The world's oldest lizard

ICTP researcher Federico Bernardini, in collaboration with an international team, have identified the world’s oldest lizard, providing key insight into the evolution of modern lizards and snakes. Their research appears on the cover of the 30 May issue of Nature.

The 240-million-year-old fossil, Megachirella wachtleri, was originally found 20 years ago in the Dolomite Mountains, a UNESCO World Heritage Site in Northern Italy. Researchers originally thought it was linked to—but not an ancestor of—modern lizards and snakes. Further analysis by an international team of researchers determined the specimen was actually the oldest relative ever found of all living lizards and snakes, shaking up the evolutionary family tree of reptiles and shedding new light on the survivors of the most devastating mass extinction the world ever faced.

An analysis of the fossil and data from both living and extinct reptiles—including anatomical data drawn from CT scans and DNA—suggests the origin of the species we see today may be older than expected.

The fossil was recently analysed using the most advanced technologies, including high-resolution computer tomography, at the ICTP Multidisciplinary Lab and Elettra synchrotron facility in Trieste. The three-dimensional digital images obtained allowed the researchers to look through the rock, at parts of the skeleton that were previously inaccessible, without damaging this unique fossil by removing the embedding rock mechanically. This revealed a whole new suite of anatomical features that place Megachirella in a different and much more interesting light, revealing that it was actually older than previously estimated, by at least 10 million years.

Watch this video by MUSE – Science Museum, Trento – Italy, in which the authors talk about the significance of the discovery and take us behind the scenes of the research project.

Original paper

“The origin of squamates revealed by a Middle Triassic lizard from the Italian Alps” doi.org/10.1038/s41586-018-0093-3

To read more

https://www.theguardian.com/science/2018/may/30/worlds-oldest-lizard-fo…

http://www.abc.net.au/news/science/2018-05-31/megachirella-wachtleri-fo…

https://www.livescience.com/62693-mother-of-lizards-fossil.html