Unexpected step: Snake ancestor had four feet

The oldest snake fossil on record looks almost like a modern snake, except for one glaring difference: It has four feet, each with five digits, a new study finds. The roughly 120-million-year-old snake, dubbed Tetrapodophis amplectus (meaning four-legged snake), likely didn’t use its feet for walking. Instead, the appendages may have helped Tetrapodophis hold onto a partner while mating, or even grip unruly prey, said study co-researcher David Martill, a professor of paleobiology at the University of Portsmouth in the United Kingdom.

We’ve found the ancestor of all snakes. We have found the missing link between four-legged lizards and snakes.

study co-researcher David Martill told Live Science

Previous research has detailed two-legged snake fossils, but this is the first known snake ancestor to sport four legs, he said. It likely evolved from terrestrial-burrowing creatures, and was a transitional animal that lived during the shift from ancient lizards to modern-day snakes, he added.

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