Sydney: A long-extinct prehistoric fish had the sharpest teeth that have ever been recorded, even though they were only a millimetre in size.
Scientists from Monash and Bristol Universities showed the teeth of Conodonts, a group that first appeared around 500 million years ago, were easily able to bite through their food despite their tiny size.
The fragile nature of the tiny fossil remains of animals that died out more than 200 million years ago meant scientists had to create virtual 3D models using X-rays from a particle accelerator in Japan before they could conduct thorough research, the journal Proceedings of the Royal Society B reports.
Study co-author Alistair Evans, from Monash School of Biological Sciences, said evidence suggested the Conodonts were the first vertebrates to develop teeth.
"Conodonts had no other skeleton than the teeth in their mouths. These came together a bit like scissors, to slice up food," Evans said, according to a Monash statement.
"The Conodonts took an alternative route through evolution to humans, who developed less efficient, but less breakable, blunter teeth, to which greater force can be applied by jaw muscles," Evans said.
"The sharpness of Conodont teeth allowed them to overcome the limitations of their small size. Since pressure is simply force applied divided by area, to increase pressure you must either increase the force or shrink the area. Conodont evolution took the latter route, allowing them to apply enough pressure to break up their food," said Evans.