The 240-million-year-old fossil, Megachirella wachtleri, is the most ancient ancestor of all modern lizards and snakes, known as squamates, according to researchers including those from the University of Bristol in the UK. Prior to this discovery, the earliest known squamate fossil was about 180 million years old, whereas genetic evidence suggests that the order originated more than 250 million years ago. Scientists have always been unsure of M. wachtleri's place in the reptile family tree.
"The specimen is 75 million years older than what we thought were the oldest fossil lizards in the entire world", lead author Tiago Simoes, who is a PhD student from the University of Alberta, explains in a release from the university.
"It pushes the origin of lizards back 75 million years".
One of the greatest things about the discovery of the Megachirella lizard fossil is that it proves that lizards and snakes survived the mass extinction that killed off the dinosaurs, and also that lizards came into being long before what has been called the Great Dying, as paleontologist Alessandro Palci explained.
A team of worldwide scientists published their findings in the academic journal Nature, which revolved around the chameleon-sized reptile Megachirella wachtleri. Simões concludes that the information they got from the fossil can help them understand the transition "from general reptile features to more lizard-like features".
"Fossils are our only accurate window into the ancient past", said co-author Professor Michael Caldwell, also from the University of Alberta.
Using a micro CT scanning, he was able to look inside the rock and see the whole fossil. At a synchrotron facility, Simões and his colleagues identified features in the animal's brain case, collar bone and wrists that are unique to lizards.
This handout picture received via the Nature website on May 28, 2018 shows a life scene in the Dolomites region, Northern Italy, about 240 million years ago, with Megachirella wachtleri walking through the vegetation.
"When I first saw the fossil I realised it had important features that could link it to the early evolution of lizards", he said.
"It's confirming that we are pretty much clueless".