In a study published today in the journal Earth and Planetary Science Letters, paleontologists examined the ratio of two distinct zinc isotopes in the enamel of 19 dental species from early Miocene marine ecosystems, including the Megatooth Sharks Otodus Megalodon and Otodus chubutensis.
Otodus Megalodon became extinct 3.6 million years ago. Image credit: Alex Boersma/PNAS.
Otodus Megalodon was a colossal megatooth shark that inhabited the world’s oceans from 23 to 3.6 million years ago.
It could reach a length of at least 15 meters, making it one of the largest apex marine predators since the Mesozoic Era.
“Otodus Megalodon,” stated Dr. Jeremy McCormack from Goethe University in Frankfurt, “was estimated to require about 100,000 calories per day.”
“Scientists have generally believed that megalodon primarily consumed whales.”
“At least, that’s what it depended on if whales were available for extended periods.”
“However, it seems that Megalodon had a much broader range of prey than previously thought.”
In the recent study, Dr. McCormack and his colleagues investigated the ratio of zinc-64 and zinc-66 isotopes in the dental enamel of 19 fossil species from sediments that are 20.4 to 16 million years old, discovered in the shallow waters of the Burdigalian seaways in what is now southern Germany.
“Zinc is ingested through food, which means the heavier zinc-66 is stored in muscles and organs,” they explained.
“As a result, fish that consume other fish accumulate a high amount of zinc-66. Therefore, those that eat them will have even less.”
“This is why Otodus Megalodon and its relative Otodus chubutensis exhibited the lowest ratios of zinc-66 to zinc-64 at the top of the food chain.”
“Seabreams that fed on mussels, snails, and crustaceans represented the lowest level of our food chain study,” Dr. McCormack noted.
“Following that were smaller shark species, including Requiem sharks, and the ancestors of modern whales, dolphins, and porpoises.”
“Larger sharks, such as sand tiger sharks, occupied higher levels of the food pyramid, with immense sharks like Aralosera coscuspidatus and Otodus sharks containing Megalodon at the top.”
“However, Otodus sharks cannot be distinctly differentiated from lower levels of the pyramid.”
“Megalodons were versatile enough to consume marine mammals and large fish, depending on their availability from both the upper and lower tiers of the food pyramid.”
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Jeremy McCormack et al. The vegetative ecology of Miocene marine vertebrates reveals the Megatooth Shark as an opportunistic hypercarnivore. Earth and Planetary Science Letters Published online on May 26, 2025. doi:10.1016/j.epsl.2025.119392
Source: www.sci.news
