Megalodon

Megalodon is the largest predatory shark in the history of the Earth. The size of the prehistoric fish has been tried many times. In 1909, when the jaw of megalodon was first reconstructed, the length of the shark's body, according to scientists' estimates, was 30 meters. Today's advances in vertebrate biology and new findings of megalodon remains have reduced the estimated size by half. With different methods of studies of the predator's teeth, we get body lengths ranging from 13 meters to 18. Only in 2015, after studying a large sample of teeth, an average length of 10 meters and a maximum length of 15 meters was obtained. By comparison, the great white shark can theoretically reach seven meters in length. The size of the megalodon approaches that of the largest Mesozoic marine reptiles, such as mosasaurs and ichthyosaurs.

Why do we use a shark's teeth rather than its skeletal parts for size estimation? Because sharks are cartilaginous fish. That is, their skeleton is made up of cartilage, not bones. Cartilage is not well preserved. They decompose before they become stony. So we have almost no megalodon remains, except teeth.

For a long time, the mass of the megalodon has been a matter of debate. It is difficult to draw conclusions about mass based on the animal's teeth alone. The lack of remains of the giant predator hindered accurate estimates. If we reconstruct the megalodon based on the composition of the white shark, we get a body mass of 41 to 47 tons. But we can compare the dimensions of the megalodon and the whale shark to draw conclusions about the mass of the extinct fish. This method underestimates the weight by up to 30 tons. Still, at that mass, the predator must have consumed a colossal amount of food, more than a ton per day. While studying the fossils of whales, the same age as the megalodon, it became clear where the shark was getting so much food. Many skeletal remains of large marine mammals had characteristic lesions that matched the profile and size of the megalodon's teeth.