Bony fish (Osteichthyes) are distinguished from other fish species that have a cartilaginous skeleton (Chondrichthyes—sharks, rays and chimaeras, for example) by the presence of true bone—a mixture of calcium phosphates and carbonates—in their skeletons. Humans and all 60,000 living species of jawed vertebrates – sharks, bony fish, amphibians, reptiles, birds and mammals – are descendants of this fish, researchers say. This indicates that bony fish and land animals retain the ancestral condition in this regard, whereas sharks are specialized in having teeth that are only attached to the skin — in contrast to the common perception that sharks are primitive living vertebrates. Credit: Boris EkrtThis diversity raises many questions about the origin of teeth. And he adds: “Even though acanthothoracids are among the most primitive of all jawed vertebrates, their teeth are in some ways far more like modern ones than arthrodire dentitions. Like arthrodires, the acanthothoracid dentitions are attached to bones. Credit: Jan SovakThe origin of our teeth goes back more than 400 million years back in time, to the period when strange armored fish first developed jaws and began to catch live prey. But the non-destructive X-rays revealed hidden details on their size and structure, showing a striking resemblance to human teeth. In addition, whilst sharks shed their worn-out teeth entire, simply by detaching them from the skin, bony fish and land animals shed theirs by dissolving away the tooth bases. All Rights Reserved. During the experiments at the ESRF, the European Synchrotron: members of the research team mounting a specimen in the experimental hutch of ESRF ID19 …
This is an important difference because it shows that acanthothoracid jaw bones were located right at the edge of the mouth, whereas arthrodire jaw bones lay further in. The fish commonly reaches 10-20 inches, but can sometimes grow to be as large as 35 inches! An international team of scientists led by Uppsala University (Sweden), in collaboration with the ESRF, the European Synchrotron (France), the brightest X-ray source, has digitally ‘dissected’, for the first time, the most primitive jawed fish fossils with teeth found near Prague more than 100 years ago. This may be evidence that the true teeth had only recently evolved from dentine elements on the skin.“These findings change our whole understanding of the origin of teeth” says co-author Per Ahlberg, professor at Uppsala University. MIT Scientists Create Giant “Artificial Atoms” to Enable Quantum Processing and Communication in OneCOVID-19 Is Disrupting Weather Forecasts – Here’s HowBest Place on Earth to See Stars – Where They Can Finally Be Seen Without Their TwinkleHow Mosquitoes Got Their Taste for Human Blood – What It Means for the FutureDiscovery of Unconventional Spin Transport in Quantum Spin Liquids May Enable Next-Generation Electronicson "Scientists Trace the Origin of Our Teeth to Primitive Fish More Than 400 Million Years Back in Time" Palaeontologists have used the European Synchrotron Radiation Facility (ESRF), the strongest X-ray source in the world, to 'digitally dissect' the primitive jawed fish.The teeth, belonging to the extinct 'acanthothoracid' fish, were discovered near Prague in the Czech Republic almost 100 years ago. At the ESRF, a 2,770-foot (844 metre) ring of electrons travelling at the speed of light emits high-powered X-ray beams that can be used to non-destructively scan matter, including fossils.