What did a megalodon eat

The fateful diet of the megalodon

Pisa / Vienna - Carcharocles megalodon was probably the largest shark the seas have ever seen. The Greek name megalodon can be translated as giant tooth, and that is no coincidence: the gigantic predator's fossil teeth are 18 centimeters long and are likely to have adorned a three meter wide and two and a half meter high set of teeth. C. megalodon snapped shut with a bite force of up to 180 kilonewtons, as simulations have shown.

The species from the mackerel shark family also reached respectable dimensions in other respects: at up to 18 meters, it was about three times as long as a full-grown great white shark and, when it was alive, 23 million to 2.6 million years ago, it was undoubtedly at the top of the marine food chain . Why the shark, which may once have been widespread, finally disappeared completely on the Pliocene-Pleistocene border has been the subject of numerous scientific investigations for many years.

Many paleontologists see an important factor in the climate change that this section of the earth's history brought with it. An international research team led by Alberto Collareta (University of Pisa) has now indirectly confirmed this assumption in the journal "Palaeogeography, Palaeoclimatology, Palaeoecology": According to this, the giant top hunter's specialization in small marine mammals (especially whales) could have been fatal, which do not change the sea temperature had grown.

Migratory whales

Megalodon hunted dwarf baleen whales at least off the coast of what is now Peru. This is indicated by fossils of the extinct, approximately five-meter-long species Piscobalaena nana, on which Collareta and colleagues were able to detect bite marks of the basking shark for the first time. It was previously assumed that baleen whales were on Megalodon's menu.

With over 20 known genera, an enormous variety of these whales had developed during the basking shark's lifetime. However, a number of species, especially smaller ones, fell directly victim to the climatic changes. The habitat of animals living near the coast changed dramatically as a result of the cooling: The increasing ice formation around the poles caused the sea level and the water temperatures to drop, and the year-round lush food sources became, at best, seasonal feeding grounds. These new conditions favored larger, faster whales that could make long journeys to other realms. Smaller species that were not prepared for it, however, were left behind.

Unusual competition

"The basking shark's disappearance could have been triggered by the demise of small to medium-sized baleen whales in favor of modern, large whales," says Collareta. And even if Megalodon hunted large whales, as modern great white sharks do, he could not follow them into even cooler waters.

And another factor may have contributed to the extinction of the largest shark: competition. Little by little, new, better adapted predators appeared in the seas, such as the ancestors of today's killer whales and the great white shark. (David Rennert, January 16, 2017)