- Snakes Lost Their Legs
Plenty of evidence shows that snakes used to have limbs, although researchers continue to debate whether today’s serpents evolved from a leggy ancestor that lived on land or at sea. Most recently, a 2015 article in Science Advances made the case for land-based burrowers. Using detailed CT scans, researchers compared 3-D virtual models of the inner ears of aquatic, surface-dwelling, and burrowing snakes, lizards, and fossilized relatives. The team found specialized structures in the fossil animals akin to the ones modern burrowers use to hear low-frequency ground vibrations made by predators and prey. The evidence suggests that snakes descended from a burrowing ancestor, and their legs regressed so they could better wriggle through the ground.
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