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The biggest megalodon tooth ever found was a staggering seven inches - roughly the same size as the average male human hand.
Despite the megalodon going extinct roughly three million years ago, thanks to a drop off in the food chain, scientists are still learning about one of the most feared creatures of the deep.
Researchers from the University of Bristol have now discovered the megalodon teeth grew so big as a result of the shark becoming so huge.
Scientists had thought that the teeth became so big thanks to a change in the shark s diet, but researchers now know that not to be the case.