Associated Press reports: [edited]
The idea of taking apart a rat's heart and transforming it into a tissue-engineered stingray first came to Kevin Kit Parker during a trip to the New England Aquarium with his daughter. Four years later, a robotic ray that swims toward light has made the cover of Science Magazine and is pushing the limits of what's possible in the design of machines powered by living cells.
It's remote-controlled, guided by a blinking blue flashlight. Each burst of blue sets off a cascade of signals through the cells, which have been genetically-engineered to respond to light. The contraction of the tissue creates a downward motion on the ray's body. When the tissue relaxes, the gold skeleton recoils — moving the fin upward again in an undulating cycle that mimics the graceful swimming of a real ray or skate.