With teeth up to 7 inches long, the megalodon was certainly one of the largest hunters ever to exist, and possibly the largest shark ever, depending on some estimates of its size. However, little is known about them, including what killed them off some 3.6 million years ago.
According to a study by a group of scientists led by geoscientist Jeremy McCormack of the Max Planck Institute for Evolutionary Anthropology in Germany, greater and greater evidence exists suggesting that the great white shark out-competed the megalodon. Their research was published in Nature Communications on Tuesday.
Other studies have looked at other causes of the great shark’s demise, but they used zinc in the fossilized shark’s teeth to judge their diet, based on surviving isotopes of certain radioactive elements known to derive from different food sources.
What they found was that the megalodon and the great white occupied the same “trophic level,” or hierarchy in nature, during the Pliocene era, which lasted from 5.3 million years ago until 2.58 million years ago, when the Ice Age began. In other words, the two sharks competed directly with each other for resources, eating the same foods.
“We observe significant zinc differences among the Otodus [Megalodon] and Carcharodon [Great White Shark] populations implying dietary shifts throughout the Neogene in both genera," the study says.
Since the great white survived into the present and the megalodon did not, they concluded that the former was a better hunter than the latter, getting food when its rival could not, especially as climatic pressures mounted.
"The extinction of Otodus megalodon could have been caused by multiple, compounding environmental and ecological factors, including climate change and thermal limitations, the collapse of prey populations and resource competition with Carcharodon carcharias and possibly other taxa not examined here," the researchers wrote.
Calculations of the megalodon’s size vary from 34 to 67 feet in length, based on different methods of estimation, and weighing between 48 and 103 metric tons. By comparison, the great white is much smaller, with the largest measuring just 20 feet long and weighing just under 2 tons. In the modern era, this is enough to make them one of the largest predators in the seas, fearing only the larger orca whale, which has been known to hunt great whites in some situations.