While scientists had long thought that sharks may be the closest thing to ‘living fossils,’ it turns out that the modern shark is more evolved from its ancestors than previously though, according to new research.
U.S. researchers looked at 325 million-year-old fossils that were found in the Ozarks in Arkansas and published their findings in Nature. According to The Guardian, the researches said that the fossils are of a shark ancestor that was only a meter long and had tiny teeth. It is the earliest example of a chondrichthyans, the group that includes sharks.
The fossil has been named Ozarcus mapesae is honor of the Ozarks, reports Discovery News. Lead author Alan Pradel said that it is evidence that sharks “have probably more than 420 million years of evolution behind them!”
The ancient shark had more in common with fish than sharks and suggests that fish evolved gill structures before sharks. That contradicts a long-held belief among scientists that sharks developed gill structures 400 million years ago, before dinosaurs walked the earth.
The researchers also believe that the findings can help us understand evolution outside just sharks. “The findings suggest that bony fishes may provide more clues about our first jawed ancestors than modern sharks,” the paper states.