'This is profound': Scientists create self-replicating robots from frog cells
TORONTO -- Scientists in the United States have created robots that can spontaneously self-replicate in what they’re calling a “profound” discovery.
The study, published on Monday in Proceedings of the National Academy of Science, found that these computer-designed and hand-assembled organisms called “xenobots” can reproduce in a method not seen in plants and animals.
"People have thought for quite a long time that we've worked out all the ways that life can reproduce or replicate, but this is something that's never been observed before," Douglas Blackiston, co-author and a senior scientist at Tufts University and Harvard University, said in a news release.
The xenobots were first developed and reported in 2020. They are made from about 3,000 embryonic skin cells of an African clawed frog.
The researchers discovered that these xenobots -- when designed properly -- can swim around while collecting hundreds of single cells to assemble smaller versions of themselves in their mouths. These smaller xenobots can grow to be full-size within a few days.
This method of reproduction is known as kinematic replication and is common in molecules, but has never been seen in cells or organisms.
"This is profound," Michael Levin, a co-leader of the study and a professor of biology and director of the Allen Discovery Center at Tufts University. "These cells have the genome of a frog, but, freed from becoming tadpoles, they use their collective intelligence, a plasticity, to do something astounding."
To discover the xenobots’ reproduction capabilities, the researchers used a supercomputer at the University of Vermont to simulate billions of body shapes to determine what would be ideal for kinematic replication.
Months later, the computer returned a xenobot in a shape that resembled a Pac-Man figure, with a large mouth that can be used to build other xenobots.
“It looks very simple, but it's not something a human engineer would come up with,” said Sam Kriegman, the lead author of the study and a post-doctoral researcher at Tufts University and Harvard University.
For those concerned about the idea of self-replicating biotechnology, the researchers stress federal, state and institutional ethics experts also approved the study. It is also contained in a lab and can be extinguished easily.
“What presents risk is the next pandemic, accelerating ecosystem damage from pollution, (and) intensifying threats from climate change," said Joshua Bongard, a computer scientist and robotics expert at the University of Vermont.
"This is an ideal system in which to study self-replicating systems. We have a moral imperative to understand the conditions under which we can control it, direct it, douse it, exaggerate it."
The researchers also note that this technology has a host of potential benefits for humans, including regenerative medicine, cleaning ocean pollution and vaccine research.