Xenobots: scientists create self-replicating robots

American scientists who created the first living robots say life forms known as xenobots can now reproduce in ways that are not seen in plants and animals. Formed from the stem cells of the African clawed frog (Xenopus laevis), from which it gets its name, xenobots are less than a millimeter (0.04 inches) wide. The tiny blisters were first discovered in 2020 after experiments showed they could move, work together in groups, and heal themselves.

Now the scientists who developed them at the University of Vermont, Tufts University and the Wyss Institute of Biological Engineering at Harvard University say they have discovered an entirely new form of biological reproduction, unlike any animal or plant known to science.

“I was surprised by this,” said Michael Levin, professor of biology and director of the Allen Discovery Center at Tufts University, who is co-author of the new study. “Toads have a way of reproduction that they usually use, but when you release (cells) from the rest of the embryo and give them a chance to figure out how to be in a new environment, they don’t just discover that they are.” We found a new way of locomotion, but also, apparently, discovered a new way of reproduction. “

This new form of reproduction forces xenobots to efficiently harvest free stem cells, collecting them in piles, which can then grow into xenobots.

Realizing that the shape of the xenobots was holding them back, the researchers used AI to test many new body shapes to maximize the stem cell harvesting process. The AI ​​has evolved into a C-shape reminiscent of the game’s iconic Pac-Man character.

“AI did not program these machines in the way we usually think of writing code. He shaped, sculpted and designed the Pac-Man shape, ”said study lead author Josh Bongard, professor of computer science and robotics expert at the University of Vermont. “Form is essentially a program. Form affects the behavior of xenobots to enhance this incredibly amazing process. “

Although the idea of ​​self-replicating machines is reminiscent of names like The Terminator. about the future and other similar films, the researchers are confident that these robots are contained in the laboratory, are biodegradable and easily die out. But the discovery of self-replicating robots opens up a whole new world of possibilities. A little more useful than humanoid robots proposed by Elon Musk…

“Much is possible if we take advantage of this plasticity and the ability of cells to solve problems,” Bongard said. The study was originally published in Scientific journal PNAS revised in pairs 20 November 2021