A group of European researchers has developed a spinal cord model of the salamander and implemented it in a novel amphibious salamander-like robot. The robot changes its speed and gait in response to simple electrical signals, suggesting that the distributed neural system in the spinal cord holds the key to vertebrates’ complex locomotor capabilities.

In a paper appearing in the March 9, 2007 issue of the journal Science, scientists from the EPFL in Switzerland and the INSERM research center/University of Bordeaux in France introduce their robot, Salamandra Robotica. This four-legged yellow creature reveals a great deal about the evolution of vertebrate locomotion. It’s also a vivid demonstration that robots can be used to test and verify biological concepts, and that very often nature herself offers ideal solutions for robotics design.

The researchers used a numerical model of the salamander’s spinal cord to explore three fundamental issues related to this vertebrate’s movement: what were the changes in the spinal cord that made it possible to evolve from aquatic to terrestrial locomotion? How are the limb and axial movements coordinated? And how is a simple electrical signal from the brain stem translated by the spinal cord into a change in gait?