I was on call with my niece when she seemed distracted by something: a little capsule of an automatic vacuum cleaner had emerged from under her bed. She said, “I wish the vacuum would have babies so they could clean my Lego house!” Amusing as the thought was, it reminded me of an article I read about some living robots that had reproduced. Xenobots – the living proof of robots designed from animal cells. It is a wild concept that emerged as a reality late last year. How do these ‘living robots’ work? Are the ‘offspring’ linked to their parents? Are they a new species altogether? While these are questions that might be too much to discuss with a five-year old, they certainly are questions worth finding answers to.
Before understanding Xenobots, a brief background into robots and artificial intelligence is necessary. Unlike the unrealistic standards set by pop culture, robots are machines that can perform a set of physical actions and can make their own decisions. From something as complicated as a humanoid robot, like Honda’s Asimo, to something as simple as a Roomba, are all robots. Artificial Intelligence (AI) in its simplest terms is a computer algorithm that can learn a set of tasks or actions from a rudimentary set of input information.
Often, programming is viewed as something that employs multiple computer screens and coding languages. However, the most basic type is the kind that comes from scheduling one or more sets of actions. Things as simple as ensuring a light turns on when you flick a switch count as programming. So, when researchers from University of Vermont, Tufts University, and the Wyss Institute for Biologically Inspired Engineering at Harvard University, in early 2020 decided to predict what alien life could be like, they noticed they could recreate the solutions from the AI by using living cells from frog embryos as building blocks. The frog used, Xenopus laevis, inspired the name ‘Xenobot’.
Using the embryo skin cells for structure and heart cells for piston-like movement, they put together a block of living cells in a certain arrangement suggested by the AI using an evolutionary algorithm, which could allow the robots block to move around independently. These are Xenobots in their primary stage. Later, their shapes were modified to allow moving in circles in stage two.
Up until stage two, biologists sat, with a microscope, manually putting together these embryonic cells to produce each individual Xenobot. To save time and effort, they decided to experiment with how these robots could self-replicate. This would be possible via kinematic self-replication, which is a process by which synthetic multicellular assemblies (like Xenobots) may reproduce by moving and compressing dispersed cells in their surroundings into functioning self-copies. This has never been seen before in any creature, and occurs spontaneously within days rather than over millennia. For this process to happen, the Xenobots had to be shaped like Pac-Man, and much like Pac-Man, they would swim around collecting the cells together in clumps that fused to form identical Xenobots with identical behaviours, within days.
Xenobots are a fairly new invention and the scope of their use is unimaginable. As Joshua Bongard (computer scientist, robotics expert, and the co-leader of the project) rightly said in a podcast that no one had predicted how the development of the first computer would allow us to access social media from our phones today. Similarly, no one can predict the range of applications that Xenobots can be put to. So far, the team expects the primary areas of application to include decomposing microplastics from water bodies, and someday use a person’s own cells to create such medical robots to help remove brain tumour or clean up artery plaque, which the human body will not reject.
Xenobots, while promising, pose ethical concerns. As of now, Bongard states that Xenobots should not be considered as a new species altogether, and are certainly not something to be afraid of. Science fiction has led us to expect the worst of machines and human inventions. Xenobots have evolved after about 90% of designs by the AI were rejected, and their self-replication abilities only last up to five generations before dying out completely. If made from human tissues, these robots could raise more serious ethical questions which would require setting firm guidelines before further development.
Ultimately, Xenobots have opened up an avenue that no one knew of and it will produce more astonishing results in the near future. It is only a matter of time before more research flows in and sheds light onto the prospects of living robots. Until then one must keep asking questions, even if they involve cleaning Lego-houses.