Scientists find new evidence for what led to the megalodon’s demise

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Megalodon, one of the scariest sharks that ever lived, wasn’t the cold-blooded killer it was made out to be—at least not in the literal sense of the word.

By analyzing fossilized megalodon teeth, scientists have discovered that the extinct shark was partially warm-blooded, with a body temperature about 7 degrees Celsius (44 degrees Fahrenheit) warmer than seawater temperatures estimated at the time, according to A study published last week In Proceedings of the National Academy of Sciences.

“We found that O. megalodon had significantly elevated temperatures compared to other sharks, consistent with a degree of internal heat production as modern warm-blooded (endothermic) animals.” study co-author Robert Eagle, professor of marine sciences and geobiology at UCLA, said in an email.

The results indicate that this distinctive trait played a major role in the ancient predator Terrifying size – and its eventual disappearance.

Otodus megalodon, also known as the megalodon shark, is believed to have been at least 15 meters (49 ft) long, and was one of the largest Apex marine predators since the Mesozoic Era and became extinct about 3.6 million years ago, according to eagle.

Scientists previously assumed that megalodons were warm-blooded, but the new study is the first to provide concrete evidence of this effect.

The researchers noted how closely the carbon-13 and oxygen-18 isotopes found in fossilized ancient shark teeth are bound together—a data point that can reveal how warm the body is. From this result, they concluded that the average body temperature of Megalodon was about 27 °C (80 °F).

Like modern white and mako sharks, so were the megalodons Regionally endothermicWhich means they have the ability to regulate temperature in specific parts of the body, according to the study. In contrast, the body temperatures of other cold-blooded predators are regulated by the temperature of the water around them.

Being warm-blooded may be one of the main factors fueling megalodon’s sheer size and overall prowess as predators, according to senior study author Kensho Shimada, a paleobiologist at DePaul University in Chicago.

“The large body enhances efficiency in capturing prey with wider spatial coverage, but it requires a lot of energy to maintain,” Shimada said in an email. “We know that Megalodon had giant cutting teeth used to feed on marine mammals, such as cetaceans and cetaceans, based on the fossil record. The new study is consistent with the idea that warm-blooded evolution was a gateway for megalodon’s giants to keep up with its high metabolic demand.”

For such a massive animal, having to constantly use so much energy to regulate its body temperature may have contributed to its downfall as the world changed. The researchers said the timing of the megalodon’s extinction coincided with a drop in global temperature.

“The fact that megalodon is gone points to the potential vulnerability of being warm-blooded because warm-blooded animals require constant food intake to maintain a high metabolism,” said Shimada. “There is likely to be a shift in the marine ecosystem due to climatic cooling,” causing sea levels to drop, changing the habitats of the food species they feed on such as marine mammals, and leading to their extinction.

Compared to other apex predators, megalodon was much larger and therefore more susceptible to changes in prey populations, said study lead author Michael Griffiths, a professor of environmental sciences and a geochemist and paleoclimatologist at William Patterson University in New Jersey.

But knowing more about the ancient shark can help scientists better understand the threats that similar marine animals face today.

“One of the big implications of this work is that it highlights the vulnerability of large predators, such as the modern great white shark, to climate change given their similarities in biology to megalodon,” said Griffiths.