The issue is if the Great White, one of the most feared predators of the sea, evolved from the huge prehistoric megladon shark or if its ancestry rests with the mako shark.
"Most scientists would probably say the Great Whites evolved from the megladon line, which existed from two million to twenty million years ago. They were huge sharks, approximately the length of a Greyhound bus and possessing teeth that were up to six inches long," explains Ciampaglio. "However, our research, which is based on analyzing fossils of several hundred shark teeth, shows that the Great White shares more similarities with the mako shark." He added that because sharks regularly replace their teeth, it is relatively easy to obtain tooth samples through fossil field work along the Atlantic seaboard.
Ciampaglio acknowledges that people seem to have a fascination with sharks. "The general public seems to like sharks, and maybe this is because they bring out the fears of our childhood, when they were perceived as scary monsters," he explained.
His interest in sharks is apparent when entering his office. The door and walls have pictures of shark teeth, and there are posted references to fossils and a geological time table.
The research scientist makes imprints of the teeth, then digitizes the picture to establish grids of different combinations that are analyzed by a sophisticated computer program. He even uses an electron microscope to view different serration designs of shark teeth.
"Our analysis of their teeth shows that Great White and mako sharks have very similar tooth growth trajectories, while those of the great white and megladon are not similar. Analysis of both the root and entire tooth
Source:Wright State University