It’s a puzzle piece that has eluded shark scientists for years: just why exactly did the ancient Otodus megalodon, the largest shark to ever swim in our planet’s oceans, disappear? While recent movies and mockumentaries have toyed with the idea that “the Meg” is still alive, it is unquestionably extinct according to marine biologists. Theories have been proposed ranging from lack of prey to mass extinction events. Extinct or not (as some conspiracists believe), the nearly 60-foot-long creature captures everyone’s attention. Especially that of Robert Boessenecker, a paleontologist at the College of Charleston in South Carolina who found an Otodus megalodon tooth in California and began searching for more evidence of this animal in the West Coast. Boessenecker and colleagues then expanded their hunt even further, broadening the horizons to learn about how such a giant shark could pull off what may be one of the best disappearing acts of the planet.
But megalodon is an ancient magician that has cast many researchers under its spell, including Catalina Pimiento of the University of Florida and Christopher Clements of the University of Zurich who in 2014 published their analysis of the ancient animal’s extinction using available records. Their team of researchers determined that megalodon could have still inhabited our oceans up to around 2.6 million years ago, which is about a half million years or so before our human relatives Homo erectus began forging a path in this planet. The previous research suggested that there was a mass-extinction event around this time caused by radiation from a nearby supernova that led not only to the death of this predator but of many other animals such as ancient seals, walruses, dolphins, and whales. “The extinction of O. megalodon was previously thought to be related to this marine mass extinction-but in reality, we now know the two are not immediately related,” explained Boessenecker.
What started out in a sandy beach in California for Boessenecker and a curiosity has led to an answer that took the internet by storm: megalodon vanished some 3.6 million years ago, which is a million years earlier than any other previous estimates. Published in the journal PeerJ, this timeline means as the megalodon fell… the animal we know today as the modern great white shark (Carcharodon carcharias) rose. Could this be the culprit to what ultimately shook up our ancient marine ecosystems and spelled doom out for megalodon? Boessenecker and the team believes so.
“We propose that this short overlap (3.6-4 million years ago) was sufficient time for great white sharks to spread worldwide and outcompete O. megalodon throughout its range, driving it to extinction—rather than radiation from outer space,” said Boessenecker in a statement. “This is much more believable and robustly supported by the data,” agreed Tom Deméré, giving a comment to National Geographic. Deméré is a curator of paleontology at the San Diego Natural History Museum and who was a reviewer of Pimiento and Clement’s 2014 study.
But that isn’t the only culprit in this extinction. Although the publication argues that adult great whites “would have been in the same size range and likely would have competed with juvenile Otodus megalodon,” it also points the finger at dwindling prey items (the small whales that megalodons ate) and what scientists know as range fragmentation, which is when populations of a species get split up into separate areas. The researchers claim the fossil record has been misinterpreted in previous studies, with Boessenecker commenting: “We used the same worldwide dataset as earlier researchers but thoroughly vetted every fossil occurrence, and found that most of the dates had several problems—fossils with dates too young or imprecise, fossils that have been misidentified, or old dates that have since been refined by improvements in geology.”
As the megalodon population became fragmented, the large predators had to fight for dwindling food not only against one another but the newly emerged and much smaller great white shark. Although smaller, great whites are just as fierce as any other shark and their reduced size and possible increased agility may have given them the upper hand. Both animals ate similar prey, meaning the megalodon stood no chance against the newest competitor. Carcharodon carcharias evolved around four million years ago, with some scientists estimating they ventured out of the Pacific Ocean around two million years ago. Leaving the confines of the Pacific was a step towards total world domination as they spread around the world over hundreds of thousands of years. Today, the great white shark remains a cosmopolitan shark and frequently makes the news for kills. Guess this may be another one it can add to the list.
Who thinks the next “Baby Shark” hit should be “Extinct Shark”? Megalodon may not be a fan, though.