Tuesday, August 11, 2020

Revisiting the Theory Of Abiogenesis (The Origin Of Life) And Why Creationists Hate It

The theory of Abiogenesis (which is often erroneously conflated with the theory of evolution) has been problematical for years. What is sought is a basic explanation for how fundamentally non-living matter could acquire the properties and attributes of life, including being able to reproduce.   For a short video presentation, go to:


In principle this isn't that remarkable a stretch, since we already know there exist living entities at the "margins" - the viruses- which display no attributes of life until they infect a host. Once in a host, they can appropriate its cell machinery to churn out billions of copies of themselves.

All of this, of course, can be done without appeal to supernatural agency.

Enter now an Aussie crackpot named Ken Ham whose Wikipedia profile discloses: "a former president of Answers in Genesis, a creationist apologetics organization that operates the Creation Museum and the Ark Encounter. Ham advocates biblical literalism, accepting the Book of Genesis creation narrative as historical fact and believing the universe and the Earth were created together approximately 6,000 years ago."

Naturally such a bozo would no more be  able to process or accept abiogenesis than Darwinian evolution -   since it renders his biblical cartoon deity redundant.  Moreover, Ham remains upset that Neil deGrasse Tyson dared suggest life on earth started without the help of God, in one COSMOS episode years ago. All Tyson did is honestly state that the very origins of life “are not yet understood”. Because abiogenesis has yet to turn up any verifiable results—not that they have claimed any are verifiable—AiG is calling that evidence of a clear flaw. But what’s clear is that Tyson isn’t just a threat to creationists. Their big target is the reputation of science.

AiG  seeks to discredit the underlying biological science, using this standard trope:

Abiogenesis has never been observed in experimental biology and violates the most fundamental law in biology, the law of  biogenesis. Nevertheless, the authors of the review are confident there was a naturalistic chemical origin for life.” [Biogenesis is the natural law that life comes from reproduction by living things].

However,  in a remarkable find published in The New Scientist (Vol. 209, No. 2794, p. 11) some years ago, two investigators: Kunikho Kaneko and Atsushi Kamimura, made a remarkable breakthrough in devising a testable model that is able to replicate the Abiogenesis process. The two basically solved the problem of how a lipid-coated proto-cell can divide into two (displaying reproduction) when the genetic material replicates. Recall in an earlier blog post where I showed the hypothetical proto-cell reaction wherein a self-sustaining coacervate droplet can use one or two basic reactions involving adenosine triphosphate (ATP) and adenosine diphosphate:

L*M + R + ADP + P -> R + L + M + ATP

ATP + X + Y + X*Y -> ADP + X*Y + X*Y + P

In the above, L*M is some large, indeterminate, energy-rich compound that could serve as ‘food’. Whatever the specific form, it’s conceived here to have two major parts capable of being broken to liberate energy. Compound R is perhaps a protenoid or lipid-coated proto-cell, but in any case able to act on L*M to decompose it. The problem with this earlier hypothesis was that such lipid-coated proto-cells lack the machinery to allow for easy division.

Kaneko and Kamimura solved this by taking their inspiration (for their model) from living things in which DNA and RNA code for proteins and the proteins catalyse replication of the genetic material. This goes back to biochemist Jacque Monod's concept that the organism is a self-constructing machine. Its macroscopic structure is not imposed upon it by outside forces, instead it shapes itself autonomously by dint of constructive internal (chemical) interactions. 

 For example, there is the Krebs cycle for aerobic metabolism, whose pathway  is:

CH2 COOH-coenzyme A +  2 H2O ->   2 CO2  +8 (e- + H+) + coenzyme A

possessing a self-catalytic feature in that intermediate products necessary for the cycle to occur are generated by the cycle itself. In this case, Oxalo-acetic acid combines with acetic acid to begin the cycle and is regenerated from malic acid at the end of the cycle.

Like a machine, every organism, down to the very ‘simplest’ (e.g. amoeba) , constitutes a coherent and integrated functional unit. Clearly enough, the functional coherence of so complex a chemical machine, which is autonomous as well, calls for a cybernetic system governing and controlling the chemical activity at numerous points

 Thus in the Kaneko- Kamimura model one has a self-perpetuating system in which a cluster of two types of molecules catalyse replication for one another while also demonstrating rudimentary cell division.

In the Kaneko - Kamimura  (K-K) model, as with DNA, the genetic material replicates much more slowly than the other cluster molecules but also takes longer to degrade, so it enables lots of the other molecules to accumulate. Following replication of the heredity carrier the copies drift apart while the molecules between them break down automatically creating two separate entities (see image).

This was  and remains an exciting breakthrough but some further investigations are needed, specifically ways to circumvent the problem that (in real life) membrane lipids around an RNA molecule don't typically catalyse RNA replication. However, this isn't insurmountable, because all one need do (theoretically) is replace the lipids with hydrophobic peptides.  (In a future post I will explore how modern physics is helping to address this problem).

Basically what the K-K experiments show is that while abiogenesis hasn’t been directly observed it does provide  a materialist model that can account for it in a peripheral way. Since such a materialist model exists, it means that all supernatural explanations become redundant. If one therefore continues to use them, he commits the fallacy of ignotum per ignotius.  That is,  “seeking to explain the not understood by the less well understood.”

Thus to claim abiogenesis “has not been observed” (directly) – which is partially true, and then to say this proves the creation story -  is something that would even raise the eyebrows of an intelligent  kindergartner . Indeed it not only commits the fallacy of ignotum per ignotius, but also the fallacy of circular reasoning – since AiG and Ham are basically claiming that which they must set out to prove independently. Even if nothing existed for abiogenesis, they would be obliged to prove supernatural creation.   It simply isn't cricket to try to use a naturalistic failure (in their mind) as positive “evidence” for their extraordinary claim.

More importantly the AiG claim that abiogenesis  “breaks the law of biogenesis”  is dishonest. The law of biogenesis (attributed to Louis Pasteur)  states that life cannot come from non-life, but Pasteur did not demonstrate that any such impossibility- only that it does not happen in everyday life. As shown in the K-K model it is at least possible that such can take place.

Now, add to that the Miller-Urey experiment. The Miller and Urey experiment basically applied an electrical discharge to a chemical brew resembling the Earth’s primitive reducing atmosphere. This brew included ammonia and methane, as well as hydrogen and water vapor. The effect of the discharge transformed the mix into a diverse yield of organic compounds. These included amino acids, as well as substances such as formic acid and urea that normally occur in living organisms.

The very fact so many organic compounds could arise is remarkable in itself, given the vast number of possible compounds that might have emerged. And while it is true that the discharge didn’t produce actual living cells, there is no reason – given enough time,- that a primitive pre-biotic cell in the distant past could not have emerged given the building blocks left behind

None of this was mentioned by Tyson, but it could have been and would likely have made the creationist crowd's heads explode even more.  Never mind.  In that memorable COSMOS episode Tyson gave  viewers a naturalist’s explanation for the world, and when he said science does not yet know something, that was no concession  of the failures of science, but instead a powerful example of the necessary honesty in which science thrives.

 That AiG sees the words “I don’t know” as a weakness shows the lengths of intellectual dishonesty they are willing to invoke to pull the wool over their followers’ eyes. (Though again, Tyson also could have shown more support for abiogenesis – such as by invoking  the Miller-Urey experiment- to make this less likely.)

No absolute proof yet for abiogenesis?  No  problem!  We atheists will take what we can get incrementally -  and if a naturalist universe can be delivered easily,  in bite- sized pieces by an affable showman like Neil Tyson-   so much the better.  

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