The tiny hybrids are “entirely new life-forms” known as xenobots – named after the African frog used in the research – and are able to move about.
It is hoped the millimetre-wide bots could one day be used to swim around human bodies to specific areas requiring medicine, or to gather microplastic in the oceans.
“We here present a method that designs completely biological machines from the ground up,” the team from the University of Vermont writes in Proceedings of the National Academy of Sciences.
Unlike the metal robots we have become accustomed to, biological tissues present the potential advantage of being able to heal too, though it remains very much in the early stages.
“These are novel living machines,” said Joshua Bongard, a computer scientist and robotics expert at the university, who co-led the breakthrough.
“They’re neither a traditional robot nor a known species of animal. It’s a new class of artifact: a living, programmable organism.”
An algorithm running on a supercomputer created thousands of candidate designs for the new creature, before being assembled and tested by biologists at Tufts University.
“You look at the cells we’ve been building our xenobots with, and, genomically, they’re frogs,” said co-leader Michael Levin, from Tufts University.
“It’s 100% frog DNA – but these are not frogs.
“Then you ask, well, what else are these cells capable of building?
“As we’ve shown, these frog cells can be coaxed to make interesting living forms that are completely different from what their default anatomy would be.”