We’ve yet to spot any such refuse, if it even exists.īut these realities can’t extinguish the Meg’s enduring myth (and summer movie franchises). Even if we rarely spy creatures like giant squids, which live in the more forgiving upper ranges of what we’d call the deep sea, they leave markers of their existence strewn around the world in the form of carcasses (and bites taken out of unlucky critters).
“Ocean giants that we do know about have global distributions,” McClain says. Yet even if Meg had assumed a slender and slow disguise, we’d probably have seen evidence of it by now. Here’s how it stacks up against some modern ocean meat eaters. We’ve adjusted our estimates of the shark’s size over the years, but most experts now suspect it stretched about 50 feet long. Megalodon was a massive fish, but it wasn’t the biggest predator ever seen in the seas. Yet animals near the ocean floor have to get by on teensy scraps, preying on the scant species that live there or hoovering up biological detritus that sinks down from carcasses above. Meg may have weighed as much as three times more, and would have presumably required proportional grub. That predator’s active ocean cruising generates enough body heat to keep it toastier than surrounding seawater, an effort that burns through the equivalent of about six pounds of flesh a day. Preliminary geochemical analysis of isotopes in remains, which can help scientists estimate the body temperature of prehistoric organisms, indicates that megalodon was “warm-blooded” in the same sense as the great white. For one thing, Shimada says, its ravenous metabolism would need to fundamentally change. If the megalodon were living in the dark, inky depths, though, it would have had to become a very different sort of creature-one we might not find nearly as cinematic. Less imposing critters have indeed shown up unexpectedly in 1938 biologists identified a living coelacanth-a species of fish presumed extinct for about 65 million years. While the idea of a deep-dwelling ancient creature is highly improbable, he says, the sliver of possibility is still tempting. Even though satellites have mapped 100 percent of its floor, a low-resolution chart alone doesn’t give us great insight into what actually lives there, says Louisiana Universities Marine Consortium Executive Director Craig McClain, who specializes in cataloging oceanic systems. Believers have at least one thing right: The bottom of the sea is an enigma.
The lack of certainty helps some maintain hope of finding one in the deep. These air breathers had to break through the surface for oxygen, so paleontologists expect megalodon, like them, hung out near the shore. The species’s dietary habits further confirm a shallow lifestyle, with gnawed ancient whale bones showing Meg’s preference for marine mammals. “Remains generally come from coastal marine rock deposits formed in tropical-temperate areas,” says DePaul University shark researcher Kenshu Shimada. Save for the outliers found by the Challenger, the megalodon’s fossil record indicates it was a shore-hugging creature, similar to its distant cousin the great white. But thanks to new analyses of where it sits on the shark family tree, the predator scientists know now is very different from the Jaws star. For decades Otodus megalodon has been depicted as an oversize great white. Other scientists have since dismissed this dating, but unscrupulous documentarians and curious amateurs still highlight the research as a hint that Meg might persist. In 1959, zoologist Wladimir Tschernezky, who made a hobby of researching “hidden animals” like Bigfoot, estimated the specimens were just 11,300 years old. In 1875, during an expedition for the Royal Society of London, the HMS Challenger dredged up 4-inch-long teeth from a depth of 14,000 feet near Tahiti. Discoveries around the world-in locations as diverse as Panama, Japan, Australia, and the southeastern United States-piled up over time, but one particular find raised the specter of a Meg still swimming in the deep.
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