A group of researchers working for Google argues it now can simulate the rise of self-replicating life forms in a digital computer simulation, that is to say, an experiment somewhat parallel to the primordial crust of life on Earth. Results from the experiment, yet to be peer-reviewed, throw new light on some new theories about the origins of biological life.
“Managing to evolve self-replicating programs from random starting points is a great achievement,” said Susan Stepney of the University of York, UK, who wasn’t part of the research group. She said it represented an important step toward understanding possible routes for the emergence of life, despite being in a medium very far removed from the conventional biological setting.
It runs parallel to the “primordial soup” theory of life emerging from a mixture of water and organic compounds. Billions of years later, this was to turn into the first organisms from what was originally a chaotic blend. Co-author Ben Laurie, a software engineer at Google, explained that it was not magic, but physics, rather, if you wait this many years, then complex things will eventually happen.
Laurie and his colleagues did the same for the primordial soup, but on a computer, using a minimalistic programming language called Brainfuck. This language could have at most only two mathematical operations, adding one and minus one. To let the language become free, behaving exactly like those free molecules that would combine in whichever way they want, the team fine-tuned this language so that random data played the role of molecules interacting with each other in the complete absence of any imposed rules or impetus from the outside. Under these very rigidly constraining conditions, self-replicating programs nonetheless showed up.
The results suggest, according to Laurie, that there are underlying mechanisms ordained to make life appear. However, experts appreciate that self-replication is not tantamount to life. Richard Watson of the University of Southampton, UK put a comment saying that although complexity in the programs increased after the start of self-replication, really it didn’t “take off” in a way one expects compared with what would be considered exciting or lifelike.
Practical limitations perhaps played a part here. Laurie suggested that with more computing power they would have witnessed more complex programs evolve; he hinted that repeating the experiment with more powerful hardware could produce even closer approximations to lifelike forms.
It is now opening up new avenues for understanding the origins of life, by offering a digital lens through which one of the deepest questions in science can be explored.