WASHINGTON (Reuters) - Scientists have created a salamander-like robot that married biology and robotics and enabled them to explore ideas about the first vertebrates that emerged from water to land hundreds of millions of years ago.

The robot, described on Thursday in the journal Science, looks and moves like a salamander and is controlled by a system that imitates the amphibian's spinal cord, enabling it to alternate between swimming and walking.

The Swiss and French scientists made the robot, named Salamandra Robotica, swim in Lake Geneva and crawl on the lake shore. They also said the robot demonstrated that biology offers good ideas for robot design.

"Nature found a nice way of making a sophisticated circuit in the spinal cord and then controlling the muscles from there," Auke Ijspeert of Ecole Polytechnique Federale de Lausanne said in a statement.

"It's a fantastic solution for coordinating multiple degrees of freedom in a simple, distributed way."

Powered by 10 motors and measuring nearly three feet (85 cm) long, the yellow robot has four rotating legs and six movable joints along its body. Simple electrical signals make it change its speed and gait.

Salamanders resemble the first vertebrates that took to land. The scientists think their robot might help shed light on how these animals first acquired walking abilities.

A salamander's gait changes dramatically based on whether it is swimming or walking, and the robot's gait changes similarly.
The designers used a numerical model of a salamander's spinal cord to examine issues related to its movement, including which changes were needed to allow a transition from aquatic to terrestrial locomotion.

Electrical signals similar to the signals sent from the upper brain to the spinal cord were transmitted from a laptop to the robot. They made the robot change its speed and direction, and change from walking to swimming.

Robots capable of changing their speed, direction and gait like living creatures could be extremely useful, for example, in search-and-rescue operations, the scientists said.