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What scientists understand about the greedy feeding habits of the giant megalodons could rise for some modification.
Prehistoric predators, which were extinct about 3.6 million years ago, don’t hunt only large marine mammals like whales as researchers have widely considered, new research is discovering. Instead, fossilized tooth minerals reveal that megalodon could have been an opportunistic feeder to meet the surprising 100,000 calories per day requirement.
“If available, they would probably have taken large prey items, but if not available they were flexible enough to eat small animals to meet dietary requirements,” said Jeremy McCormack, an earth scientist at Goethe University in Frankfurt, Germany.
The study was published in the Journal Earth and Planetary Science Letter on Monday, and also shows regional differences in the feeding habits of giant sharks. The finding suggests that megalodons pursue what was in local waters, greeting other top predators and smaller prey.
“They weren’t focused on any particular prey species, but they must have fed a lot of different species into the entire food web,” McCormack said. “It’s certainly a fierce apex predator, and while perhaps no one else would prey on adult megalodons, it’s clear that they could potentially feed almost everything else they swam themselves.”
Megalodon sent prey with ferocious bites and deadly serrated teeth. The super predator’s teeth, rich in the fossil record, were used by McCormack and his colleagues to conduct geochemical analyses, unlocking fresh clues that could challenge Megalodon’s role as the sole king of the ancient sea.
It is not the first time that research has challenged previous knowledge of giant sea creatures. In fact, since no complete fossils have been found, many questions remain unanswered about the name of the scientific species meaning “giant teeth.” The lack of hard evidence is not formed very well, as it is due to the fact that the fish’s skeleton is made of soft cartilage rather than bone.
Recent studies have found, for example, animals are warm-blooded than other sharks, with continued debate about their size and shape. The scientists who created the 3D reconstruction suggested that in 2022 the Megalodon was about three times the length of the great white shark, about 52 feet (16 meters). However, a survey in March assumed that Mega Shark was actually much larger, with 2018 blockbuster The Meg being up to 80 feet (24 meters) long, longer than the fictional version.
According to McCormack, determining what you eat based on fossil evidence poses a challenge for megalodon feeding habits. “We know they fed big marine mammals from teeth biting marks,” he said. “Of course, you can see bite marks of marine mammal bones, but sharks don’t have bones so they can’t see them when feeding other sharks. So there’s already a bias in the fossil record of this species.”
To gather more about Megalodon’s prey selection, McCormack and his co-authors saw the fossilized teeth of giant sharks and compared them to the teeth of other animals that lived at the same time, as well as other predators such as modern sharks and dolphins. Researchers used specimens from the museum collection and samples of animal corpses on the beach.
Specifically, the research team conducted a lab analysis of zinc, a mineral that is only acquired through food.
Zinc is essential for living organisms and plays an important role in dental development. The proportion of heavy zinc isotopes in shark teeth enamel holds a record of the type of animal they ate.
Different types of zinc, or isotopes, are absorbed when eaten by fish and other animals, one of them – zinc 66, is stored in much less tooth enamel than zinc 64. The ratio of these zinc isotopes expands further away from the lowest level of the food chain. This means that other fish eaters have lower levels of zinc 66 compared to zinc 64, while those fish eaters have even fewer zinc 66 compared to zinc 64. A marker that helps you create sequences of food chains.
Researchers found that seabream, a fish that eats mussels and crustaceans, is at the bottom of a reconstructed chain, followed by a small shark. From the genus Carcharhinus, up to 9.8 feet (3 meters) in length; And an extinct tooth whale that rivals modern dolphins.
Furthermore, although a large shark, like Galeoco Adunkas, resembling modern tiger sharks, was further upwards, occupying the upper slots, its zinc ratio was not so different to suggest a large gap with lower animals. “Based on our new results, we can see that it is clear that it can feed the top, but it was flexible enough to feed even at low (the level of the food chain),” McCormack said.
Furthermore, researchers found that megalodons are not alone at the top of the food chain, but instead share spots with other “opportunistic ultra-otolaryngology” such as the nearby relative otodus chubutensis, the lesser known Alaroseratus cuspidatus, another giant fish-eating shark.
That revelation challenges the assumption that Megalodon is the exclusive ruler of the ocean, drawing comparisons with another big opportunistic feeder, the Great White Shark. According to paleontologist Shimizujima Kenshu Island, one of the co-authors of the latest research, the finding also reinforces the idea that the rise of the earth could be a factor in the extinction of megalodon.
“It is hypothesized that one of the contributing factors for the end-of-megalodon mise is the rise of the Great White shark, which transitions to marine mammals as they eat fish when they are young and eat their diets bigger.”
“Our new research showing the ‘diet overlap’ between great white sharks and megalodons reinforces the idea that the evolution of the great, great, great sharks, which is smaller, more agile and manipulated, can actually exterminate (drifted) megalodons. ”
The new study will allow scientists to replicate snapshots of marine food networks that existed around 20 million years ago, according to Jack Cooper, a UK-based paleontologist and a megalodon expert who was not involved in the study.
“The general photo of the Megalodon was of a giant shark munching a whale,” Cooper said in an email. “This study adds a new dimension that Megalodon probably had a wide range of prey. Essentially, it probably ate what it wanted, not just whales.”
Another interesting find he added is that the diet of megalodons has probably changed slightly between different populations, which are observed in today’s great white sharks. “This makes sense and it’s something that we probably would have hoped for as Megalodons live all over the world and not all of their prey did. But it’s great to have specific data to support this hypothesis,” Cooper said.
The study adds a lot of evidence that shapes beliefs in general about megalodon and its relatives, said Alberto Coraletta, a researcher in the Faculty of Earth Sciences at the University of Pisa, Italy, who is not involved in the study.
“These have now come to abandon the traditional reconstruction of megatooth sharks as “swelled” versions of modern white sharks. I know that megalodons are something else in terms of size, shape, ancestry and biology,” Korareta said in an email.
“The Miocene ecosystem in question did not work in a fundamentally different way compared to modern counterparts.
“That being said, it is still useful to recognize that MEG’s understanding is essentially limited to its ubiquitous teeth, several vertebrae, and a small number of scales. What you’d like to see coming out of “the abandonment of the mist of time” is the perfect MEG skeleton.