15 Million Years before the Megalodon, This Giant Ancient Shark Prowled the Oceans

"Before the famously huge megalodon, another fearsome ocean predator roamed the seas. According to a paper published earlier this year in Communications Biology, a massive shark that exceeded the size of modern-day great whites prowled the water off what is now Australia 15 million years before the megalodon arose. By analyzing a set of five vertebrae found on an Australian beach, paleontologists estimated that this ancient shark likely spanned about eight meters in lengthfor comparison, great white sharks tend to grow to around six meters today."

"It would've looked for all the world like a modern, gigantic shark, because this is the beauty of it, said Benjamin Kear, a senior curator at the Swedish Museum of Natural History and a study co-author, to the Associated Press. This is a body model that has worked for 115 million years, like an evolutionary success story."

"Although sharks have a 450-million-year-long history on Earth, the ancestors of modern great whites don't show up in the fossil record until 135 million years ago. And crucially, these ancestors were typically small fryjust a meter or so in length. Older discoveries had suggested that truly giant sharks such as megalodons (which could reach 17 meters) evolved around 100 million years ago. But the new analysis suggests that giant sharks came on the scene earlier than previously thought."

Five vertebrae found on an Australian beach were analyzed and used to estimate an ancient shark's length at about eight meters. That size exceeds modern great white averages of around six meters and predates the megalodon by roughly 15 million years. The shark likely resembled a modern giant shark, reflecting a body plan that persisted for about 115 million years. Sharks have a 450-million-year history, and ancestors of modern great whites appear in the fossil record around 135 million years ago and were typically about one meter long. New evidence indicates giant sharks emerged earlier than previously thought. Further searches for ancient giant shark remains are planned to clarify shark evolutionary history.

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