Imagine thousands of tiny life-forms created by computers. Their behavior is programmed by artificial intelligence, but they are made from living cells. They are preloaded with their own food source and have no head, eyes, nor other sense organs. But they are very much alive. They can carry out a task and — get this — they can be cut in half, repair themselves, and then keep on going.
Sounds scary, right? It’s not the latest science fiction production. It is, in fact, reality. A team of scientists has created just this type of organism. It’s a living robot and, while just a fraction of a millimeter in width, it looks like an innocent piece of popped popcorn. And the practical implications could actually be pretty useful.
The scientists, from the University of Vermont and Tufts University, repurposed living skin and heart muscle cells, which they took from frog embryos, and assembled them using artificial intelligence into entirely new life-forms. They’re called xenobots, named for the African frog genus that donated the cells, and they can move toward a target, pick things up, and heal themselves. They can walk, swim, push or carry an object, and work together in groups. Then, after several days, they die like any other life-form and are as useless as dead skin cells.
“These are novel living machines,” says Joshua Bongard, a computer scientist and robotics expert at the University of Vermont, who co-led the new research. “They’re neither a traditional robot nor a known species of animal. It’s a new class of artifact: a living, programmable organism.”
The new creatures were designed on a supercomputer at UVM and then assembled and tested by biologists at Tufts University. The accomplishment marks the first known time that life has been created by computers, and these results were published on January 13 in the Proceedings of the National Academy of Sciences.
This research, for the first time ever, “designs completely biological machines from the ground up,” the team writes in their new study.
Their creation took months of processing time on supercomputers at UVM, known as the Deep Green supercomputer cluster at UVM’s Vermont Advanced Computing Core. The team, including Bongard and lead author and doctoral student Sam Kriegman, used complex equations, called algorithms, to create thousands of potential designs, ultimately keeping the successful ones and scrapping the ones that didn’t work. Then the team at Tufts transferred the best designs into life-forms by gathering stem cells from frog embryos and using tiny forceps and electrodes to cut and join the cells under a microscope, creating tiny life-forms to match the designs specified by UVM’s supercomputer.
Once they were assembled into body forms never before seen in nature, the cells began to work together. The skin cells formed a more passive architecture, while the once-random contractions of heart muscle cells were put to work creating ordered forward motion as guided by the computer’s design.
The xenobots also made spontaneous self-organizing movements, allowing the robots to move on their own. They demonstrated that they could move around in circles and push tiny pellets into a central location, working as group.
The implications of these findings include advancements in medicine and environmental remediation. For example, the xenobots could safely deliver drugs inside the human body. “It’s a step toward using computer-designed organisms for intelligent drug delivery,” says Bongard.
The xenobots could also put their group-work together to clean up the oceans, as Bongard explained during a recent interview with BBC World Service.
“At the moment, it is very difficult to locate and clean up microplastics in the ocean,” he explained. “But in the future, you could imagine a swarm of the biobots sprinkled on the surface of the ocean, and each of these biobots would be tasked with finding a small pellet of microplastic and then shepherding these micropellets into a massive ball of waste. Then, more traditional methods, like a boat, could come and take the waste away.”
This research also broadens our understanding of the diverse forms and functions life may adopt. What these researchers have been learning about how cells communicate and connect extends deep into both computational science and our understanding of life.
“The big question in biology is to understand the algorithms that determine form and function,” says Michael Levin, a co-leader of the study, who directs the Center for Regenerative and Developmental Biology at Tufts. He explains, while the genetic code of a life-form dictates how it is built, there is the possibility that these processes can be rebuilt. The scientists involved in this study see their recent work with the xenobots as one step in developing and applying new insights about the interplay between biology and computers.
Says Levin, “You look at the cells we’ve been building our xenobots with, and, genomically, they’re frogs. It’s 100% frog DNA, but these are not frogs. Then you ask, well, what else are these cells capable of building?”
The researchers have created a website to showcase their research. It includes more information, images, videos, press clips, and frequently asked questions. To learn more, visit https://cdorgs.github.io/.