 The traditional view of hammerhead shark evolution is that species with smaller cephalofoils evolved first from a requiem shark ancestor, and later gave rise to species with larger cephalofoils.Under this interpretation, the winghead shark is the most derived hammerhead, as it has the most extreme cephalofoil morphology.However, molecular phylogenetic research based on isozymes, mitochondrial DNA, and nuclear DNA have found the opposite pattern, with the winghead shark as the most basal member of the hammerhead family.