“A book is made of wood. But it is not a tree. The dead cells have been repurposed to serve another need.”
That’s quite the way to begin a press release.
The University of Vermont recently shared details on what their scientists have been up to lately. That is, using a supercomputer AI to construct robots made of living cells. The usual.
The bots, which measure up to a single millimeter in length, were created by “repurposing” the living cells of an African clawed frog, or Xenopus laevis. That’s where they get their not-at-all ominous moniker, Xenobots.
Research co-lead Joshua Bongard describes the xenobots as “neither a traditional robot nor a known species of animal.” They are, instead, “a new class of artifact: a living, programmable organism.” As such, they’ve been deemed the world’s first living robots.
As living organisms, they also benefit from certain factors that traditional robots might miss. Namely, they can heal themselves. The scientists practiced this by slicing the bots down the middle and watching them heal in response.
However, that bonus also comes with the major downside most living things face: They only live for about seven days before dying, expiring like Blade Runner‘s bioengineered replicants (though I doubt these bots will notice).
UVM researchers worked in conjunction with biologists at Tufts University to bring their xenobots to life. Together, they used an artificial intelligence algorithm run by UVM’s Deep Green supercomputer cluster to experiment with “thousands of candidate designs.”
“Attempting to achieve a task assigned by the scientists—like locomotion in one direction—the computer would, over and over, reassemble a few hundred simulated cells into myriad forms and body shapes. As the programs ran—driven by basic rules about the biophysics of what single frog skin and cardiac cells can do—the more successful simulated organisms were kept and refined, while failed designs were tossed out.”
After determining the best designs, Tufts University biologists took over, gathering stem cells from African clawed frog embryos and using them to assemble the xenobots based on those designs.
In the above image provided by UVM, you can see how the computer designed the xenobots. The green areas indicate frog skin cells, while the red areas are the heart muscle cells, which drive the bots’ forward motion. Left is the “anatomical blueprint” of the xenobot, while to the right is the resulting living organism.
Lead author Sam Kriegman shared a view of the final result on Twitter:
I'm thrilled to finally tell the world about computer-designed organisms aka "xenobots" aka "living robots" aka "reconfigurable organisms"…https://t.co/FQ5v23nKxY
You've heard of sim2real — this is sim2life. pic.twitter.com/w3dUB0nj5r
— Sam Kriegman (@Kriegmerica) January 13, 2020
As for what these xenobots may be used for, the possibilities range from cleaning up pollution to being sent inside the human body to scrape out plaque within arteries. According to Bongard, their development is also “a step toward using computer-designed organisms for intelligent drug delivery.”
However, even UVM delves into the more complicated questions regarding meddling with life itself to create new lifeforms. To that, Tufts team lead Michael Levin believes this might actually be a necessary step. “This study,” he says, “is a direct contribution to getting a handle on what people are afraid of, which is unintended consequences.”
The full paper, titled “A scalable pipeline for designing reconfigurable organisms,” can be found here.