American scientists have created the world’s first living robot, known as the xenobot. They can replicate themselves in a way that is entirely different from natural animals and plants.
Made from stem cells of the African clawed frog, xenobots measure less than 1 millimeter in diameter. These tiny, blob-like creatures were introduced in 2020, after numerous experiments demonstrated that they could move, group together, and heal themselves.
Now, the scientists who created them at the University of Vermont, Tufts University, and the Wyss Institute for Biologically Inspired Engineering at Harvard University report that they have discovered a completely new form of reproduction unlike any known in the animal or plant kingdom.
Image of self-replicating xenobots.
“I am absolutely amazed by this,” said Michael Levin, a biology professor and director of the Allen Discovery Center at Tufts University, who is one of the researchers involved.
Stem cells are unspecialized cells capable of developing into various types of cells. To create xenobots, researchers used living stem cells from frog embryos and allowed them to grow. There was no genetic manipulation involved. “Most people think of robots as being made of metal and ceramics, but these are made from biological material, allowing them to act on their own behalf,” explained Josh Bongard, a professor of computer science and robotics at the University of Vermont.
“In that sense, it is a robot, but also a living organism made from unmodified frog cells,” he added.
Bongard stated that the research team discovered that xenobots can replicate themselves. These xenobots initially take on a spherical shape, composed of about 3,000 cells. However, replication occurs infrequently and only under specific conditions. They utilize “kinetic replication,” a mechanism that occurs at the molecular level but has never been observed at the cellular or organism level before.
Xenobots still represent early-stage technology, much like computers in the 1940s, when many practical applications had yet to be discovered. Researchers say that the combination of molecular biology and artificial intelligence could lead to various applications such as cleaning up plastic waste in oceans or advancements in regenerative medicine.
While the potential applications of self-replicating technology may raise concerns, researchers emphasize that these living machines are fully controlled in the laboratory and can be easily disposed of.
This research is funded by the Defense Advanced Research Projects Agency (DARPA), a U.S. federal agency that supports and oversees the development of technologies for military purposes.
