Snake or lizard? In Scotland, researchers have discovered a 167 million year old fossil with an extraordinary combination of characteristics. Pine and teeth are reminiscent of today’s snakes, while the body resembles that of a lizard. The find raises new questions about the evolution of the snakes. Is it an original snake with legs? Or has an extinct group of lizards developed a snake -like bit separately?
Lizards and snakes are both among the scale creepers, also called squamats, but are only related to each other. Her last joint ancestors lived around 190 million years ago. Again and again paleontologists came across snake -like jawbones in the immediate vicinity of bones with gecko -like characteristics. However, since the fossils were not complete and seemed to differ too differently, some researchers assumed that they belonged to two different types of animal. Others set the thesis that it was a group of predatory scale crawl animals called Parviraptoridae.
Mosaic from characteristics
A new fossil now brings light into the dark: As early as March 2015, a team around Roger Benson from the American Museum of Natural History in New York discovered a 167 million year old, largely fossil lizard at excavations on the Scottish Isle of Skye, which has both features of snakes and lizards. After ten years of detailed studies, the researchers have now published their results. They gave the newly discovered species the name Breugnathair Elgolensis borrowed from the Gaelic, which means “wrong snake by Elgol”. Elgol is the Scottish village, near whom the fossil was found.
“Snakes are remarkable animals that have developed according to previous knowledge of lizard -like ancestors with long, limited bodies,” says Benson. “Breugnathair has snake -like teeth and pine, but is surprisingly primitive in other ways.” The hook -shaped -bent teeth are similar to those of today’s pythons and the pine is also structured in a snake. The shape of the head, on the other hand, is more reminiscent of a waran and the body has large, clearly pronounced limbs, as they are typical of primeval geckos.
Snake ancestor or primal ligament?
Although the bones were disorganized at their find, according to the researchers, they fit together so well that they can clearly be assigned to a single individual. The fossil thus proves that snake and lizard-like features can really appear in the same animal and that the Parviraptoridae were actually an independent animal group. With a body length of around 40 centimeters, Breugnathair was one of the largest lizards of the ecosystem at that time and probably fed on smaller lizards, early mammals and young dinosaurs. The growth rings on the bones suggest that the individual found was at least nine years old.
But the discovery also raises new questions: “The mosaic of characteristics could either indicate that the ancestors of the snakes were very different than we expected,” explains Benson. “Or it is an indication that snake -like predate strategies have developed separately in a primitive, extinct group.” The researchers cannot answer whether Breugnathair was an original ancestor of the snakes, or whether the snake -like jaw developed in a group of squamates independent of the snakes, based on the previous finds. “The fossil brings us quite far, but it doesn’t bring us all the way,” says Benson. “But it makes us even more curious about the opportunity to find out where snakes come from.”
Source: Roger Benson (American Museum of Natural History, New York, USA) et al., Nature, DOI: 10.1038/S41586-025-09566-Y