The tiny teeth of a long-extinct vertebrate — with tips only two micrometres across: one twentieth the width of a human hair — are the sharpest dental structures ever measured, new research from the University of Bristol and Monash University, Australia has found.
For 300 million years, Earth’s oceans teemed with conodonts — early vertebrates that kept their skeleton in their mouth. The elements of this skeleton look uncannily like teeth (see image) and, like teeth, they were often worn and broken during life. This evidence strongly suggests that conodonts evolved the first vertebrate dentitions.
Scientists know that conodont elements worked differently from the teeth of other animals: they are microscopic — about 2 to 0.2 mm long — and must have had paltry muscles to move them, with no jaws to which they could attach. So how could they possibly have worked as teeth? In a new study published March 14 in the Proceedings of the Royal Society B the Bristol and Monash University researchers answer this question.