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:: Friday, March 18, 2005 ::
Response Research, Part I
::This post is part of the Evolution/ID Correspondence Series::
Because Doug the creationist cited an article on a creationist web site, THE MYTH OF CHEMICAL EVOLUTION, by a Dr. David Rosevear. Rosevear is a "creation scientist," and purportedly a chemist, but a Google Scholar search for his name shows no publications at all of his in any peer reviewed journals. If his work hasn't passed peer review, it is not sound research, period. The author's credibility is, as such, in question from the start.
Rosevear starts by spouting some nonsense about spontaneous generation and miststates pasteur's findings, especially since Pasteur's experiment didn't run for hundreds of millions of year, and neither did it even try to replicate the conditions of the primordial earth.
Rosevear cites the people who laid the foundations for the modern understanding of the origins of life as communists. Sound scientific findings are respectable and considered true no matter what one's ideologies are because the Scientific Method doesn't allow ideology to enter into it. By specifically calling them communists and implying that they were colluding together, Rosevear is making an ad hominem attack, further discrediting his position.
Lynn Margulis has suggested that the first proto-cell assimilated these organelles by a process of symbiosis. However, these components cannot now exist independently, nor could the cell exist without their contributions. Moreover, one such type of organelle, known as a lysosome, contains enzymes whose function is to digest foreign bodies. With all the amazingly complex, mutually-dependent components, it seems that the cell had to be complete from the beginning, rather than being assembled piecemeal over years of evolution.
This is a false conclusion. Just because this is how things are now, doesn't mean that this is how they always were. Mitochondria and Chloroplasts both have their own, separate DNA and replication machinery, and some Chloroplasts can live independent of their parent cells. These are the organelles for which symbiosis is the most obvious. The other organelles have less strong arguements associated with them, but their origins will be either traced to sybiosis or to novel constructions of the parent cell. In any case, Rosevear has failed to discredit endosymbiotic theory.
The major biochemicals in living cells are proteins and nucleic acids. No biologically significant proteins or nucleic acids have been made by any experiments such as those of Miller or those who have followed him.
Proteins are a red herring, since they are assembled by ribosomes (themselves catalytically active RNA strands) from ammino acids, which were produced by Miller's experiment). As for nucleic acids, there is evidence to suggest that RNA itself may not have been the first genetic material: as described by Leslie Orgel in Science, Vol 290, Issue 5495, 17 Nov 2000, "A Simpler Nucleic Acid," other RNA analogs, that are able to be easily synthesized from two-carbon compounds, are known to molecular biology. These pre-RNAs may have had different configurations, but were able to aneal (base-pair) with RNA in a double-helix, just like RNA can with DNA and DNA can with itself. Admittedly, this article was published after Rosevear's, but Rosevear's arguement falls nonetheless.
Not all amino acids found in proteins can be synthesized in this manner, while many not used by living systems do result from these experiments. A product consisting of exclusively left-handed amino acids never results, and from theoretical considerations cannot result. Only d/l racemic mixtures are formed.
So? Biological catalysts are stereoselective, in that only a D or L substrate is used or created via a mechanism catalyzed by a specific enzyme/ribozyme, never both. The inclusion/creation of further L-amino acids by such stereoselective biological catalysts easily explains the current stereochemical bias in living systems.
Rosevear forgets short nuclear RNAs (snRNAs), intentionally leaving out vital evidence for the RNA World hypothesis.
No mutation could lead to an increase of information, so neo-Darwinism cannot be a mechanism for macroevolution.
I've refuted this previously. As a result, the "Information Theory" stuff that follows has no grounds to stand on.
When nucleotides are joined in the laboratory, thermodynamic considerations allow one particular site for bonding phosphate to sugar to the next phosphate. However, such a pseudo-DNA strand is not biologically useful. The bonding site found in DNA, the 3¢ and 5¢ carbons of ribose, is in the best position because the proteins used to join it together act as templates to get the junction across the sugar right. The sugars, deoxyribose in DNA, and ribose in RNA, are also chiral like the amino acids, but in this case the sugars are all right-handed. Again, there is no conceivable mechanism for arranging this by chance.
See above for the chirality bit. "[S]uch a pseudo-DNA strand is not biologically useful" is not substantiated.
Urey and Miller had to assume, contrary to the opinions of geologists, that the early Earth had no oxygen in its atmosphere.
Thing is, they were right - and I find the phrase in apposition to be specious, since Miller based his understanding of the early atmosphere on the current consensus. Rosevear needs to back up his claim.
The tarry messes from these experiments are in stark contrast to the neat metabolic pathways of living cells with their clean, high yields of precisely fashioned products.
Rosevear makes a misstatement of fact - the point of Miller's experiment was merely to create raw organic materials from chemicals and conditions then thought to be present. That the "tarry mess" didn't wasn't the product of "neat metabolic pathways" wasn't the point and doesn't detract from Miller's findings.
The problem of the origin of information on the information carrying RNA remains unsolved.
Nope, see above.
And about ATP syntase... ATP is not the only energy-carrying molecule in the cell, and it wasn't necessarily the first - other, simpler molecules could have carried out this task, while ATP synthase was either cobbled together from elements from another system OR was simply an existing system repurposed. (In fact, as bacteria - those organisms from which mitochondria are descended - have flagella that rotate, ATP synthase could have originated as a flegellar system that utilized the proton gradient set up by another protein like rhodopsin to spin. The ability to use/catalyze ATP to ADP and vice-versa could've come later, with the external flagella being lost over time as the system was repurposed.) This is not incompatible with evolution.
Also, Rosevear's motor analogy is inaccurate - the "rotor" action merely causes the ATP to be kicked out of the active sites, allowing ADP to come in and be phosphorylated.
Rosevear is guilty of the same logical fallacy as all who support Irreducible Complexity, namely argumentum ad ignorantium. Instead of trying to reason out how such systems came to be, Rosevear just looks at them, throws his hands up in the air, and says, "It's not immediately apparent, therefore it must be the direct work of God."
The long and short of all this is that Rosevear claims that "chemical evolution" is a myth, but fails horribly at the task of proving his assertion. Because his essay is so horribly riddled with errors, I have no choice but to ignore his arguments.
:: The Squire 12:15 AM :: email this post :: ::
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