The study, which makes use of a pioneering technique for analyzing sharks, has now been published in the international journal Historical Biology.

Megalodons swam the Earth roughly 15 to 3.6-million years ago, and are often portrayed as super-sized monsters in films such as 2018’s “The Meg.” While there is no dispute that they existed or that they were gigantic, Otodus megalodon are known only from their fossilized teeth and vertebrae. Based on this evidence, studies suggest they reached lengths of up to 65 feet.

Unfortunately, additional fossil evidence from which to draw conclusions about their bodies, such as a complete skeleton, has not yet been discovered.

“The cartilage in shark bodies doesn’t preserve well, so there are currently no scientific means to support or refute previous studies on O. megalodon body forms,” said Phillip Sternes, a UCR organismal biologist and lead author on the study.

Traditionally, researchers have modeled Megalodon bodies on those of modern great white sharks. Great whites are partially warm blooded and belong to the lamniform shark order. Megalodons also belong to this order, and it is believed they shared this partial warm bloodedness with great whites.

It was previously thought having some warm blood is an advantage that could expand sharks’ swimming range, unlike other fish dependent on water temperature. However, it is now believed to increase swimming speed.

“Great whites are among the fastest swimming sharks, so Megalodons were likely also big, fast sharks you would not want to run into in the open ocean,” said Sternes.

There are eight families of Lamniformes, and 15 species. Previous research took five species of warm-blooded Lamniformes, averaged their fin and body shapes and proposed a general model for Megalodons.

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