Megalodon. The slot very name conjures awe: A giant shark that once dominated the world's oceans, big enough to swallow a human whole. Such a beast – known only from teeth and vertebrae that survived the 3.6 million years since it went extinct – must have been fearsome indeed.

It was one of the largest carnivores ever to have lived… and yet, there is one predator still living today whose very existence may have brought the mighty megalodon (Otodus megalodon) to its fins: the great white shark (Carcharodon carcharias).

Recent research found that the two animals lived contemporaneously, suggesting that the great white shark may have played a significant role in the megalodon's decline simply by occupying the same ecological niche – living in the same habitats, and hunting the same food.

Now a new study, using a different metric – the isotope ratios of zinc in the animals' teeth – has come to the same finding. This constitutes more evidence that great whites were instrumental in sending the megalodon to a watery grave.