Researchers discover the origin of teeth
BRISTOL – The evolutionary origin of dental structures is highly debated among experts. Now, a team of international scientists has found evidence that tooth-like structures were present in the first jawed vertebrates, although it had long been assumed that teeth developed later. The new findings indicate that teeth developed alongside or shortly after jaw structures.
The researchers discovered the origin of both teeth and jaws through studying fossils of Compagopiscis, one of the first prehistoric jawed fish. They performed 3-D microscopy using synchrotron X-ray tomography microscopy and were able to visualise every tissue, cell and growth line within the fish’s jaws, allowing them to study the development of the teeth, said Dr Martin Rücklin, lead author and researcher at the University of Bristol’s School of Earth Sciences.
“This technique allowed us to obtain a perfect digital model and very detailed internal views of the fossil without destroying it,” said Prof. Marco Stampanoni of the Paul Scherrer Institute, the largest research centre for natural and engineering sciences in Switzerland.
The CT scans demonstrated that some primitive fish possessed jaws with distinct dental ossifications composed of dentine and bone, the researchers said.
In contrast to the hypothesis that teeth were absent in the first jawed vertebrates and that they captured their prey with scissor-like jaw-bones, the present study suggests that the development of tooth and jaw structures was intimately interwoven.
The research was conducted by palaeontologists from the University of Bristol in collaboration with evolution experts from the Natural History Museum in London and Curtin University in Australia and physicists from Switzerland.
The study was published online on 17 October in the Nature journal ahead of print.