It turns out snakes are nearly twice as old as we thought. Until the publication of a new study on Wednesday, January 28th, based on the known fossil record zoologists had believed that snakes first developed around 90-100 million years ago. That has all changed, with an international team of researchers reporting the surprising discovery of four ancient snake remains ranging from 140 million to 165 million years old.
The researchers believe there are even more ancient snake remains yet remaining to be discovered.
“The study explores the idea that evolution within the group called ‘snakes’ is much more complex than previously thought,” notes Michael Caldwell, professor at the University of Alberta and lead author of the study published this week in Nature Communications. “Importantly, there is now a significant knowledge gap to be bridged by future research, as no fossils snakes are known from between 140 to 100 million years ago.”
Caldwell also commented that: “Based on the new evidence and through comparison to living legless lizards that are not snakes, the paper explores the novel idea that the evolution of the characteristic snake skull and its parts appeared long before snakes lost their legs.”
More on ancient snake fossil research
The new oldest known snake was found near Kirtlington in Southern England (Eophis underwoodi) was a fragmentary fossil remains and was a relatively small individual. The largest snake of the four (Portugalophis lignites) was recovered from coal deposits close to Guimarota in Portugal, and was around three-feet long. Three of the ancient snakes inhabited swampy coastal areas on islands in the western part of Europe. The ancient North American snake (Diablophis gilmorei) was discovered in a former riverbed in western Colorado.
This new international study is very strong evidence that the sudden appearance of snakes some 100 million years ago is a gap in the fossil record, rather than a sudden appearance and radiation of early snakes. The new evidence suggests that from 170 to 100 million years ago, snakes were speciating and evolving into the elongated, limb-reduced body shape characterizing the 100-90 million year old marine snakes found in the West Bank, Lebanon and South America that still have residual rear limbs.