Sharks and humans have a common ancestor dating back 440 million years ago, according to a study published Tuesday. The new investigation of an ancient shark fossil further unravels the evolutionary history of sharks, and helps us understand our very distant and ancient origins. The study, in the Proceedings of the Royal Society B, investigated an ancient shark species called Gladbachus adentatus that was first studied in 2001, after its discovery in the late 1990s. Only one specimen of this species has been found and cutting-edge imaging technology allowed researchers to study it in extremely close detail, according to Michael Coates, the lead author and professor at University of Chicago’s organismal biology and anatomy department. read more Disclaimer: Chances are that this post was requested by an advertiser.