Fossil discovery in storage room cupboard shifts origin of modern lizard to 35 million years – ScienceDaily

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A specimen recovered from the treasury of the Natural History Museum in London has shown that modern lizards originated in the late Triassic period and not the middle Jurassic period as previously thought.

These fossilized relatives of living lizards such as monitor lizards, gila monsters and slow worms have been identified in a stored museum collection from the 1950s, including specimens from a quarry near Tortworth in Gloucestershire, southwest England. Technology did not exist at the time to expose its contemporary features.

As a modern type lizard, the new fossil affects all estimates of the origin of lizards and snakes, which are together called Squamata, and influences assumptions about their rates of evolution, and even the main catalyst for the group’s ancestry.

The team, led by Dr David Whiteside of the School of Geosciences in Bristol, named their discovery astonishing Microlanius cryptophranoids It means “little butcher” in honor of its jaws filled with sharp, cutting teeth.

Dr Whiteside explained: “I first spotted the specimen in a cupboard full Clevosaurus Fossils in storage at the Natural History Museum, London, where I am a scientific fellow. Common enough, this fossil reptile was a close relative of the New Zealand tuatara and is the sole survivor of the group, Rhynchocephal, which broke off from the nymphs more than 240 million years ago.

Our sample was simply classified.Clevosaurus and other reptiles. As we continued to investigate the specimen, we became more and more convinced that it was in fact more closely related to modern lizards than the Tuatara group.

“We did an X-ray scan of the fossils at the university, and this enabled us to reconstruct the fossil in three dimensions, and to see all the fine bones that were hidden within the rock.”

Cryptopharanoids It is clearly chiral in that it differs from Rhynchocephal in the brain, in the neck vertebrae, in the shoulder region, in the presence of a middle upper tooth at the front of the mouth, the way the teeth are set on a shelf in the jaws (rather than fused into the apex of the jaws) and in the structure of Skull like no lower temporal bar. There is only one major primitive feature not found in modern husks, and that is an opening on one side of the end of the humerus, the humerus, through which the artery and nerve pass. Cryptopharanoids It has some other, apparently rudimentary, characters, such as a few rows of teeth on the bones of the roof of the mouth, but experts have observed the same in the living European glass lizard and many snakes such as Boas and Pythons have multiple rows of large teeth in the same area. Despite this, it is as advanced as most living lizards in its brain and the bony connections in its skull indicate that it was flexible.

“In terms of significance, our fossils alter the origin and diversification of scutes from the Middle Jurassic to the Late Triassic,” says co-author Professor Mike Benton. “This was a time of great restructuring of the ecosystems on Earth, with the origins of new plant groups, especially modern conifers, as well as new species of insects, and some of the first groups of modern groups such as turtles, crocodiles, dinosaurs, and mammals.

Adding the oldest modern squats then completes the picture. These new plants and animals seem to have come onto the scene as part of a major reconstruction of life on Earth after the mass extinction at the end of the Permian period 252 million years ago, especially the Pleiobian Carnivorous ring, 232 million years ago when it was Climates oscillated between wet and dry and caused great disruption to life.”

PhD student Sophia Chambi-Trowell commented: “The new animal’s name, Microlanius cryptophranoidsAnd the It reflects the hidden nature of the Beast in the Drawer but also its unlikely lifestyle, living in crevices in the limestone on small islands that existed around Bristol at the time. The species name, meaning “little butcher,” refers to its jaws, which were filled with sharp-edged cutting teeth and would have fed on arthropods and small vertebrates.

Dr Whiteside concluded: ‘This is a very special fossil and is likely to become one of the most important fossils found in the last few decades. It is fortunate that it is being kept in a national collection, in this case the Natural History Museum, London. I would like to thank The late Pamela L. Robinson who recovered the fossils from the quarry and did much preparatory work on the type specimen and associated bones. It was unfortunate that she did not have access to tomography technology to help her observe all the details of the specimen.”

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