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A contradiction in Charles Marshall’s “white smoker” origin-of-life argument?


Readers will recall Australian paleontologist Charles Marshall’s argument for horizontal gene transfer between protocells as sparking the origin of life. Anyway, here’s the contradiction, as it appears to Paul Nelson:

Marshall argues (40:10) that the universality of the genetic code, the protein translation machinery (the ribosome, etc.), and other apparently universally shared features of cells, support a scenario in which these features arose within “the same chimney” in an alkaline hydrothermal vent. In other words, we’re back to the single theater model of OOL.

But if the main explanatory attraction of the alkaline vent story is the “massively parallel process” of “hundreds of thousands or millions” (44:00 and following) of OOL theaters in which the RNA World began independently in various localities, then one sacrifices all that probabilistic advantage, and the benefits of horizontal transfer, by reverting to a single chimney to explain the genetic code. “We don’t have to rely on a ‘freak environment’” Marshall says (44:45) “to explain the origin of life.”

Here’s an imaginary dialogue:

Marshall: The universality of the genetic code points unmistakably to a single chimney — one locality where the code first arose.

Skeptic: Why a single chimney?

Marshall: The 64 codon assignments are “ridiculous details” (40:09) — chemically arbitrary.

Skeptic: So these codon assignments would not have happened more than once? Looks like one chimney got lucky.

Thus, unless I misunderstand (always a live possibility), we’re back to postulating a “freak environment,” meaning the OOL explanation is a one-off event after all. The chemical determinism of hundreds of thousands, or millions of alkaline chimneys operating in parallel disappears, and we’re back to one very lucky setting.

Paul Nelson, “Charles Marshall: Origin of Life Could Have Happened “Millions of Times”” at Evolution News and Science Today

Horizontal gene transfer will do a lot but not everything. 64 codons? A lot of freak in thatenvironment.

Meanwhile, the smokers again:

See also: New origin of life thesis: Last Universal Common Ancestor (LUCA) wasn’t actually a cell. Marshall favors horizontal gene transfer as a key method of early development because ancestor–descendant evolution is a “very slow” (42:25) evolutionary process. HGT among multiple independent lineages, by contrast, allows a “vast exchange of information,” thus sharing innovations and leading to faster development. Okay. And in the midst of all that, Dawkins’s Selfish Gene got lost in a crowd somewhere and was never heard from again.

. Ortho is certainly not the first person on UD to state explicitly (or imply) that the gene system is the product of pure chemistry. My issue with Ortho on that particular thread (which originated from a heated exchange between two other participants) is that he claimed, more than once, that the next amino acid bound to a nascent polypeptide is determined by dynamic forces of base pair complementarity. That is flatly incorrect (i.e. it is determined by the physical properties of the aaRS). He begrudgingly conceded that point, then quickly punted away any value to the observation. He asked me why I thought it was important and I gave him the answer - among other things, it helped confirm (along with many other observations) the prediction of a symbol system as the fundamental requirement of the gene system. He had no further comments. Upright BiPed
I thought that the 64 codon assignment to 20 or so amino acids was not "arbitrary", but rather had been shown to be optimal to prevent errors and maintain integrity? Also, while multiple codons code for the same amino acid, they are not acting identically. I read somewhere that there are subtleties and nuances that affect other aspects of the coding. I don't have any references, but it seems a sure bet that the mapping of codons to amino acids is not arbitrary. Fasteddious
Skeptic: So these codon assignments would not have happened more than once? Looks like one chimney got lucky.
Err, no. I think the argument is that they did happen more than once, but then one chimney got lucky and won the Battle of the Chimneys. Basically, selection at the chimney level removes all but one chimney. Bob O'H
marchall: "... the universality of the genetic code, the protein translation machinery (the ribosome, etc.)...." Seversky, JVL & CO ... i have a silly question: What would be a genetic code/ DNA molecule good for without the protein translation machinery (Ribosome and co.) ... martin_r
Marshall: "shared features of cells, support a scenario in which these features arose within “the same chimney”" or, it supports the COMMON ENGINEER/DESIGNER/CREATOR scenario... which is more reasonable to think (thousands of sophisticated molecular machines work together for a purpose, and no-one on Earth was ever even close to re-create these processes in the lab from scratch ) Moreover, after 150 years of Darwinism, there is not a single scientific proof/experiment which confirms spontaneous generation of life. There are only lots of attempts and just-so stories (white smokers, dark smokers, hot vents, cold vents, iron-sulfur lakes, panspermia, and lots of other Darwinian just-so stories ) After 150 years, we look at very desperate Darwinian scientists trying to convince their audience by telling just-so stories about the origin of life ... just-so stories, nothing more... martin_r
There's a simpler argument. The ability to take in and merge incoming genes is a specific talent, a function that needs its own gene. If all the populations were "improved" together by HGT, all the receivers of the improvement would need this function FIRST. And who is carrying the genes during the transfer? Viruses? Other protists? They'd have to be present FIRST. polistra

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