Scientists: the Ancestors of lizards appeared 70 million years earlier

As part of this study, the scientists scanned a piece of fossilized skeleton of the ancient chameleon-sized reptile known as Megachirella and discovered the creature to be the ancestor of the lizard of today.

Scans of the fossilised skeleton of Megachirella revealed the chameleon-sized reptile was an ancestor of today's lizards and snakes, which belong to a group called squamates, an worldwide team wrote in the science journal Nature.

More light will be shed on snakes and lizards, both living and dead, thanks to this research.

The new dating of this Megachirella means that lizards evolved more than 75 million years before they were first thought to have existed, according to Dr. Palci.

The researchers also noted that for the first time, "orphological and molecular data are in agreement regarding early squamate evolution, with geckoes-and not iguanians-as the earliest crown clade squamates".

Enter Megachirella wachtleri, a three-inch, 240-million-year-old fossil - and an exciting new clue in this evolutionary mystery.

"It's nearly a virtual Rosetta stone", said Caldwell, also a paleontologist at the University of Alberta, "in terms of the information that it gives us on the evolution of snakes and lizards". The fossil of the Megachirella died in the Dolomites during a thunderstorm in the area. Researchers couldn't figure out what type of reptile it was and how far back it dated.

Fifteen years later, high-resolution micro CT scanning made it possible to peer inside the rock holding the fossil and identify features concealed within.

Simões saw the fossil in 2015 and worked with Michael Caldwell to create the family tree of all reptiles - extinct and living.

An artists impression of Megachirella wachtleri walking through the vegetation in the Dolomites 240m years ago. Flowers had not evolved, and the ground was dominated by primitive plants called lycopods (ancestors of club mosses and quillworts).

Simões and his colleagues are still seeking evidence of megachirella's behavior. "Megachirella is 75 million years older than the previously known oldest squamate fossils, partially filling the fossil gap in the origin of lizards, and indicates a more gradual acquisition of squamatan features in diapsid evolution than previously thought". The tiny lizard was the size of a finger and it's 250 million years old. 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".

"It's confirming that we are pretty much clueless", Simões said of the new species.

Vanessa Coleman

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