Scientists Found a Rare Fossil Showing Snakes Once Had Legs and Looked Very Different From Today

In the past 100 million years snakes didn't look like those sleek, legless animals that we see in the present. Their ancestors were reptiles that had elongated hind legs, tougher skulls, and bodies designed to climb and crawl instead of slithering silently. The discovery of a remarkable fossil is bringing this evolution into the spotlight, and revealed how snakes evolved gradually through the loss of their legs, and altering their body shape over many millions of years.

A Discovery That Rewrote Snake History

The most significant discoveries came from a fossil that is known as Najash the rionegrina snake which lived from about between 95 and 100 million years ago in the Late Cretaceous period. The species was the subject of a large study called "New skulls and skeletons of the Cretaceous legged snake Najash, and the evolution of the modern snake body plan," which was published in Science Advances in 2019.


The study involved cooperation with researchers at The University of Chicago in the United States, whose contributions allowed the study of the fossil's anatomy more precisely. By using advanced computerized tomography scans Researchers recreated the skull in three dimensions. This revealed an intriguing mix of ancient and contemporary traits.

In contrast to modern snakes Najash was still well-developed in hindlimbs as well as a pelvic organ. The features that make it among the best instances of a species that was transitional which bridges that gap in between lizards as well as snakes.

A Skull That Tells an Evolutionary Story

What that makes Najash special isn't only its legs however, its skull. The fossils revealed the existence of a huge jugal bone. This is a characteristic that is common to lizards however it's not seen in many contemporary snakes. The bone may have helped in stabilizing the skull, and also supported muscles that were involved in eating.

The research also revealed how the quadrate bone that was located horizontally. This information is vital since it indicates that the earliest snakes already had the ability to spread their jaws and devour bigger prey. The evolutionary process would result in jaw flexibility found in modern species, such as boas and pythons.

This research shows the evolution of snakes wasn't one-time change, but was it was a gradual progression, and diverse traits emerging at different dates.

Why Snakes Lost Their Legs

The evidence of hind-limbs in Najash as well as other fossils of early snakes suggest that snakes with legs were not just an accident of evolution, but were an established and stable form. However, over time the environmental conditions likely favoured slimmer bodies.

Researchers believe that the first snakes were able to burrow underground or navigating through thick plant life. In these environments the long, flexible body with no protruding limbs could be more efficient. In the end the forelimbs were eliminated very early in the evolution of the snake, and hindlimbs remained over a longer time before finally disappearing.

This reduction in the rate of change demonstrates that the process of evolution is facilitated by small pragmatic changes, rather than massive changes.

Other Fossils That Support the Story

The evolution story becomes more convincing when Najash is examined alongside other species from the past. Fossils such as Dinilysia exhibit similar skull changes, and marine reptiles like Pachyrhachis as well as Eupodophis had small hindlimbs and suggest that snakes were able to thrive in various habitats.

A different intriguing fossil, Tetrapodophis amplectus, discovered in Brazil It appears to have been a tinier branches and a lengthy snake-like body. Though its classification isn't clear but it adds another dimension to the tale, suggesting the possibility that reduction of limbs occured in various levels and types.

Together, these fossils create a an intricate and intriguing image of the evolution of snakes, the evidence suggests that the change between lizards and snakes required many species of intermediate.

Why This Discovery Matters Today

Many people think that snakes appear to be mysterious that are perfectly at home in their surroundings. The fossils of Najash provide us with evidence the fact that their form today was the result of millions of years of evolution.

The study of evolutionary processes is more than just simply curiosity. Scientists can gain a better understanding of reptile anatomy, aids in conservation efforts, and aids in medical research specifically in relation to venom as well as physiology.

It also makes the world around us feel more at ease and understandable. If you happen to encounter a snake, it is important to remember that underneath the smooth and legless shape is a rich evolutionary past that has ancestors sporting leg bones, different skulls and completely different methods of traversing the earth.

The discovery doesn't just transform the way that scientists look at snakes. The discovery changes the way that we perceive them, turning the familiar snake into a living connection to an enigmatic and distant historical.