The living robot! Part-frog, part-machine

Xenobot: They can walk, swim, survive for weeks without food, and work together in groups.

Is it dangerous to create living robots? Using the cells of a frog and artificial intelligence, scientists have designed an entirely new life form small enough to travel inside a human body.

Imagine Lego bricks that are made out of living cells. You could put them together, however you wanted, and make them carry out whatever task you desired.

That is pretty much what scientists in the USA have just achieved.

Researchers from UVM and Tufts University worked together to prototype a whole new species, the xenobot.

First, the scientists decide on the simple action they want their biological robot to do. This could be reaching a destination, moving a smaller object, or grouping together.

The researchers then use a computer to figure out the perfect arrangement of cells to fulfil that particular function. An algorithm will run through hundreds and thousands of possible shapes.

Once they have the ideal design, the scientists use tiny forceps to piece together dozens of cells taken from a frog. They build the creature as best they can in a petri dish.

Some of the cells, grown like those from a frog’s heart, then contract allowing the new creature to move through liquid.

One day, researchers hope that similar creations will be able to carry out medical tasks such as delivering drugs to infected cells or targeting viruses. We could program miniature doctors that could propel themselves around our veins.

The xenobots are given enough food in their cells to survive for a week before they degrade naturally. This means they could carry out tasks inside a human body without causing any damage or leaving any waste.

The scientists have also made discoveries that they did not expect. When you cut a xenobot in half, it grows back together again.

It is very difficult to say with any certainty whether the xenobots are alive or if they are machines. They are built entirely from organic matter, not from wires and steel. But they cannot eat, grow or reproduce.

The shape they take and the functions they carry out are determined with the help of a machine, but they are still limited by the boundaries of biology.

Nonetheless, our culture is filled with warnings about “playing God”. Just think of Mary Shelley’s Frankenstein. Should we really be creating living robots?


Why not? A xenobot is fundamentally no stranger than a mule or a genetically modified crop. Existing parts of nature are simply being recombined. We are not creating anything radically new. If it can help us make breakthroughs in healthcare, then we should not hold back just because it ‘feels’ wrong. Novelty is always frightening. But it is also something to marvel at and enjoy.

Then again, many say, by using computers to design new life forms, we might accidentally create something unstoppable. A disaster situation is always unlikely but unless we put limits on what scientists can do, the worst is always possible. Life has a tendency to do whatever it can to survive. And while today we want to use xenobots to fight diseases, tomorrow they could be turned into weapons or worse.

You Decide

  1. Do you think it is wrong for scientists to build new life forms? Do you think it is the same thing as playing God?
  2. How would you feel if some of your own cells were used as the building blocks of a biological robot? Would you feel upset?


  1. In teams, design the shape and function of your own xenobot on a piece of paper. Then, as a class, vote on which group designed the best (you can’t vote for your own!).
  2. In groups of three or four, imagine that you are part of a team of scientists deciding what limits to place on the creation of artificial life. Make a list of five or six rules. What would you ban future scientists from building?

Some People Say...

“The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.”

Isaac Asimov (1920-1992), US writer and biochemistry professor

What do you think?

Q & A

What do we know?
The xenobots are named after Xenopus laevis, which is the scientific name for the African clawed frog. Each xenobot is about a millimetre wide. In 2012, scientists used rat cells to create jellyfish. In the past, genetic engineering has also enabled scientists to create fluorescent mice.
What do we not know?
If future biological robots could organically evolve and reproduce. We do not know if there is any way to stop some people from creating biological robots that seek to do harm instead of good. We also do not know if the xenobots count as animals and, if so, whether they should be protected by animal rights.

Word Watch

Original or test version of something.
Set of commands, like a recipe, used to programme machines.
Like tweezers with curved ends.
Petri dish
Circular case used to conduct cellular experiments and grow cell cultures.
Waste away.
Novel about a scientist who builds a monster out of different human body parts.
A cross between a horse and a donkey.

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