Researchers discovered the skull of this 90 million-year-old biblical snake Najash at the La Buitrera deposit, northwest of Río Negro (Argentina).
Since 2006, only his body was known and he had four legs, as was the beast of the Bible that was condemned by God to crawl after deceiving the first couple according to the Hebrew tradition.
Najash rionegrina is an ancient snake less than two meters long, which had well-developed legs that would have been useful to move or, perhaps, to anchor against the ground when attacking. The new finding of his face illuminates unknown aspects of the evolution of the snake skull.
Dr. Sebastaían Apesteguía, a researcher at the Felix Azara Foundation (Maimonides University) and CONICET, told the CTyS-UNLaM Agency that the first fossils in Najash were found in 2001, but the skull had never been found.
Najash was a headless snake. Until, in the 2013 expedition, the expected discovery occurred. «That year, a student of Biological Sciences from the University of Buenos Aires (UBA), Fernando Garberoglio, accompanied us on the expedition, and he found an incredible fossil when he raised a small stone; He had Najash’s full skull with his whole face, with the eye orbits, and including some neck vertebrae, ”Apesteguía said.
“The detailed study of Najash’s face is essential to understand the evolution of snakes not only in South America but throughout the world,” said the paleontologist. He said: “It is not the oldest snake, because now we know there was from the upper Jurassic, but it is undoubtedly the most complete and best-preserved.”
A smile in three dimensions
The famous smile of the Mona Lisa is observable in two dimensions. But the same could not be done with the approximately 100 million-year-old fossils that were known from the snakes of the Middle East.
According to Apesteguía, «the snakes of the Middle East are of marine environments and their preservation is two-dimensional, that is, they are preserved as if it were a photocopy of the fossil, while those of South America, especially Najash de La Buitrera, are conserved three-dimensionally , so we can grab each bony and analyze it on all its sides ».
And just as the Mona Lisa, they say, has a mysterious smile, the smile of the ancient snakes kept a very big mystery for experts in these fossil animals until the discovery of Najash’s skull.
“The snakes of the Middle East are complete in two dimensions from the head to the tip of the tail, but, with the discovery of Najash’s face, we can analyze a cheekbone bone that appears for the first time,” said the paleontologist. And he added: “It was a very discussed bone because in the two-dimensional fossils it was not understood what bone it was.”
Regarding the mouth and the opening of the mouth, Dr. Apesteguía said that this new fossil «allows us to understand part of the cranial characters that are common in today’s snakes so that they can open their mouths larger than their head, whether to eat an egg or an animal much larger than its body, for example ».
“This could not be done by the old snakes, they could not open their mouths in such a way, but they did have the beginnings of those characteristics,” Apesteguía observed to the Agency CTyS-UNLaM.
The expert specified that Najash rionegrina «had several points of the skull where a bone, instead of being locked with another bone, interacted in a mobile way, what is called cranial kineticism; then, they could open their mouths to make them big, but not larger than their own head.
These ancient snakes could not eat large prey and were not poisonous either. «Surely, they fed on small lizards, sphenodes, or perhaps some small mammal; in no way could they eat dinosaurs, but, on the contrary, many local dinosaurs, such as the Buitreraptor, surely predated these snakes among other animals.
La Buitera, an amazing site
Since 1999, the Vulture has provided an impressive list of completely new finds, such as the Buitreraptor and Alnashetri dinosaurs, the sphenedon reptiles ( Priosphenodon ), mammals such as the famous Cronopio ( similar to the squirrel of the Ice Age movie ), turtles and fish
This investigation by Najash was subsidized by CONICET and the National Geografic Society , while expeditions to La Buitrera were made through an agreement with the Government Culture Agency of the Province of Río Negro.
The study – of which Michael Caldwell of the University of Alberta also participated – was published in the journal Science Advances.
Source: CTyS-UNLaM Agency