New skulls and skeletons of the Cretaceous legged snake Najash, and the evolution of the modern snake body plan
© Elaine W Zhao/Getty
Snakes may have wandered about on legs for 70 million years before becoming the slithering serpents we see today.
Our understanding of how snakes evolved their long, legless bodies and highly mobile skulls is limited due to huge gaps in the fossil record.
A team that included researchers from Flinders University in South Australia used computed tomography scans to study the shape of eight well-preserved skulls of legged snakes recently discovered in northern Patagonia, Argentina.
The skull morphology is most similar to that of the ancient legged snake, Najash, but retains several lizard-like features alongside the emergence of adaptations to the jaw bones that enable snakes to swallow enormous snacks whole. The age of these fossils and those of other limbed snakes suggest that serpents sauntered about from 170 to 100 million years ago.
- Science Advances 5, eaax5883 (2019). doi: 10.1126/sciadv.aax5833