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“Solution” to an Origin of Life Puzzle Highlights the Need for Careful Planning by an Intelligent Investigator

Casey Luskin

Stromatolites2.jpg

Last week they found the oldest human ancestor (a tiny scrap of a jaw) and now, as ENV earlier noted, they’ve solved a major puzzle in the origin of life. Science reports that “Researchers may have solved origin-of-life conundrum,” claiming that a new paper in Nature Chemistry may show that many building blocks of life could have been created through organic chemistry on the early Earth.

The Science report starts with what I’ve called in the past a “retroactive confession of ignorance.” What’s that? It is an admission that scientists didn’t know something — but suspiciously, these kinds of admissions come only after evolutionists think they have solved some problem. Not only do these make you wonder what unsolved evolutionary problems they’re refusing to admit right now, but the risk is that their “solution” itself won’t stand up to scrutiny. That would leave the confession twisting awkwardly in the wind. Here’s the confession from Science:

The origin of life on Earth is a set of paradoxes. In order for life to have gotten started, there must have been a genetic molecule — something like DNA or RNA — capable of passing along blueprints for making proteins, the workhorse molecules of life. But modern cells can’t copy DNA and RNA without the help of proteins themselves. To make matters more vexing, none of these molecules can do their jobs without fatty lipids, which provide the membranes that cells need to hold their contents inside. And in yet another chicken-and-egg complication, protein-based enzymes (encoded by genetic molecules) are needed to synthesize lipids.

But then immediately thereafter we read this: “Now, researchers say they may have solved these paradoxes.” Here’s what happened: In 2009, Cambridge University chemist John Sutherland and his team published a paper in Nature that claimed to have discovered a pathway to form two nucleotides used in RNA. We responded to this paper here and here.Their pathway, however, required acetylene and formaldehyde, which are not thought to have been present in any appreciable amounts on the early Earth. As the current Science news article explains: “Critics, though, pointed out that acetylene and formaldehyde are still somewhat complex molecules themselves. That begged the question of where they came from.”

Sutherland’s team got to work and tried to get around that problem, and according to Science, their new study indicates:

that it created nucleic acid precursors starting with just hydrogen cyanide (HCN), hydrogen sulfide (H2S), and ultraviolet (UV) light. What is more, Sutherland says, the conditions that produce nucleic acid precursors also create the starting materials needed to make natural amino acids and lipids. That suggests a single set of reactions could have given rise to most of life’s building blocks simultaneously.

The technical paper puts it this way:

A minimal cell can be thought of as comprising informational, compartment-forming and metabolic subsystems. To imagine the abiotic assembly of such an overall system, however, places great demands on hypothetical prebiotic chemistry. The perceived differences and incompatibilities between these subsystems have led to the widely held assumption that one or other subsystem must have preceded the others. Here we experimentally investigate the validity of this assumption by examining the assembly of various biomolecular building blocks from prebiotically plausible intermediates and one-carbon feedstock molecules. We show that precursors of ribonucleotides, amino acids and lipids can all be derived by the reductive homologation of hydrogen cyanide and some of its derivatives, and thus that all the cellular subsystems could have arisen simultaneously through common chemistry. The key reaction steps are driven by ultraviolet light, use hydrogen sulfide as the reductant and can be accelerated by Cu(I)-Cu(II) photoredox cycling.

(Bhavesh H. Patel, Claudia Percivalle, Dougal J. Ritson, Colm D. Duffy and John D. Sutherland, “Common origins of RNA, protein and lipid precursors in a cyanosulfidic protometabolism,” Nature Chemistry, March 16, 2015, DOI: 10.1038/NCHEM.2202)

However, I asked an organic chemist who has some experience with these sorts of experiments, and he indicated that their research involves far too much investigator meddling and planning for it to represent unguided natural processes:

I read the article by Patel et al (2015) that appeared in Nature Chemistry. While it is full of fascinating chemistry, given all of the manipulation of pH, precursor mixes, temperature, metal co-ions, etc., it is beyond the pale to pretend that anything in this paper represents undirected pre-biotic chemistry. The only way this paper represents a solution to origin-of-life issues is for Patel et al. to be time travelers who manipulated the pre-biotic environment to produce the building blocks of life. But I am getting ahead of myself.

The Miller-Urey experiment was a great leap forward in the realm of pre-biotic chemistry because they set up an environment that mimicked their best guess as to what the conditions on the early Earth were, flipped the switch to start the electric discharge, and then stood back, getting out of the way of whatever chemistry occurred. While this experiment successfully produced a whole suite of amino acids, essential to building proteins, in all of its variants, they never obtained all four of the RNA nucleobases.

The experiments by Patel et al. fill in this gap but at the cost of a serious amount of investigator intervention. To claim that the whole suite of “precursors of ribonucleotides, amino acids and lipids can all be derived by the reductive homologation of hydrogen cyanide and some of its derivatives” rests on how one defines what are plausible early Earth conditions. By admitting that the products vary depending upon reaction conditions and metallic co-ions, the idea of a one-pot synthesis is not viable in this scenario. They also stretch the concept of “plausibility” to new extreme. While it is easy to imagine a series of pools of the appropriate conditions and with the appropriate precursor compounds all feeding into a single pool, it would be wrong to conclude that what we can imagine is science.

That begs the question of where is the point when randomness ends and intervention by someone or something is the more likely or probable explanation. The fact that any discussion of this issue was omitted from both the paper and its rave reviews in Science Magazine reveals that the paper was written for true believers and not to convince any skeptics.

I have always found the concept of plausibility to be a bit strange. In the range of outcomes from predictable to impossible, my understanding is that plausible is the last stop before impossible:

  • Predictable = one can state with a large degree of certainty the outcome of an experiment.
  • Probable = high probability of a certain outcome.
  • Possible = reaction may happen, if the conditions are just right, but not likely under other conditions.
  • Plausible = you can’t prove that what I am suggesting is impossible so I am going to suggest it no matter how unlikely and improbable it seems. (This is the kind of stuff that only tenured professors can get away with and would be the kiss of death for a graduate student or junior faculty member.)
  • Improbable or impossible = needs no explanation.

So, while plausibility can’t be rejected out of hand, it is also not a situation where one is likely to “bet the farm” on the outcome. Indeed one would be foolish to do so. The fact that this word has played such a major role in the language of pre-biotic chemists since the beginning is an indication of how low the bar of proof is set in the field.

Lastly, looking at the link to the article in Science. Despite the rave reviews and positive comments, one quickly sees that this is merely a puff piece that unquestioningly promotes the article without any critical assessment of its claims.

At the end of the day, as with the Miller-Urey experiment, all we have is a pot of precursor compounds: no amino acid polymers or proteins; no short chains of nucleotides (sugar + base + phosphate) so not even a hint of a start at building an RNA or DNA chain; no long chain fatty acids so no triglycerides or cell membranes. Just a slightly more complete pot of pre-biotic soup. So, sixty-some years after the Miller-Urey experiment, we are just a little bit closer to the complete mix of monomers but not one step closer to building any of the bio-polymers so essential to a working, living cell. Clearly, the title of this article is nothing more than hyperbole.

Indeed, if this mechanism did work then it would seem to be a stroke of incredibly good luck, as even the technical paper admits:

The network does not produce a plethora of other compounds, however, which suggests that biology did not select all of its building blocks, but was simply presented with a specific set as a consequence of the (photo)chemistry of hydrogen cyanide (11) and hydrogen sulfide (12), and that set turned out to work.

Isn’t that fortunate — that the very molecules produced by these chemical pathways “turned out to work.” Moreover, the reactions had to be finely-tuned — they had to have just the right amount of UV light, etc., so as to allow the reactions to proceed forward but prevent degradation of the molecules.

Moreover, all that’s being created here are the precursors to monomers like amino acids and nucleotides. Assuming you could get those monomers, you would have to then form biomolecular polymers RNA and proteins — but forming polymers is a lot more complicated than one might expect. As I explained recently, forming proteins or RNA molecules requires dehydration synthesis — something extremely unlikely to occur under natural conditions:

Assume for a moment that there was some way to produce simple organic molecules on the early Earth. Perhaps they did form a “primordial soup,” or perhaps these molecules arose near some hydrothermal vent. Either way, origin of life theorists must then explain how amino acids or other key organic molecules linked up to form long chains (polymers) like proteins (or RNA).

Chemically speaking, however, the last place you’d want to link amino acids into chains would be a vast water-based environment like the “primordial soup” or underwater near a hydrothermal vent. As the National Academy of Sciences acknowledges, “Two amino acids do not spontaneously join in water. Rather, the opposite reaction is thermodynamically favored.” In other words, water breaks protein chains back down into amino acids (or other constituents), making it very difficult to produce proteins (or other polymers) in the primordial soup.

Materialists lack good explanations for these first, simple steps which are necessary to the origin of life. Chemical evolution is literally dead in the water.

And so the retroactive confessions of ignorance that have accompanied this paper remain, but the “solution” to the problem doesn’t really alleviate our ignorance. It makes the mistake of confusing low probability “possible” events with “plausible” scenarios. Indeed, nothing has been done yet by origin of life theorists to alleviate our ignorance of how to solve the information sequence problem. No wonder biochemist Franklin Harold wrote last year:

Over the past sixty years, dedicated and skillful scientists have devoted much effort and ink to the origin of life, with remarkably little to show for it. Judging by the volume of literature, both experimental and theoretical, the inquiry has thrived prodigiously. But unlike more conventional fields of biological research, the study of life’s origins has failed to generate a coherent and persuasive framework that gives meaning to the growing heap of data and speculation; and this suggests that we may still be missing some essential insight.

(Franklin M. Harold, In Search of Cell History: The Evolution of Life’s Building Blocks (Chicago: University of Chicago Press, 2014), p. 164 (emphasis added).)

Likewise Eugene Koonin wrote in 2011:

The origin of life is one of the hardest problems in all of science, but it is also one of the most important. Origin-of-life research has evolved into a lively, inter-disciplinary field, but other scientists often view it with skepticism and even derision. This attitude is understandable and, in a sense, perhaps justified, given the “dirty” rarely mentioned secret: Despite many interesting results to its credit, when judged by the straightforward criterion of reaching (or even approaching) the ultimate goal, the origin of life field is a failure – we still do not have even a plausible coherent model, let alone a validated scenario, for the emergence of life on Earth. Certainly, this is due not to a lack of experimental and theoretical effort, but to the extraordinary intrinsic difficulty and complexity of the problem. A succession of exceedingly unlikely steps is essential for the origin of life, from the synthesis and accumulation of nucleotides to the origin of translation; through the multiplication of probabilities, these make the final outcome seem almost like a miracle.

(Eugene V. Koonin, The Logic of Chance: The Nature and Origin of Biological Evolution (Upper Saddle River, NJ: FT Press, 2011), p. 391 (emphasis added).)

At the end of the technical paper in Nature Chemistry, we see that it is dedicated to the memory Harry Lonsdale, the late outspoken atheist chemist who, according to a 2011 article for Science Insider, “Scientist-Politician-Atheist Offers Own Money for Origin of Life Prize, offered a $50,000 reward “for the best proposal to study the origin of life and up to $2 million in potential funding to carry out the work.” According to that 2011 article, Lonsdale “hope[ed] that researchers working on the question will eventually prove that life’s origins can be fully explained by physical and chemical processes, without invoking a creator.” If a requirement for winning the prize is that the research must work without “invoking a Creator,” this intelligently designed chemistry experiment published in Nature Chemistry does not seem likely to collect the money.

Image: Precambrian stromatolites, by P. Carrara, NPS [Public domain], via Wikimedia Commons.

Casey Luskin

Associate Director, Center for Science and Culture
Casey Luskin is a geologist and an attorney with graduate degrees in science and law, giving him expertise in both the scientific and legal dimensions of the debate over evolution. He earned his PhD in Geology from the University of Johannesburg, and BS and MS degrees in Earth Sciences from the University of California, San Diego, where he studied evolution extensively at both the graduate and undergraduate levels. His law degree is from the University of San Diego, where he focused his studies on First Amendment law, education law, and environmental law.

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