Megalodons were slow-swimming, warm-blooded predators – study

The placoid scales are not seen on speedier shark species, as those species have scales with spaced ridges. 

 An artistic illustration of the megalodon shark, one of the largest sharks to ever lurk in Earth's oceans. (photo credit: Wikimedia Commons)
An artistic illustration of the megalodon shark, one of the largest sharks to ever lurk in Earth's oceans.
(photo credit: Wikimedia Commons)

Once considered to be the ocean’s greatest predator, the now-extinct megalodon might not have had every natural advantage, a study published in late June found.

The peer-reviewed study, published in the academic journal History Biology, found that the iconic predator was a slow-moving creature that used its warm temperature to aid digestion and nutrient absorption.

It was likely the creature's metabolic aid that contributed to its enormous size.

About the Megalodon

The megalodon, which is also commonly referred to as the ‘megatooth shark,’ inhabited the oceans 15-3.6 million years ago. 

It is believed that the average length of the adult megalodon was 20 meters.

Women stand inside the jaws of a megalodon, an extinct species of the shark, as they visit the international exhibition titled ''Planet Shark: Predator or Prey'' at the Military-Historical Museum of Artillery, Engineer and Signal Corps in St. Petersburg, October 31, 2013. The exhibition includes colle (credit: REUTERS/ALEXANDER DEMIANCHUK)
Women stand inside the jaws of a megalodon, an extinct species of the shark, as they visit the international exhibition titled ''Planet Shark: Predator or Prey'' at the Military-Historical Museum of Artillery, Engineer and Signal Corps in St. Petersburg, October 31, 2013. The exhibition includes colle (credit: REUTERS/ALEXANDER DEMIANCHUK)

Big fish, tiny scales 

The megalodon had tiny scales known as ‘placoid scales’, which were the basis for the hypothesis in this ground-breaking study. Before this scientific undertaking, it was believed that the megalodon was partially warm-blooded, regionally endothermic, and fast-swimming.

The placoid scales are not seen on speedier shark species, as those species have scales with spaced ridges. 

“Our big scientific findings come from ‘tiny evidence’ as small as grains of sand,” said researcher Professor Kenshu Shimada, DePaul University, said to science media outlet SciTechDaily. “This led my research team to consider O. megalodon to be an ‘average swimmer’ with occasional bursts of faster swimming for prey capture.”

Despite not contributing to the speed of the creature, the study suggests that the scales had a crucial function; digestion, and absorbing and processing nutrients.

“It suddenly made perfect sense,” said Shimada. “Otodus megalodon must have swallowed large pieces of food, so it is quite possible that the fossil shark achieved the gigantism to invest its endothermic metabolism to promote visceral food processing.”