An article published in the journal “American Museum Novitates” describes a research that provides the strongest evidence yet that sharks descended from a very ancient group of fish called acanthodians. A team of researchers led by John Maisey of American Museum of Natural History’s Division of Paleontology analyzed fossil remains that were exceptionally preserved of an ancient shark-like fish called Doliodus problematicus identifying it as a transitional species between acanthodians and sharks.