With teeth the size of a human hand and a potential length of 20 meters (66 feet), the terrifying megalodon was the biggest shark to have ever existed. Megalodon was the most apex of apex predators, according to new research examining the megalodon's teeth.
Scientists may determine a creature's position in the food chain by examining the amounts of nitrogen isotopes present in its cells. This is because nitrogen-15 builds up as one moves up the food chain due to the way nitrogen is digested and expelled.
The megalodon's (Otodus megalodon) tooth enamel reveals significant nitrogen-15 concentrations and a position at the top of the food chain. In fact, to support the megalodon, which lived from around 23 million years ago to approximately 3.6 million years ago, the food chain would have needed to be many tiers higher than it is now.
"We're used to thinking of the largest species – blue whales, whale sharks, even elephants and diplodocuses – as filter feeders or herbivores, not predators," says UK researcher Emma Kast, a biogeochemist at Cambridge University.
"But megalodon and the other megatooth sharks were genuinely enormous carnivores that ate other predators, and meg went extinct only a few million years ago."
Megalodon fossils are no longer available since shark bones are constructed of cartilage, thus the only way to try to piece together a picture of these animals and how they lived is through their teeth. Sharks create hundreds of teeth during their lifespan as they mature, which is fortunate for paleontologists.
Very little pieces of organic material that are embedded in the enamel of the teeth provide researchers with the nitrogen values. Measurements may be made using dental drills, cleaning agents, and bacteria that turn nitrogen into nitrous oxide.
In addition to a specially designed nitrous oxide extraction apparatus, the study called for a thorough analysis of nitrogen measurements made from contemporary marine species to enable the scientists put their megalodon findings into some sort of perspective.
Scientists refer to the trophic levels as the layers of the food chain, and marine food webs can be more complex than the classic plant, herbivore, and predator system, particularly when the marine ones begin with tiny species (phytoplankton, rather than large plants).
This megalodon and other enormous prehistoric sharks' tooth research indicates that there were more trophic tiers at the top as well.
"If megalodon existed in the modern ocean, it would thoroughly change humans' interaction with the marine environment," states Danny Sigman, a geoscientist from Princeton University in New Jersey.
According to the experts, the enormous shark would have consumed every kind of predator, even predators of predators. Although it's difficult to be certain, they most likely consumed whales and maybe even other megalodons for food.
You may be aware of the magnitude of these sharks if you've watched the 2018 film The Meg. Why such a dominant predator became extinct is an open topic, and it is thought that perhaps another species of shark finally outcompeted the megalodon.
The scientists examined both previously obtained samples and teeth that were recovered from the ocean floor for this investigation. The researchers' chemical analysis technique will next be used to teeth from other creatures, such as mammals and dinosaurs, in the future.
"Our tool has the potential to decode ancient food webs," according to Kast. "What we need now is samples... we could do the same nitrogen isotope analysis and put together the whole story of an ancient ecosystem."
The research has been published in Science Advances.
