A study published in the Proceedings of the National Academy of Sciences on Monday shows that researchers who developed the world's first living robot now report they can reproduce in an unprecedented way.
Last year, researchers at the University of Vermont and Tufts University described a new type of robot called the xenobots. The stem cell bundles of the African clawed frog are cultivated into the xenobots. The University of Vermont computer scientist and robotics expert, Joshua Bongard, referred to them in a press release last January as "novel living machines" that are a "new class of artifact: a living, programmed organisms."
The initial shapes of the xenobots are what determine their behavior. The researchers devised thousands of possible designs for their novel lifeform, with the capacity for unidirectional locomotion being a fundamental physical requirement. The cells were assembled to match the computer design. The xenobots can live for days to weeks in an aquatic environment using their cells. They biodegrade after their lifetimes are extended with a rich environment.
The definition of a robot was never easy, although older technologies made it seem like we knew what a good definition of a robot was. The technology makes it clear that there are some important knowledge gaps around the concepts of robot, machine, organism, program, etc.
Researchers from the two universities as well as Harvard University's Wyss Institute for Biologically inspired Engineering reported that the xenobots are autonomously making more of themselves using a method previously unknown to be used by any animal or plant species. The method, called kinematic replication, left him astounded.
The team observed the xenobots, which are made from around 3,000 stem cells each, moving around a petri dish to collect stray stem cells and form them into clumps. The clumps of stem cells became new xenoBots. Bongard told CNN that the team used the supercomputer to test billions of body shapes to determine the ideal form for the collection, and it ended up spitting out something that looked a lot like Pac-Man. The C-shaped xenobots were more effective at catching stem cells and forming new xenobots than the standard form.
Bongard told CNN that most people think of a robot as made of metals and ceramics, but what it does is what matters. We usually think about writing code when we think about the machines that the artificial intelligence programed. It created a shape of the game.
Bongard told CNN that the shape is the program and how the xenobots act to amplify the process.
Bongard told Gizmodo that frog cells were used because they are one of the most common organisms used in biological studies. Douglas Blackiston has experience working with frog tissue. Bongard explained that the team's previous research into inducing the xenobots into specific behavior led to the discovery they could replicate themselves.
Bongard told Gizmodo that the frog heart muscle tissue was included in the first experiment in January 2020. In a second paper from March 2021, we showed that there are small hairs on the outer surface of a robot. They beat the cilia to swim, which results in quicker movement. We showed that we could get the bots to say things like'see','remember', and 'come back'.
They would switch to glowing red when they came into contact with blue light. We could tell how many bots had seen the blue light by counting the red bots at the end of the experience. We showed that a randomly- moving xenobot swarm would cause pellets in their environment to be pushed into piles. This was part of the inspiration for the current work. This led to the idea of replacing the pellets with individual cells to see what would happen.
Bongard told Gizmodo that it was never observed or believed to occur in organisms. The study states that the stem cells weren't spontaneously combining in the absence of the xenobots.
The authors of the study said that the origin of life on Earth could be explained by the swerving of the xenobots. The amyloid world hypothesis states that self-assembling peptides were the first molecule capable of self-replication and would thus represent the earliest stage in the evolution of life. They said the study could contribute to the understanding of how self-amplifying processes can emerge spontaneously, in new ways and in new forms. On their website, the team speculates that understanding of cell biology could be improved by the use of xenoBots.
Bongard said there was no telling what future xenobots would be used for. Bongard wrote that it was impossible to know what applications a very early-stage technology like xenobots would have. The advantages of this technology are that they are small and happy in water, and that they are not harmful to the environment.
Bongard said that with the right regulation in place, they may be able to inspect plant roots in vertical farms, facilitate cultured meat production, or lower the cost of producing fresh water in desalination facilities.
According to Levin, there may be applications for xenobots in several areas. He wrote that one of the synthetic living machines is useful for sculpting tissues for transplants, in the body in in-vitro for sculpting of tissues for transplants, in production facilities/plants, in the environment, in exploration, etc.
The lessons of the xenobots will help scientists better understand and control the goals and behavior of swarms of active agents, which will help us make sure that the Internet of Things, swarm robotics, and many other technologies actually have beneficial outcomes.
