Other MIT engineers have designed robotic turtles and even a robotic fish, dubbed RoboTuna.

CNN: Snails inspire design for state-of-the-art robots

He said the robotic fish, which took three years to create, could also be used in the ocean.

CNN: Robotic fish make aquarium debut

Malcolm MacIver and colleagues at Northwestern University have created an "artificial electric-field sensing system that could ultimately give robotic subs the same additional sensory capabilities" as found in weakly electric fish.

ENGADGET: Robotic submersibles take on fish-like sensing abilities