Extinct megalodon shark may have been up to 65-feet long, new estimates find

When megalodon was first described as a species, scientists thought it was the direct ancestor of the great white shark. Although the two species have similar teeth and feeding habits, they last shared a common ancestor about 60 million years ago, Perez said. (IMAGE COURTESY OF TIM SCHEIRER/CALVERT MARINE MUSEUM)

GAINESVILLE, Fla. – A high school lesson using a more reliable way of estimating the size of a megalodon found the massive extinct shark may have been bigger than previously thought.

Earlier studies estimated the shark to be between 50 to 60 feet long, but the revised estimate found that the megalodon could have measured up to 65 feet, nearly the length of two school buses, according to the University of Florida.

Victor Perez, then a doctoral student at the Florida Museum of Natural History, was guiding students through a math exercise that used 3D-printed replicas of fossil teeth from a real megalodon and a set of commonly used equations based on tooth height to estimate the shark’s size. But something was off: Students’ calculations ranged from about 40 to 148 feet for the same shark. Perez snapped into trouble-shooting mode.

“I was going around, checking, like, did you use the wrong equation? Did you forget to convert your units?” said Perez, the study’s lead author and now the assistant curator of paleontology at the Calvert Marine Museum in Maryland. “But it very quickly became clear that it was not the students that had made the error. It was simply that the equations were not as accurate as we had predicted.”

Although the equations have been widely used by scientists since their publication in 2002, the classroom exercise revealed they generate varying size estimates for a single shark, depending on which tooth is measured.

“I was really surprised,” Perez said. “I think a lot of people had seen that study and blindly accepted the equations.”

For more than a century, scientists have attempted to calculate the size of megalodon, whose name means “big tooth.” But the only known remains of the fearsome shark that dominated oceans from about 23 to 3.6 million years ago are fossilized teeth and a few, rare vertebrae.

To read more, visit the Florida Museum of Natural History.