This Is Where the Biggest of All Megalodons Lived

Scientists have revealed where the biggest of all ancient megalodon sharks lived.

Otodus megalodon was a massive species of shark that could grow to between 50 and 65 feet long.

A study published in the journal Historical Biology has shown that the biggest of all the megalodons lived in cooler waters, far from the equator.

Researchers examined megalodon teeth found in modern-day locations, such as the Carolinas, California, Maryland, Spain, Peru and Panama. They then estimated the body size of each to find that the largest of the very large predatory fish occurred at higher latitudes, such as the eastern coast of the U.S.

"The common notion that the species reached 18-20 meters (59-65 feet) should be applied primarily to populations that inhabited cooler environments," lead author and paleobiologist Kenshu Shimada of the DePaul University in Chicago said in a statement.

Megalodons first appeared in the fossil record around 20 million years ago. The species likely went extinct between 4 and 3.2 million years ago. No one knows precisely why, but competition with the modern great white shark and ancient climate change have both been suggested as reasons.

Fossils of megalodon teeth have been found on both coasts of the U.S. They are typically used by paleontologists to infer more details about the animals from their size to their body shape.

The authors said that megalodon sizes in the study seemed to match Bergmann's Rule—a principle founded by German biologist Carl Bergmann, who said that body size often depends on latitude. Larger animals are often found in colder parts of the world because their size helps them retain heat better than smaller animals.

The authors said their study could be the first time the rule had been proved for the Elasmobranchii family of sea creatures, which include sharks and rays. They said that the findings showed a new scientific reason for why megalodons grew so big—their great size helped them manage their body temperatures better in colder environments.

The research also showed more evidence for how larger sharks may be adapting to climate change. A recent study showed how tiger sharks were being seen much further north than previously as the ocean temperatures rise. Great white sharks are also being found on more northerly coasts as the sea heats up.

"[T]he results of this study have important implications for understanding how modern climate change is rapidly accelerating marine habitat shifts to more polar latitudes in apex predators such as sharks," co-author Michael Griffiths, also of William Paterson University, said in a statement.