Xenobots: World's first living robots created from frog stem cells

Scientists have created the world's first living robots by assembling stem cells from frog embryos.

It is named as "Xenobots" after the African clawed frog Xenopus laevis from which the stem cells were taken. The machines are less than a millimetre (0.04 inches) wide -- small enough to travel inside human bodies, reports CNN.

These new creatures were designed using a supercomputer and then built by biologists. They could now be used for a variety of different purposes, scientists behind the creation said.

Researchers have turned the cells into a machine that can be programmed to work as they wish, reports Independent.

Designing robots out of such living materials could lead to vast changes in the way that technology is used, the scientists suggest. Xenobots can regenerate and are entirely biodegradable when they die. They are able to repair themselves.

Unlike traditional materials, the robots can be sliced almost in half and will fix themselves back together again, scientists claimed.

It is the first time that humanity has been able to create "completely biological machines from the ground up", the team behind the discovery write in a new paper. It could allow them to dispatch the little "xenobots" to transport medicine around a patient's body or clean up pollution from the oceans, for instance. They can also heal themselves if they are damaged, scientists claimed.

"These are novel living machines," said Joshua Bongard, the University of Vermont expert who co-led the new research.

"They're neither a traditional robot nor a known species of animal. It's a new class of artefact: a living, programmable organism," he said.

"We can imagine many useful applications of these living robots that other machines can't do like searching out nasty compounds or radioactive contamination, gathering microplastic in the oceans, travelling in arteries to scrape out plaque," said co-leader Michael Levin who directs the Center for Regenerative and Developmental Biology at Tufts University, where the xenobots were actually created.

The team described the major breakthrough in a paper published in the Proceedings of the National Academy of Sciences.

The second part of the research saw a microsurgeon and other researchers turn those designs into real life. They took stem cells from the embryos of African frogs, incubated them, and then used incredibly tiny tools to cut them apart and assemble them into the design that the computer had created.

That meant that scientists had stuck real organic material together to create a life-form that had never been seen before in nature.

After that happened, the cells started to work together. Just as the computer had suggested, the robots were able to move on their own, eventually doing so in a coherent fashion and exploring their environment over a matter of weeks.

A xenobot with large hind limbs and smaller forelimbs, layered with red heart muscle.

They were able to work to push pellets around, organising themselves spontaneously and collectively, according to the researchers.

Researchers admit that there is the danger that such developments could be harnessed in ways that we don't even understand, leading to unintended consequences. If the systems become sufficiently complex, it might be impossible for humans to predict how they will start to behave.

"If humanity is going to survive into the future, we need to better understand how complex properties, somehow, emerge from simple rules," said Levin in a statement.

"This study is a direct contribution to getting a handle on what people are afraid of, which is unintended consequences," he said.

He said that the new study is an important step towards understanding such systems. By learning more about how living systems decide how they will behave, and whether and how that might be changed, we will be able to better understand their outcomes.

Scientists predicting that they will be able to create even more complex versions of the xenobots. Computer simulations suggest that it should be possible to design the xenobots with a pouch on their body that could be used to carry an object – delivering a drug by swimming through the body, for instance.