Fishy tale of how we got our teeth
Teeth grew from the scales of primitive shark-like fish, new evidence has shown.
Old lineage cartilaginous fish, such as sharks, skates and rays, lack bony skeletons and have skin containing small spiky scales called "dermal denticles". Their tooth-like appearance is no accident, scientists believe.
During the early evolution of jawed vertebrates, evolution transferred dermal denticles from the skins of primitive fish to the mouth. In the millennia that followed, the tiny appendages went on to produce the six-inch long teeth of dinosaur Tyrannosaurus rex and the formidable fangs of the sabre-toothed cat. Our teeth could represent a direct link between us and our distant fishy ancestors.
Lead scientist Dr Andrews Gillis, from Cambridge University, said: "Our findings suggest a deep evolutionary relationship between these primitive fish scales and the teeth of vertebrates."