Mislabelled fossils shows snakes much older

A re-examination of four fossils reveals the origins of snakes go back almost 70 years earlier than previously thought, according to a new study.

The fossils were originally labelled as lizard specimens. A decade ago, University of Alberta Professor Michael Caldwell was in London, England with a graduate student who was studying them.

Fossils were misidentified

“As I was going through the specimens with him really looking at them closely for the very first time, I realized that some of them had been misidentified, and that they were in fact not lizards but were snakes,” says Caldwell. This became clear because snakes have very distinctive head, with jaws that can slide to accommodate very big prey.

ListenThe fossils were between 140 and 167 million years old, which means these creatures, lived at the time of the dinosaurs. The study of them suggests the characteristic snake skull evolved long before snakes lost their legs and changes the thinking on how snakes evolved.

‘Gap’ in the fossil record

It also indicates there is a gap in the fossil record and that researchers need to look for more fossils to try to discover more about snake evolution.

“We’ve got to look in older units of rock and probably significantly older and our search image should probably extend to a body that looks a lot more like a lizard, in other words an animal with four legs, because snakes are descended from lizards for sure,” says Caldwell.

“We’ve got to look for something that’s got less of a snake skull and looks a great deal more like a lizard and that’s more like 210 to 220 million-year-old rocks.”