A team of scientists at Tufts University in the US have created xenobots, tiny robots made from frog skin and heart cells that can walk, work together and heal themselves.
Algorithms define the configurations of frog cells, which are then constructed by humans to create a living robot that the scientists have called a xenobot, after the Xenopus laevis species of frog they are made from.
Xenobots are made from heart and skin cells harvested from frogs
These aquatic organisms live for up to seven days, and the team hopes that in future they can be used to deliver drugs into people's bloodstreams, clean up microplastics from the ocean, or manage radioactive waste spills.
A number of variations of the 0.7 millimetre-long robots are designed using a computer algorithm. "Computers model the dynamics of the biological building blocks (skin and heart muscle) and use them like LEGO bricks to build different organism anatomies," said the team of scientists.
"An evolutionary algorithm starts with a population of randomly-assembled designs, then iteratively deletes the worst ones and replaces them by randomly-mutated copies of the better ones," they added.
"It is the survival of the fittest, inside the computer."
The computer produces a design, left, which is used to create the living robot on the right
The team included Douglas Blackiston, a research scientist and microsurgeon, Sam Kriegman, a PhD student and artificial intelligence expert, Tufts Universi...