin, and it's playing just for you," According to ClassicFM. Professor Kelly Morrison, left, with Dr. Naëmi Leo, in front of the Loughborough University nanolithography system. Dr. Leo holds the chip that features the image of 'the world's smallest violin'. Professor Kelly Morrison, left, with Dr. Naëmi Leo, in front of the Loughborough University nanolithography system. Dr. Leo holds the chip that features the image of 'the world's smallest violin'. Loughborough University What People Are Saying Kelly Morrison, the head of Loughborough University's Physics Department, said in a press release: "Though creating the world's smallest violin may seem like fun and games, a lot of what we've learned in the process has actually laid the groundwork for the research we're now undertaking." She added: "I'm really excited about the level of control and possibilities we have with the setup. I'm looking forward to seeing what I can achieve—but also what everyone else can do with the system." What Happens Next The researchers plan to use the experience and protocols established during this project in ongoing work on data storage and quantum material studies, furthering research into advanced computing technologies.
Newsweek
2 days ago
- Newsweek
'Doomsday Fish' Discoveries Spark Fears Of Impending Natural Disaster
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. The recent discoveries of two rare deep-sea dwelling oarfish have sparked fears of a looming natural disaster. The fish were discovered in separate incidents in India and Tasmania within the last week. In the first incident, fishermen in Tamil Nadu, India, pulled a 30-foot oarfish from the water. The massive fish required seven men to hold it for the video. Stock image of an oarfish. Stock image of an oarfish. Photo by Eric Broder Van Dyke / Getty Images On June 2, a dogwalker named Sybil Robertson encountered a dead nine-foot specimen washed up on a Tasmanian beach and posted photos to a citizen scientist group on social media. "I just knew it was something unusual and weird," Sybil Robertson told The Daily Mail, describing the oarfish's markings as "fabulous". A 'Doomsday' Fish? Oarfish are sometimes known as "doomsday fish"—a reputation that stems from interpretations of the oarfish in Japanese folklore. As per Forbes, at least a dozen oarfish washed up onto Japan's coastline in the year before the 2011 Fukushima earthquake and tsunami, which brought the deep-sea creatures back to the forefront of the imagination. Doomsday fish have been found in Tamil Nadu, India. — ಸನಾತನ (@sanatan_kannada) May 31, 2025 Ben Fraber, an ichthyologist and the marine vertebrate collection manager at Scripps Institution of Oceanography in San Diego, told Newsweek in a phone interview that the mythology was "compelling enough" to capture the public's attention. "You do see when there's a big change in pressure on land, birds and other animals will move out of the way," Fraber said. However, researchers in Japan took a closer look at the phenomenon, bringing in data points that included beached whales and anglerfish, as well as known natural disasters and earthquakes dating back to the early 1900s. "They found almost no correlation whatsoever," Fraber noted. "It's really interesting to think about, but it doesn't seem to have a statistical link that we can find." A Rare Find Fraber has seen oarfish in person—last year, two oarfish were discovered by employees of Scripps Institution of Oceanography who were out snorkeling for the day. The employees notified lifeguards, and the institute was able to work with the National Oceanic and Atmospheric Administration (NOAA) to bring the oarfish in. Fraber preserved the fish in formaldehyde and alcohol, and members of the public can see one of them currently in the Birch Aquarium at Scripps in San Diego. Fraber said oarfish sightings are relatively rare in Southern California—the two his team encountered were only the 21st and 22nd discovered since 1901. "Having the samples in person instead of just a video allows us to look at their stomach contents, look at their genetics, we'll get nitrogen and carbon isotopes that can tell us where they are in the open ocean food web," Fraber said. "And we preserve them so people in the future can continue asking questions from them." According to Fraber, oarfish are filter feeders whose jaws are modified so they can push them forward and vacuum water in, creating suction that traps food similar to bass or large whales. Oarfish primarily eat krill and small fish, which may be confused by the oarfish's silvery body that refracts light. "You're a little school of fish, you're swimming around, you see this thing, but it kind of just looks like a big jelly or gelatinous organism, something you're not too concerned about because a jellyfish is not going to try to eat you," Fraber said. "So you swim up and it's actually not that. It's this big fish that has a highly modified mouth that can protrude and create a kind of vacuum cleaner. It slurps up all these fish." A "Wow" Reaction Having handled and seen oarfish in person, Fraber understands the hype. "I think part of it is the size," he said. "Part of it is the look, they have this beautiful bright red fin, big silvery body, large eyes. "And part of it is the scale. We're not used to seeing animals that big—with the exception of sharks, dolphins and whales—so it elicits this kind of 'wow' reaction." Fraber noted that the mythology of sea serpents is probably related to misidentified oarfish long ago. "It's like actually getting to see this semi-mythological thing in person, it's not a myth, it's a real animal that's living with us on our planet, I think that makes it really amazing," he said. "Even though I've worked on fish for almost 20 years, and have handled many oarfish specimens, these two last year were the first time I actually got to see them fresh and unpreserved in person, and it was pretty magical."
Newsweek
2 days ago
- Newsweek
Parents Can Choose Genetic Makeup of Their Children With New IVF Option
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. A U.S.-based biotech company has unveiled a new in vitro fertilization (IVF) option that allows parents to select embryos based on genetic markers tied to health and longevity. DNA testing and analysis company Nucleus Genomics has announced the world's first genetic optimization software that "helps parents pursuing IVF see and understand the complete genetic profile of each of their embryos." Why It Matters The company says it can analyze the genetic makeup of embryos to test for up to 900 conditions including diabetes, cancer, and heart disease. By choosing embryos with the lowest risk profiles, parents can theoretically boost their children's chances of living longer and healthier lives. But the practice also raises ethical concerns about choosing embryos based on probabilities. "Nucleus Embryo is the first-ever genetic optimization software that helps parents give their children the best possible start in life—long before they're even born," the company said on X, formerly Twitter. Composite image of a fetus and the brain. Composite image of a fetus and the brain. Getty/Newsweek What To Know Prospective parents can upload up to 20 embryo DNA files from their IVF clinics for over 900 genetic analyses spanning cancers, chronic conditions, appearance, cognitive ability, mental health, and other conditions. The company then provides clients with a detailed report, which shows their embryo's results. "Sort, compare, and choose your embryos based on what matters most to you," Nucleus Genomics said. Demo pictures of the process provided by the company shows that the tests will also reveal what eye color and hair color the child is likely to have. A screengrab from Nucleus Genomics showing an in vitro fertilization option that allows parents to select embryos based on genetic markers tied to health and longevity. A screengrab from Nucleus Genomics showing an in vitro fertilization option that allows parents to select embryos based on genetic markers tied to health and longevity. Nucleus Genomics It tests for markers for common conditions like type 2 diabetes, coronary artery disease, and high blood pressure, and genetic contributions to various cancers (e.g., breast, colorectal, ovarian). It also covers mental health risks, such as depression and anxiety disorders, as well as physical traits like eye color, hair color, height, BMI, and even IQ-related markers. The test offers a comprehensive genetic profile, allowing prospective parents to compare multiple embryos on these different attributes before choosing one for implantation. "Life span has dramatically increased in the last 150 years," Kian Sadeghi, the company's founder and chief executive, told the Wall Street Journal. "DNA testing to predict and reduce chronic disease can make it happen again." The 25-year-old told the Journal he sees no distinction between individuals using DNA tests to understand their own risks and those screening and ranking embryos to select one likely to live a longer life. "It is the same underlying motivation," Sadeghi said. "It is about living a longer, healthier life." "The longevity movement is about taking medicine back and putting it in the people's hands," Sadeghi added. "Why would that not apply now to the most intimate, personal, emotional, sensitive decision you will make? Picking your baby." A screengrab of analysis by Nucleus Genomics showing a detailed report of prospective embryo results. A screengrab of analysis by Nucleus Genomics showing a detailed report of prospective embryo results. Nucleus Genomics What People Are Saying Nucleus said on its website announcing Nucleus Embryo: "My parents are immigrants from Iran who came to America with nothing but a conviction that me and my siblings would have more. But when my 15-year-old cousin suddenly died in her sleep from a preventable genetic disease, my family was powerless to save her. "My parents, grieving the loss of my cousin, were also terrified. What if my siblings and I were at the same risk? That was the first time I understood what generational health meant. "Our users don't just do Nucleus for themselves—they do it for themselves and their loved ones. Now, I'm proud to say that care can start before a child is even born." Other users on social media questioned the ethics of the technology. One thread, viewed more than 3 million times, said, "Holy s***. It's happening…you don't just pick a child. You rank them by longevity potential." Emma Waters, a policy analyst at The Heritage Foundation, responded to tweets about the project. "'I only wanted you because you were a girl and the right kind of healthy. I destroyed the other 19 human embryos that your father and I created.' "Don't worry, it's 'not eugenics,' it's only science." 'I only wanted you because you were a girl and the right kind of healthy. I destroyed the other 19 human embryos that your father and I created.' Don't worry, it's 'not eugenics,' it's only science. — Emma Waters (@emlwaters) June 5, 2025 Asked for her definition of eugenics, she said, "The selection or rejection of a living human being based on certain traits or conditions. I.e., choosing which embryos live and which ones are destroyed based on factors like health, sex, and IQ." What Happens Next Polygenic embryo screening is largely unregulated in the U.S., and it is likely to remain that way for the foreseeable future.
