The Tiny Living Robots That Can Reproduce: Welcome to the World of Xenobots

May 3

If you thought today would be a normal day where you read about normal things happening in the world, think again. I’m here to rock your world and maybe horrify you a little bit. You’re welcome.

Okay, so imagine a couple of tiny, blob-like creatures swimming under a microscope…not quite alive in the traditional sense, but not really mechanical either.
They’re made of living cells, but they’re engineered. And here’s the kicker that might keep you up at night: they can replicate themselves.

Dum-dum-dum-dum.

Meet the xenobots, tiny programmable living robots made from frog cells that just might be giving us a peek at the future of biotechnology.

Welcome to the strange world of self sustainable robots.

What Exactly Are Xenobots?

Okay, so apparently back in 2020, a team of researchers from the University of Vermont and Tufts University announced they had created the first-ever xenobots. The project was led by Dr. Josh Bongard (UVM computer scientist) and Dr. Michael Levin (Tufts developmental biologist). Named after the African clawed frog (Xenopus laevis) whose cells they’re made from, these little bots are a strange mashup hybrid of biology and robotics.

But they’re not made from wires and circuits. Oh no, instead, scientists took living skin cells and heart cells from frog embryos and shaped them into tiny blobs that could move around on their own. Some were designed to push microscopic particles, while others could walk.

In other words, they’re like tiny, programmable living machines.

Pretty wild, no? But here’s where it gets even crazier.

The Breakthrough

At first, xenobots could do simple things: move in a petri dish, transport tiny payloads, maybe even heal themselves if they got hurt.

But in late 2021, researchers noticed something unexpected. Some xenobots weren’t just moving around, they were gathering loose cells and assembling them into new xenobots.

Yeah, you read that correctly. They were literally creating more of themselves!!

This is called kinematic self-replication, and it had never been seen in multicellular organisms before this point. Normally, living things reproduce using growth or division. Xenobots? They scoop up loose cells and “build” themselves some little babies.

And yes, it sounds eerily close to the kind of replication we associate with robots in movies. But these aren’t metal machines, they’re made of 100% biological material.

If this didn’t blow your mind enough, in 2021, researchers gave xenobots a primitive kind of memory.

So they can’t think about the time they got in trouble in the forth grade when they copied off Jessica sitting next to them, or the time they walked into some broken glass with their bare feet when they were 12, but they can store simple information about what they’ve experienced, which, for a cluster of frog cells with no brain or nervous system, might be more impressive than my own 2am stream of life regrets that plays in my mind.

The same team, led again by Dr. Michael Levin at Tufts University and Dr. Josh Bongard at the University of Vermont, achieved this by embedding a molecular switch inside the cells. They used a protein known as EosFP (yeah, I had no idea what that is either and had to look it up) a special fluorescent molecule that changes color when specific wavelengths of light hit it.

So normally, EosFP glows green, but when scientists shine a certain light (around 390 nanometers), it permanently turns red. By shining this light on a xenobot, researchers could mark that it had been “exposed” to something, essentially flipping a biological bit from 0 to 1.

Later, when the xenobot was examined under a microscope, scientists could “read” its state by the color, whereas green meant no exposure, red meant yes, I was here, I did this.

That’s biological memory, written directly into living tissue.

It may sound a little less dramatic than you were hoping for, but it’s actually groundbreaking. It proves that programmable living systems can not only move and act but also record what happens to them in some way.

What can we use them for?

If your brain just went straight to “so, like… are they gonna take over?”, don’t worry. We’re not talking about rogue replicating robots like in iRobot or anything like that. Xenobots are tiny (less than a millimeter), they die after about a week (sad), and they need very specific lab conditions to survive.

Scientists think xenobots could someday be used for cleaning up microplastics in oceans (imagine sending little biological bots to collect plastic particles), targeted drug delivery inside the human body, regenerative medicine (think tiny helpers building tissue), and basically studying cellular behaviors in ways we couldn’t before now.

I can’t help but wonder are xenobots alive? Are they robots? Should there be rules about creating self-replicating systems, even if they’re microscopic?

For now, xenobots can’t survive outside lab dishes. They don’t eat, grow, or mutate on their own yet it seems like, but I still wonder if they have any consciousness at all.

How Xenobots Compare to Other Biotech

If you’ve read my piece on artificial photosynthesis, you know I’m fascinated by the blending of natural processes with engineered solutions. Xenobots feel like they’re in the same family, but maybe more like a crazy cousin three times removed, using biology’s own toolkit, but steering it toward something new.

It’s not about building cyborgs or androids, it’s more about leveraging living systems as programmable tools, a completely different paradigm from traditional robotics or pharmaceuticals.

Could I get my own Xenobot?

Eh, no, I don’t think so. Don’t expect to pick up a xenobot cleaning kit at Target anytime soon, this tech is still deep in the research phase.

I suppose that similar fields (like synthetic biology and biocomputing) are advancing quickly and realistically Xenobots might be a glimpse into how we’ll one day design biological machines to work alongside us.

And just imagine: instead of using plastic or metal, future tech could be grown from living cells, designed to break down naturally or even heal itself.

It’s like nature and technology aren’t competing anymore, they’re merging. I can’t tell you how much I love that idea.

Want to Explore Biotech Yourself?

If reading about xenobots makes you want to geek out in your own kitchen (without needing a lab), check out this home DNA extraction kit I found. It’s an affordable way to experiment with genetics in a hands-on, safe way. Definitely a fun weekend project if you’re curious about biology!

Reads You Might Enjoy:

Michele Gargiulo http://michelegargiulo.com