This amazing biohybrid was 3D printed; it's a nickel-sized artificial stingray whose swimming is guided by light and powered by genetically engineered rat heart muscle cells.
(Biohybrid Is A Tissue-Engineered Robot)
Inspired by the relatively simple morphological blueprint provided by batoid fish such as stingrays and skates, we created a biohybrid system that enables an artificial animal—a tissue-engineered ray—to swim and phototactically follow a light cue. By patterning dissociated rat cardiomyocytes on an elastomeric body enclosing a microfabricated gold skeleton, we replicated fish morphology at Embedded Image scale and captured basic fin deflection patterns of batoid fish. Optogenetics allows for phototactic guidance, steering, and turning maneuvers. Optical stimulation induced sequential muscle activation via serpentine-patterned muscle circuits, leading to coordinated undulatory swimming. The speed and direction of the ray was controlled by modulating light frequency and by independently eliciting right and left fins, allowing the biohybrid machine to maneuver through an obstacle course.
Science fiction great Philip K. Dick pioneered the idea of things that were part inorganic device, and part living being in his 1955 story Service Call:
The directing neurological tissue that forms the basis of the swibble is alive, certainly, in the sense that it grows, thinks, feeds, excretes waste. Yes, it's definitely alive. But the swibble, as a functioning whole, is a manufactured item. The organic tissue is inserted in the master tank and then sealed.
(Read more about PKD's swibble)