I feel responsible for this thread going on for nearly 400 posts, almost none of them dealing directly with the article I referenced (fee access to which has expired by now). I fear the fault lies in my careless wording and over simplifications in the OP.
Here is what I wrote:
An interesting article in the Washington Post adds momentum to the RNA world theory. Self-replicating RNA has been created in a lab. The copies made are quite similar to the original, which has apparently been a stumbling block to earlier efforts. We are inching forward to the creation of life in a test tube.
Let me rephrase and expand on that with a number of quotes from the article. (I have re-shared the article so it will be accessible again hopefully).
An
interesting article in the Washington Post adds momentum to the RNA world theory. Self-replicating RNA has been created observed in a lab copying other types of RNA molecule.
The copies made are quite similar to the original, but not absolutely identical.
An RNA molecule must make copies very close to the original to achieve the same delicate balance that governs Darwinian evolution in nature. If the copies change too much, the RNA’s abilities degenerate, and things go downhill quickly. Imagine a malfunctioning photocopier that makes a fuzzy or faded copy of an image. When placed in the machine, the fuzzy copy produces a new one that is even worse.
“If the error rate is too high, you can’t maintain the [genetic] information,” Joyce said. “It just blows up.” The errors happen too quickly to allow Darwinian selection to pick the winners, those best equipped to survive, and “round by round of evolution you just see the population dissipate into no man’s land.”
In the new work, the Salk scientists created an RNA that makes copies of something called a hammerhead RNA. Instead of copying other RNA molecules, the hammerhead chops them. When the RNA made copies of the hammerhead, each new generation could still chop; each also grew easier to copy.
To show that their RNA was getting better at copying, the Salk team tested a 71st-generation version against one of its distant ancestors. The newer generation outperformed its ancestor when it came to making accurate copies.
In other words, scientists created the initial conditions, and then observed over a number of months while a sort of proto-Darwinian evolution took place (my words).
The central point, Joyce said, is that “eventually Darwinian evolution began to operate,” and at some point early in the history of life, RNA fulfilled the crucial roles of holding genetic information and accelerating the chemical reactions needed to make copies of that information.
Should the scientists succeed in generating an RNA that can copy itself, evolution could then proceed largely on its own.
Note the use of “generate.” There’s a subtle difference from the word “create.” There was some initial creation of an environment, but then the scientists let nature take over.
We are inching forward to the creation of life in a test tube.