Toggle caption Photo by Neither of these reptiles is a snake. BIODIVERSITY HERITAGE LIBRARY

How a Fossilized Snake With Legs Fits Into the Lineage of Lizards

“Snakes are just fancy lizards,” says one evolutionary biologist.

LAST MONTH, FOLLOWERS OF SCIENTIFIC news were agog to look at a newly excavated and pristine fossilized skull, which came from a Mesozoic snake with legs. This discovery presumably gave many readers pause. Um, what even is a snake with legs? Is that like a worm with wings? According to scientists, the discovery will help solve the mystery of when snakes evolved into their modern form. According to everyone else, the discovery deepened the mystery of whether a snake with legs can still be called a snake.

Sara Ruane, a herpetologist and evolutionary biologist at Rutgers University who studies living snakes, has some answers. “Snakes are just fancy lizards,” she says. More precisely, she explains, snakes represent a distinct branch of the lizard evolutionary tree. Both types of animals are squamates, the largest order of reptiles, and snakes belong to the suborder Serpentes. In other words, all snakes are technically lizards, but not all lizards are snakes.

It’s also true, Ruane says, that early species of snake once sported gams. But all these legged snakes are extinct today, meaning that you’d be unlikely to confuse a snake for a lizard in the wild.

Read the whole article on Atlas Obscura