On very rare occasions, an exceptional fossil is unearthed that provides an extraordinary glimpse into the evolution of a group of organisms.

This time, it is the beautifully preserved skull of an ancient snake with rear limbs, Najash rionegrina. Our study of this fossil has been published in the journal Science Advances.

This and other new fossils help answer long-standing questions on the origins of snakes, such as how they lost their limbs and evolved their highly specialized skulls.

Najash rionegrina is named after the legged biblical snake Nahash (Hebrew for snake), and the Río Negro Province in Argentina, where the fossils were discovered. Fossils of Najash are about 95 million years old, and were first described in Nature from a fragmentary skull and partial body skeleton that preserved robust rear limbs.

 

Continue reading at University of Alberta.

Image via Raúl Gómez.