Metrolab Blog

Meet Xenobot, an Eerie New Kind of Programmable Organism

Researchers hope the living robots, made up of masses of cells working in coordination, can help unlock the mysteries of cellular communication.

image of the organism's group behavior
Xenobots carve traces through a field of particulate matter. These simple robots made of cells exhibit remarkably complex behavior.COURTESY OF DOUGLAS BLACKISTON

UNDER THE WATCHFUL eye of a microscope, busy little blobs scoot around in a field of liquid—moving forward, turning around, sometimes spinning in circles. Drop cellular debris onto the plain and the blobs will herd them into piles. Flick any blob onto its back and it’ll lie there like a flipped-over turtle.

Their behavior is reminiscent of a microscopic flatworm in pursuit of its prey, or even a tiny animal called a water bear—a creature complex enough in its bodily makeup to manage sophisticated behaviors. The resemblance is an illusion: These blobs consist of only two things, skin cells and heart cells from frogs.

Writing today in the Proceedings of the National Academy of Sciences, researchers describe how they’ve engineered so-called xenobots (from the species of frog, Xenopus laevis, whence their cells came) with the help of evolutionary algorithms. They hope that this new kind of organism—contracting cells and passive cells stuck together—and its eerily advanced behavior can help scientists unlock the mysteries of cellular communication.

How cells work together to form intricate anatomies “is a major puzzle,” says Tufts University developmental biophysicist Michael Levin, coauthor on the new paper. “What we’re very much interested in is this question of how cells work together to make specific functional structures.” Once they start probing that unknown, they might even make headway on the more mysterious question of what else a cell might be willing to make.