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How the great white shark drove the mighty megalodon to extinction
The mammoth predator, also known as the meg and which grew to be bigger than a London bus, went extinct around 3.6 million years ago
Bigger than a double-decker bus and weighing 50 tons, the megalodon was one of the most fearsome oceanic predators ever known. Yet its extinction 3.6 million years ago may have been brought about by a much smaller leviathan of the deep.
Fresh analysis shows the emergence of the great white shark, another apex predator that is a third of the size of "the meg", may have been the reason for the larger creature’s extinction.
Experts from the Max Planck Institute for Evolutionary Anthropology in Germany studied the amount of zinc in the teeth of both the shark species. Zinc is a natural part of the diet, less common in predators than in prey.
“Our results show that both megalodon and its ancestor were indeed apex predators, feeding high up their respective food chains,” says Prof Michael Griffiths, the study co-author and a professor at William Paterson University.
He also said it was “truly remarkable” that the megalodon and great white, despite one being three times the size of the other, were rivals that co-existed for a time, duelling it out for oceanic supremacy.
Prof Kenshu Shimada, from DePaul University in Chicago, a co-author of the paper, added: “These results likely imply at least some overlap in prey hunted by both shark species.
“While additional research is needed, our results appear to support the possibility for dietary competition of megalodon with early Pliocene great white sharks”.
The sharks were likely both hunting whales and dolphins, with competition leading to not enough food to be shared between the two animals.
This, as well as climate change, likely led to the megalodon being unable to support its vast size and forcing it into oblivion, the researchers say.
Writing in their study, published in Nature Communications, the researchers say: “Diet and resource competition have been discussed as possible drivers of [the megalodon’s] evolution and extinction, but its abrupt disappearance in the fossil record remains an enigma.
“In this study, we use zinc isotopes to compare the dietary ecology of... megalodons to that of the great white shark.
“If these apex predators fed at similarly high trophic levels, there is the possibility of resource competition.
“Further, the extent of trophic variation within and between localities could yield important clues to trophic dynamics, ecological plasticity, and evolutionary “success.”
A study from 2021 found that megalodon sharks gave birth to babies bigger than most adult humans after they feasted on unhatched eggs in the womb.
Prof Shimada, who led this study, said at the time: "As one of the largest carnivores that ever existed on Earth, deciphering such growth parameters of megalodon is critical to understand the role large carnivores play in the context of the evolution of marine ecosystems."
His team studied the vertebrae of a megalodon and found 46 growth rings, indicating it was 46 years old. By counting backwards, they calculated that as a result, it was about six and a half feet long at birth.