New living robots made from frog cells can reproduce

By Tom Campbell via SWNS

Scientists have created living robots made from frog cells that can reproduce and could be the answer to everything from clearing rivers of microplastics to curing cancer.

The 'Xenobots' can assemble babies by swimming around and collecting hundreds of single cells in their Pac-Man-shaped mouths, according to a new study.

The newborn frog-bots can then repeat the process to build copies, which look and move just like themselves.

They could be deployed to remove pollution from rivers and oceans, while also helping find a cure for cancer.

Co-lead author Professor Joshua Bongard at the University of Vermont said: "We've discovered that there is this previously unknown space within organisms or living systems, and it's a vast space.

“How do we then go about exploring that space?

"We found Xenobots that walk. We found Xenobots that swim.

"And now, in this study, we've found Xenobots that kinematically replicate.

"What else is out there?”

The researchers scrapped living cells from frog embryos and assembled them into millimeter-wide robots using computer models.

Normally these cells would have developed into the frog's skin, but in this new context, they behaved differently, the researchers found.

Co-author Professor Michael Levin at Tufts University said: "These cells have the genome of a frog, but, freed from becoming tadpoles, they use their collective intelligence, a plasticity, to do something astounding."

The cells collaborated to perform basic tasks, like moving towards a target and healing themselves after being cut.

Now, the researchers have found these computer-designed organisms have gone one step further and have the ability to reproduce.

Professor Levin said: "We have the full, unaltered frog genome, but it gave no hint that these cells can work together on this new task of gathering and then compressing separated cells into working self-copies."

This new method of reproduction, known as kinematic replication, has never been observed in whole cells or organisms before.

Lead author Dr. Sam Kriegman at the University of Vermont said: “These are frog cells replicating in a way that is very different from how frogs do it.

"No animal or plant known to science replicates in this way."

If left to their own devices, the robots were able to replicate themselves, but they would then die out.

To overcome this, the researchers tested billions of body shapes using an artificial intelligence program, including triangles, squares, pyramids and starfish.

Dr. Kriegman said: "We asked the supercomputer at UVM to figure out how to adjust the shape of the initial parents, and the AI came up with some strange designs after months of chugging away, including one that resembled Pac-Man.

"It looks very simple, but it’s not something a human engineer would come up with.

"Why one tiny mouth? Why not five?

"We sent the results to Doug and he built these Pac-Man-shaped parent Xenobots.

"Then those parents built children, who built grandchildren, who built great-grandchildren, who built great-great-grandchildren.”

While some people may find the findings "exhilarating," others may react with "concern or even terror," the researchers say.

But their goal is a deeper understanding of replication and the tiny robots can be terminated in the blink of an eye.

Professor Bongard said: "The world and technologies are rapidly changing, and it's important for society as a whole that we study and understand how this works.

"These millimeter-sized living machines, entirely contained in a laboratory, easily extinguished, and vetted by federal, state and institutional ethics experts, are not what keep me awake at night."

The robots' AI could help solve some of the biggest environmental and health challenges the world is facing today, from regenerative medicines to clearing rivers of microplastics.

Professor Bongard said: "If we knew how to tell collections of cells to do what we want them to do, ultimately, that's regenerative medicine—that's the solution to traumatic injury, birth defects, cancer, and aging.

"All of these different problems are here because we don't know how to predict and control what groups of cells are going to build.

"Xenobots are a new platform for teaching us.”

He added: "We aim to accelerate how quickly people can go from identifying a problem to generating solutions, like deploying living machines to pull microplastics out of waterways or build new medicines."

The findings were published in the Proceedings of the National Academy of Sciences.