(CNN) — A 280-million-year-old fossil is believed to be the best-preserved specimen of an ancient reptile, according to new research.
Originally discovered in the Italian Alps in 1931, the fossil bears the scientific name Tridentinosaurus antiguus. Scientists thought the deep, dark exterior of the lizard-like body in the rock was skin and soft tissue, and considered the fossil a puzzle piece in understanding the early evolution of reptiles.
The fossil has appeared in references in books and articles for decades, but no one has studied it in detail. The specimen, housed in the collection of the Museum of Nature and Humanities at the University of Padua in Italy, raised many questions about the exact identity of the living creature when no further similar specimens were found.
A detailed new analysis revealed that the fossil's dark color wasn't preserved genetic material: it was black paint covering a pair of bones and carved rocks. The researchers behind the study reported their findings on February 15 Journal of Paleontology .
“The body shape of this fossil specimen has the same color as the actual fossilized soft tissues of plants and animals,” the study's lead author, Dr. Valentina Rossi, a postdoctoral researcher in paleobiology at the University of California, San Francisco, said in an email. Cork College in Ireland. “Therefore, it is impossible to correctly identify a dark-colored object without using detection techniques.”
This presentation highlights the new insights that can be gained by re-examining ancient and previously studied fossil specimens in museum collections using the latest technological methods.
Finding a fake
Reptiles first appeared between 310 and 320 million years ago between the Carboniferous and Permian periods. But understanding the evolution of these scaly vertebrates depends on what paleontologists find in the fossil record, and the diversity of early reptiles remains a knowledge gap researchers are trying to fill.
The rarest of ancient finds are fossils containing soft tissue, which has the potential to hold important biological information such as DNA.
When the specimen was discovered, researchers thought the fossil could provide a rare glimpse into the evolution of reptiles.
“The fossil was believed to be unique because there were no other examples from the same geographic region and geological period preserved in a fossilized vertebra at the time,” Rossi said.
But the color of the skin is similar to that found in fossilized plants found in similar rocks, Rossi said.
Although the body did not appear to be completely flat, there were oddities in the find, such as the absence of normally visible bones, including the cranial bones. Therefore, the initial assessment is that this specimen is an ancient reptilian mummy.
“One plausible explanation is that the bones are hidden under a layer of skin, so they are not visible,” Rossi said. “There are some examples Dinosaur mummiesThere, like human mummies, the bones are still wrapped in skin that is preserved in 3D.”
Motivated by the growing uncertainty surrounding the fossil, Rossi and his colleagues began their study in 2021 with ultraviolet photography. Analysis revealed that the sample was covered in a thick layer, Rossi said.
“Varnishing fossils is an ancient preservation method because, in the past, there were no other suitable methods to protect them from natural decay,” said study co-author Mariagabriella Fornaciero, curator of paleontology at the Museum of Nature and Natural History. Humanities, in a statement.
In hopes of uncovering biological information about the fossil beneath the coating, the team used powerful microscopes to examine samples of the remains at different wavelengths of light.
Instead, the researchers determined that the body's exterior was carved into rock and painted with “animal charcoal,” a commercial pigment used more than 100 years ago by burning animal bones. The carving also explains why the specimen appears to have retained such a realistic shape, instead of appearing flattened like a real fossil.
“We have the answer to all our questions right in front of us, and we had to study this fossil specimen in detail to reveal its secrets, even the ones we didn't want to know,” Rossi said.
The result was unexpected, but explains why the fossil has puzzled researchers for decades. “The latest research confirms that this is not the oldest mummy in the world,” study co-author Evelyn Gustadscher, curator of paleontology and project coordinator at the South Tyrolean Nature Museum in Bolzano, Italy, said in a statement.
Old secrets and new questions
Interestingly, there are actual bones inside the fossil. The hind legs, although in poor condition, are real and have traces of osteoderms or scales-like structures. Now, researchers are trying to determine the exact age of the bones and what animal they belong to. The team is also studying rock that reveals details dating back 280 million years.
This isn't the first time a fossil fake has been found, but Rossi said this particular style of fake is unusual.
“The only fossil I know of is a fossilized crab that was painted on rock, and it looked like a giant spider,” Rossi said. “However, in this particular case, the type of paint was not identified, but I'm betting it was a carbon-based paint similar to what we found in our fossil.”
Due to the lack of records accompanying the fossil, including a description of what exactly was found in 1931, Rossi and his team cannot fully confirm that this forgery was intentional.
“Because some of the bones are visible, we think someone tried to expose the skeleton and dug up the rest of the animal roughly where you'd expect it,” Rossi said. “Not having the right tools to prepare the hard rock didn't help, and eventually applying paint was just a way to beautify the final work. “Unfortunately, all of this, whether intentional or not, has misled many experts into interpreting this exceptionally well-preserved fossil.”
Using advanced techniques to study fossils can reveal their true nature, Rossi said.
“It is of fundamental importance that research uses new methods to closely observe findings that have already been studied,” said study co-author Fabrizio Nestola, professor of mineralogy at the University of Padua and head of the university's museum center. , in a statement.
“Tridentinus is an example of how science uncovers old secrets and how new questions arise from them,” Nestola added. “The mission of our museum will then be to process the new knowledge gained and bring it closer to the public to conduct a scientific and cultural debate.”
