Recently, the China Biodiversity Conservation and Green Development Foundation (referred to as China Green Development Association, Green Society) found a new study published online by an internationally renowned journal (PHYS.org) on the official website of the CBD: the discovery of an ancient salamander hidden in mysterious rocks for 50 years. The Green Society International Department has compiled this article as follows for the reference of interested readers.
（Marmorerpeton Brennan Stokkermans. Credit: Author）
In the fairytale landscape of the Isle of Skye on Scotland's northwest coast, the skull of one of the oldest salamanders ever found has been excavated from the limestone of the Jurassic period. But it will be decades before scientists have the technology and money to stitch the salamander together.
Part of the skeleton was collected in the early 70s of the 20th century, when paleontologists Michael Waldman and Robert Savage noticed black bones exposed on the hard gray rock surface, suggesting that a fossil was locked inside. They collected it and realized it might be something important. Although part of the fossil was later exposed, it was too small to warrant detailed study. As a result, the fossil remains in the rock and has not been studied for 45 years.
Field visits to the site began in 2004 and a number of fossils, including salamanders, were found. Roger Benson examines lumps collected in the 1970s. He realized that the shattered surface matched a specimen he collected in 2016.
Most bones collected during field trips are not immediately studied. Getting funding for field trips is difficult, but it's even harder to get funding to study the fossils you collect. It is not uncommon for them to be shelved for decades and not studied.
X-ray micro-CT scans revealed the remains of a new fossil species of salamander on the rock: Mamorerpeton wakei. At 166 million years old, it is one of the oldest known salamanders, and it records one of the earliest known stages of their evolution.
Salamander fossils are rare. Throughout the Jurassic period (2.01-145 million years ago), fewer than 20 species were discovered. By comparison, we know that there are more than 450 dinosaur species. Salamanders are harder to find because they are small and delicate – but this lack of knowledge may also be due to a lack of scientific attention.
Finally recognized: paleontologists had the first glimmer of evidence about an extinct salamander species 30 years ago, when partial fossilized backbones and mandibles were found near Oxford, England. However, it has been largely ignored by the scientific community in favor of research on the salamander (Karaurus) from Kazakhstan during the Middle Jurassic period. Until now, Karaurus is often regarded as the common ancestor of modern salamanders.
The skeleton of the Mamorerpeton fossil is still preserved inside the hard rock. Before we used X-ray micro-CT scans, we weren't sure what was inside. Most lumps are collected without knowing exactly what is inside. A fossil block recovered in 2016 was found to be the other half of a specimen taken from the same place more than 40 years ago.
Most of the skeleton has been preserved, including the skull and tail. Turning bones into digital models was hard work, but it allowed us to make a three-dimensional model of a (uncrushed) skull, unprecedented for fossil salamanders.
Typically, fossils are collected during field trips, but have not been studied for many years due to lack of time or expertise. In the case of the 1971 specimen, the edges of some bones are visible, but it is very difficult to remove these bones. Mechanical removal can damage them, but X-ray micro-CT scans allow us to see the bones clearly.
Our new analysis places the new species, Marmorerpeton, in the extinct genus Karauridae. Members of this group all have crocodile-like decorated skulls and bony bumps behind the eyes. The new species is named after the late Professor David Wake, an American authority on salamander evolution.
The wide skull, deep tail, and unfinished limb bones at the ends suggest that Marmorerpeton had an aquatic lifestyle, similar to the living ceramander (Cryptobranchus) of North America and the giant salamander (Andrias) of China and Japan. They may prey on insects by sucking and lay eggs, fertilizing them externally.
Salamanders are generally either aquatic, (as in Siren), terrestrial (as in Plethodon), or aquatic at first and become terrestrial (as in Triturus) as adults. It is possible that the earliest salamanders were aquatic, but not enough fossils have been found to be sure.
Our study shakes what scientists think they know about the evolution of giant salamanders. Our analysis shows that several fossils from the Chinese Jurassic and Cretaceous (such as Chunerpeton), once thought to be early members of the modern giant salamander group, are not closely related to living giant salamanders. Previous studies have relied too much on Karaurus (Archaeopteryx in salamanders) from the Late Jurassic of Kazakhstan.
Salamanders are essential to science. Scientists have studied salamanders for clues to understand bone development, limb and organ regeneration, and toxicology in all vertebrates, but little is known about salamanders themselves. Many people think of salamanders as a species of lizard and are unaware of their diversity.
Today there are more than 750 species of salamanders distributed on the northern continent. There are eel-like forms that live in flooded burrows, herbivores with beaks that swim, and small terrestrial salamanders that climb trees with their tails or catch prey with chameleon-like tongues. Some species exhibit parental care, such as nesting and nesting.
There are three species of salamanders in the UK. They all live in water as larvae (salamanders) and are terrestrial-based in adulthood. They return to the water to breed. Salamanders are important for food webs. Many of them eat a variety of insects, and they are prey for many animals and even some plants. Unfortunately, many species are threatened by habitat loss.
The Middle Jurassic fossil source on the Isle of Skye is of global importance. Fossils of lizard-like reptiles, early lizards, crocodylomorphs, turtles, pterosaursaurs, mammals and long-necked dinosaurs have all been found here. (Translation/Maggie)
Original:
https://phys.org/news/2022-07-ancient-salamander-hidden-mystery-yearsnew.html