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To study the transition from aquatic to terrestrial locomotion, Ijspeert et al. took a cue from the motion of the salamander (clip 1) -- the tetrapod that most closely resembles the first terrestrial vertebrates -- to develop a robotic spinal cord model (clip 2). With a mere change in signal strength, the robot can swim to shore, crawl onto land, and walk away. The model could help scientists infer what types of evolutionary changes were needed to allow for rapid switching between swimming and walking. This model builds off of vertebrates’ central pattern generators (CPG), and suggests neural mechanisms for modulating velocity, direction, and type of gait that are relevant to all four-limbed vertebrates, including humans.