The study of the origins of the earliest life (abiogenesis) is an exciting and interesting field of research. However, the field is fraught with technical difficulties. After all, these scientists are trying to reproduce what happened billions of years ago. Yet, significant progress has been made beginning with the Miller-Urey experiments to today’s ongoing experiments.
Recently, Gerald Joyce and Tracey Lincoln‘s findings have added to the growing body of knowledge on abiogenesis. Their work is to further the model known as the RNA-world hypothesis. Briefly, this theory holds that the original heredity molecule when life was just beginning was actually RNA, a close relative of DNA. This theory is attractive because RNA can store genetic material and act as an enzyme itself. Joyce and Lincoln’s recent work showed that under lab conditions, that RNA alone was sufficient to reproduce in such a way that allowed for slight changes in sequence. Over the course of the experiment, these slight changes led to better and better reproducing RNAs or, in other words, they evolved.
Discovery Institute’s take
As I have said before, strict evolutionary theory does not include abiogenesis. That doesn’t stop the Discovery Institute’s Evolution News and Views blog from focusing on it. They aren’t going to let any experimental findings get in the way of their preconceived notions of the beginnings of life on earth. In this case, Casey Luskin wrote a post criticizing these findings.
Luskin’s criticism of the work largely focuses on how the experiments performed (original emphasis):
Origin of life researchers are excited about [the research] because they think it shows one possible step in their story about how life might have arisen via natural processes, without intelligent design (ID). One big problem with their story: under no uncertain terms did natural processes produce this molecule.
The point of the research was not to replay the origin of life from the beginning as Luskin is implying. The point was to take RNA molecules that can replicate and see if they can adapt to new conditions. Joyce and Lincoln’s work nicely shows that this is possible. Luskin completely misses the point here and is arguing with a strawman. Other researchers are trying to figure out what the earliest “biological” molecules looked like, but that is not the focus here.
Luskin goes on to produce a list of 5 complaints that came from an unnamed pro-ID chemist. Let;s take these criticisms one at a time:
1. The system is completely contrived consisting ONLY of catalysts and substrates. No competing materials or reactions were allowed. No natural analog is possible.
One of the strengths of modern scientific method is that the best experiments are tightly controlled. The reason for this is so that results are reproducible and are due to only the variables being studied. Adding “competing materials or reactions” introduces unnecessary variables. Luskin’s complaint goes against doing science the correct way.
2. There is a vast gulf between their reaction mixtures and anything that might possibly come from a Stanley Miller type electric discharge experiment. This requires explanation.
Again, the point here is study RNA molecules, not how the original organic molecules formed on earth. Besides, Stanley Miller’s experiments are not the only way to produce organic molecules.
3. The 5’-end of the oligonucleotides were primed for the condensation reaction by prior synthesis of the high energy triphosphate form. Simple phosphates fail to react or react at rates orders of magnitude slower. Clearly the reaction only does what the chemist intended.
The unnamed chemist seems to have a problem with presence of high energy triphosphates. We don’t know whether or not there were these phosphates present during abiogenesis. This argument from ignorance is just a diversion and was not the question the scientists were testing. However, an interesting proposal for these high energy phosphate production is that it came from meteor impacts.
4. Reactions were carried out at 42 deg C. –> fine-tuning –> fine-tuner!
This goes back to controlling variables. One temperature means one variable. Having the reactions occur at any random temperature would only complicate the issue. Besides, 42 deg C is a very common temperature that is used in labs.
5. Only one bond is formed by either of the paired enzymes. The rest of the molecule was pre-assembled by Joyce and his colleagues. What this experiment shows is that some clever chemists have spent ten years of their lives re-engineering a pair of RNA-zymes to catalyze ONE reaction. And without a constant supply of pre-fabricated component parts, nothing happens. Indeed, if anything, the road to self-assembly just got longer.
Unfortunately, I do not have access to the full article, so I cannot fully respond to this point. However, the two news releases that I have read seem to imply that the scientists did not preassemble anything but the starting RNA molecules. If anyone else has more information, I would love to know.
Luskin glosses over perhaps the most important finding of the research. The RNAzymes were able to adapt and by the end of the experiment could outcompete the RNA molecules at the beginning of the experiment. Luskin again shows us that he understands very little of modern science. It is a shame that anyone listens to this drivel as a source of news.
One final point. These experiments have to be done on human timescales. We can’t spent thousands or millions of years reproducing the early earth.
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