Megalodon monster sharks with a length of 20 m can compete for prey from smaller white sharks, leading to extinction.
Megalodon is the top predator in the ancient ocean. Image: iStock
Megalodon was a giant shark that lived 23 million years ago and was four times larger than today’s great whites. However, when coexisted, these two shark species are more likely to hunt the same prey. This competition may have caused the 20-meter megalodon shark to become extinct, according to the results of a new study published in the journal Nature. Nature Communications June 1st.
To draw their conclusions, the team used a new technique. They analyzed the dietary traces in the teeth of 13 extinct shark species and 20 modern shark species to find out where they were in the food chain.
“Megalodon is often depicted as an oversized shark monster in movies, but in reality, we know very little about this extinct shark,” said Kenshu Shimada, a professor of paleontology at the Museum Sternberg natural history in Kansas, study co-author, said. “Our new study shows that the diet of the early great white shark is very similar to that of a megalodon.”
Shimada and his colleagues were able to find this information by looking at the existence of different isotopes of the element zinc in the enamel of sharks. Zinc is essential for living organisms and plays an important role in bone development. The ratio of heavy and light isotopes of zinc in teeth reveals the type of prey the shark eats.
The zinc isotope can be used as an ecological indicator because the ratio of the two different isotopes varies along the food chain, says study co-author Michael Griffiths, geochemist and professor in the Department of Science Environmental Studies at William Paterson University, New Jersey.
For example, if megalodon ate great white sharks, their higher position in the food chain would be reflected in isotope ratios. But the study found that the two types of sharks overlap, suggesting they hunt the same prey. However, the team did not rule out the possibility that the megalodon hunted great white sharks.
Eating the same prey doesn’t necessarily represent direct competition between megalodon and great white. However, at least the two species certainly overlap in terms of food. Given their smaller size, great whites don’t require as much food as megalodon. So they will have a competitive advantage when hunting the same prey, Griffiths said. According to the team, the technique of using zinc isotopes could be applied to many other extinct animals to understand their diet and ecology.
An Khang (Follow CNN)
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