As if the line between human and machine wasn't already blurry enough, researchers in Tokyo have developed a new method for using living rat muscle tissue in robotics. The "biohybrid" design, described today in the journal Science Robotics, simulates the look and movements of a human finger. Video shows how it bends at the joint, picks up a loop, and places it down. It's a seemingly simple movement but one that researchers say lays the groundwork for more advanced--and even more lifelike--robots. "If we can combine more of these muscles into a single device, we should be able to reproduce the complex muscular interplay that allows hands, arms, and other parts of the body to function," says study author Shoji Takeuchi, a mechanical engineer at the University of Tokyo. "Although this is just a preliminary result, our approach might be a great step toward the construction of a more complex biohybrid system."