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Saturday, 7 October 2017

For OOL science the show must go on.

Cheaters Never Prosper? Sure They Do in Origin-of-Life Papers
Evolution News @DiscoveryCSC

Today we’re going to look at some recent papers about the origin of life and make some perhaps surprising observations: (1) some of their ideas are demonstrably false, and (2) other ideas cannot possibly be true. Why do the journals let them get away with it? Here’s why: there is no such thing as a sensible materialistic theory for the origin of life, and the one-party rule in science gives them cover. In a world governed by materialism, the only criticisms allowed must also be materialistic. This guarantees absurdity will continue to rule the field.

Fortifying the Soup with a Pinch of Design

Here’s your National Science Foundation at work. Research news from  Georgia Tech, thanks to funding from the NSF/NASA Center for Chemical Evolution (paid by taxpayer dollars, in other words), asks: “Was the Primordial Soup a Hearty Pre-Protein Stew?” That one is a gem. Then, mixing his metaphors, reporter Ben Brumfield feeds his hearty stew to the Darwin dancers: “The evolutionary path to first proteins may have been paved with relatively easy, small square-dance steps.” 

Hype aside, Brumfield admits that “Scientists have long puzzled over how the very first proteins formed. Their long-chain molecules, polypeptides, can be tough to make in the lab under abiotic conditions.” Previous yields have been modest, he confesses. But now, with assurances from Georgia Tech faculty that they will stick to only realistic early-earth scenarios, he cooks up “pre-protein stew” made of depsipeptides — short chains of amino acids shorter than polypeptides — that he presents as stepping stones to real proteins, provided they get a little help from esters and hydroxy acids, and are submitted to convenient cycles of wetting and drying.

A look at the paper in  PNAS shows how they fudged. They started with only left-handed amino acids! This stacked the deck at the outset, without any justification. They also ignored the innumerable damaging cross reactions that would have overwhelmed any useful molecules. Then they skirted around the sequencing problem, even though the paper makes it clear they are fully aware of the fact that sequence space vastly exceeds usable protein space, as Doug Axe has made clear in his papers (referenced in his book,  Undeniable).

One of the most daunting challenges associated with this question is the inherent vastness of proto-peptide sequence space, which may be many orders of magnitude greater than that of peptides encoded by genes in living cells. If a model prebiotic pool of only 10 amino acids and 10 hydroxy acids is considered, and equal monomer reactivity is assumed, the potential number of depsipeptide sequences with length 10 would be (10 + 10)10, or ∼1013. As a result of this staggering number, progress on the characterization of plausibly prebiotic amino acid pools, abiotic mechanisms for peptide self-assembly, and the evolution of early ribosomes has not been paralleled by a systems-level understanding of proto-peptide diversity.

But rather than buckle under that fact, they decided to play with sequences of four amino acids. That’s right: four. Knowing that the problem mushrooms the longer the sequence, they extrapolated their hope far beyond just four peptides (tetramers).

The observation of more diverse tetramers as the system evolved is consistent with the hypothesis that a vast array of sequences may have been present on the prebiotic earth before the initiation of template-directed peptide synthesis.

Did they find that unguided natural laws honed in on the tiny subset of useful sequences? No. They just assumed that the more random sequences, the better. Does that make any sense? Do more haystacks produce more needles? Even if they did, will the needles get together on an earth-sized soup? Will a part in a pond in Africa find its matching part in South America? Will matching parts be produced at the same time? For polypeptides long enough to have biotic significance, it would be outrageous to think so. Both William Dembski and Doug Axe have treated navigating sequence space as a search algorithm. Without intelligent design in the form of an independently supplied treasure map, no evolutionary algorithm is superior to blind search. This implies that tetramers have no better way of locating a useful protein sequence than does pure chance. (For that improbability, see Illustra’s amoeba illustration from the film Origin.)

Consider their sentence, “a vast array of sequences may have been present on the prebiotic earth before the initiation of template-directed peptide synthesis.” Whoa! Stop right there! What is “the initiation of template-directed peptide synthesis”? Where did that come from? They’re talking about genetic codes! Transcription machinery! Transfer RNAs! Messenger RNAs! Ribosomes! Words fail to describe the hurdles those things present for naturalism. The researchers know this, but evidently didn’t complain when their university’s press office put out misleading metaphors about “hearty pre-protein stew” and how “The evolutionary path to first proteins may have been paved with relatively easy, small square-dance steps.”

Boring Boron

Let’s take a brief look at another example of fudging by federally funded labs doing origin-of-life research. “Discovery of boron on Mars adds to evidence for habitability,” promises the Los Alamos National Laboratory. In this case, instead of proteins, they’re trying to build RNA or DNA, which use complex sugars.

The subtitle reads, “Boron compounds play role in stabilizing sugars needed to make RNA, a key to life.” Strange as it seems, the Curiosity rover found a chemical element on the red planet. Who would have thought? Life must be coming right up in the Mars kitchen! The hopeful headline conceals the desperation origin-of-life chemists have suffered trying to get ribose to form and survive under plausible prebiotic conditions.

RNA (ribonucleic acid) is a nucleic acid present in all modern life, but scientists have long hypothesized an “RNA World,” where the first proto-life was made of individual RNA strands that both contained genetic information and could copy itself. A key ingredient of RNA is a sugar called ribose. But sugars are notoriously unstable; they decompose quickly in water. The ribose would need another element there to stabilize it. That’s where boron comes in. When boron is dissolved in water — becoming borate — it will react with the ribose and stabilize it for long enough to make RNA.

The research is published (open-access) in Geophysical Research Letters. Like the first paper, this “scenario” relies on wet-dry cycles to work magic. But since they don’t even consider how peptides could have formed, there’s an even greater time and distance problem here. Granting them the most inconceivably generous latitude to assume that ribose did form, and then RNA, and then DNA, how would they get those parts to earth to work on the peptides? Or how would the proteins get to Mars? It’s ridiculous to think that Mars “may” have been habitable just because the rover found some boron in Gale Crater.

On Mars, we have shown borate was present in a long-lived hydrologic system, suggesting that important prebiotic chemical reactions could plausibly have occurred in the groundwater, if organics were also available. Thus, the discovery of boron in Gale crater opens up intriguing questions about whether life could have arisen on Mars.

We couldn’t find any units, definitions, or numbers on their “plausibility” scale. Many of the same hurdles exist in this scenario. How did unguided causes select only one-handed sugars? How did the bases, even if they formed, arrange themselves into the tiny fraction of functional sequences out of an extremely vast sequence space? How did they become associated with polypeptides, such that protein machines “took over” the transcription and translation function? The conceptual and experimental difficulties glossed over in these two papers are numerous, egregious, and insurmountable.

The two papers remind one of the joke about a hobo cheering up his hungry buddy, saying, “If we had ham, we could have ham and eggs, if we had eggs.” The buddy’s hunger will not be satisfied if the friend promises, “I might be able to get some ham (or eggs).” “Really? Got any?” “Not yet, but I’m working on a scenario to get some.” “Like what?” “Well, I figure if I put these pebbles in a puddle and let them get wet and dry over a few years, I imagine that some building blocks of pre-ham or pre-eggs might emerge someday.”

Onward but Not Upward

One more example. Again, in PNAS, with government support from the U.S. Department of Energy, researchers assume the myth of progress. Simple things will climb the ladder to elegant systems, won’t they? This paper presents the “Foldamer hypothesis for the growth and sequence differentiation of prebiotic polymers.” Basically, they try to leapfrog over the sequence-space hurdle with little steps. Notice their trust in the myth of progress:

Today’s lifeforms are based on informational polymers, namely proteins and nucleic acids. It is thought that simple chemical processes on the early earth could have polymerized monomer units into short random sequences. It is not clear, however, what physical process could have led to the next level — to longer chains having particular sequences that could increase their own concentrations. We study polymers of hydrophobic and polar monomers, such as today’s proteins. We find that even some random sequence short chains can collapse into compact structures in water, with hydrophobic surfaces that can act as primitive catalysts, and that these could elongate other chains. This mechanism explains how random chemical polymerizations could have given rise to longer sequence-dependent protein-like catalytic polymers.

These researchers, too, know that “sequence spaces grow exponentially with chain length,” leading to the admission that, “Therefore, those few particular special sequences would wash out as biology moves into an increasingly larger sequence space sea.” To overcome this hurdle, they appeal to imagination, supposing that little folds will accumulate into the large, complex folds we see in real proteins.

Our goal here has not been to consider the evolution of functionalities beyond “ribosome-like chain elongation,” but ensemble models, such as this one, would lead to many other potential functionalities.

Real functionalities? No; “potential functionalities.” Their model “aims to capture a few principles in a coarse-grained way,” held together by copious amounts of imagination and faith.

Even so, the sorts of actions suggested here are currently more in the realm of speculation than proven fact. Below, we describe results of computer simulations that lead to the conclusion that short random HP chains carry within them the capacity to autocatalytically become longer and more protein-like.

What they don’t realize, though, is that there’s no free lunch. The “No Free Lunch” theorems that Dembski explicates in his book of that name guarantee that no search algorithm (such as their foldamer hypothesis) is superior to blind search. Without intelligence, there’s no way to improve on sheer dumb luck.

Conclusions

When we point out the flaws in materialistic scenarios like this, a common response is that we must be resorting to god-of-the-gaps. Isn’t lab research better than sitting back and saying, “God did it” whenever we encounter a problem?

Actually, the shoe is on the other foot. We have good reason to embrace the alternative, intelligent design. Whenever we find complex systems of functional, hierarchical, coded information where we have the opportunity to observe the system come into existence, we always find intelligence as the source. The Law of Uniformity justifies our approach in considering intelligence as the vera causa of the systems in life, which dramatically exceed in purposeful complexity anything humans have ever designed. Intelligence is a cause we know. It is necessary. It is sufficient. The rational response is to appeal to intelligent causes, not to arbitrarily rule them out a priori.

By contrast, working against the known laws of chemistry and probability in order to maintain a philosophical preference is anti-scientific. The only way to claim progress is to play games, as these three instances show: speculating, imagining, and hyping. In essence, they commit materialism-of-the-gaps to bridge huge chasms that keep growing wider with each new discovery about the complexity of life.


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