Before I write about what the thermal vents theory presented, I would like to point out that this theory is far from agreed upon within the evolutionary community. In fact, origins is still a hot topic among evolutionists and there are many different theories out there competing for the prize, so to speak. Furthermore, this particular variant of the thermal vent theory is only one of several. If this theory was so solid, then everyone would agree on it. They do not.
This comment shows ignorance of what the scientific method is all about. Creationists often pounce on scientists for disagreeing about a theory, when such disagreement is at the heart of true science. Origin-of-life theory is a hot topic right now in science; as mentioned, there are several competing theories.
This is not a drawback of science. It is how science operates. It evolves- it gets better and more accurate as more information is discovered and incorporated into theories. Theories that don’t work get thrown out. Lack of agreement on a theory in no way invalidates it- only scientific evidence against it can do so.
And next, regarding Yockey. Isn't there another possibility? Can there be a chance that I'm not either dishonest or misinformed? What could I possibly be referring to? Oh, right. The fact that he is one of several scientists who hold to the idea of an old Earth AND a Designer. A creationist is someone who holds to a literal 6-day creation. We do differentiate. You also have an amazing ability to twist what I say or disfigure and misrepresent the creationist position. To that, I say that you should read what I write more carefully or be more honest. You have done this several times and I will deal with each one as I write the posts on various topics. Did I say Yockey was a "non-biased source?" NO! There is no such thing when it comes to origins which I treated in great detail. Maybe you didn't read it thoroughly. Origins deals with the unobservable, unrepeatable past. As such, one must have a preexisting bias toward a particular theory. Evolutionists prefer long ages and Christians hold the idea of a Creator. The question is interpreting the evidence we have which is what our discussion is about. Before you accuse me of dishonesty or misinformation, you better make sure that you have correctly understood what I wrote. I will call it out every time. Dr. Yockey is no friend to creation science and yet he still recognized the validity of the probability argument. That is why I chose the quote. He is not alone. I will treat probability again in another post.
The point still stands. Yockey is a biased observer; his word cannot be taken as impartial. As to the differentiation you attempt to make between various types of non-scientific belief systems regarding the origin of life- they are summed up very well by a quote from Leonard Krishtalka, director of the Natural History Museum at the University of Kansas-“Intelligent design is creationism in a cheap tuxedo.” As to “A creationist is someone who holds to a literal 6-day creation”- really? What about old-earth creationists, day-age creationists, gap theory creationists…
Let's take a closer look at thermal vents.
I wish that we would. Unfortunately, you don’t.
First of all, the theory of thermal vents posted here is not enough in and of itself.
I never claimed that it was. It is one small part of one possible mechanism for the evolution of complex organic molecules.
The following quote is from article at http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030396&ct=1.
"This metabolism-first model is not an alternative to life based on RNA. “We can't work without an RNA world either,” says Martin. But it does propose that geology at hydrothermal vents provided the structure in which life emerged, and suggests that understanding prebiotic organic chemistry at these vents may provide the key to understanding the emergence of life from nonlife."
I am baffled by the purpose of this quote. No one- including myself- posits that thermal vents are the only mechanism. And, as this quote clearly states, “understanding prebiotic organic chemistry at these vents may provide the key to understanding the emergence of life from nonlife.”
You asked me if I think acetates can form on an iron-sulfur substrate. Probably. But this has little to do with adenine, uracil, guanine or cytosine.
“You ask me if silicon can be smelted into glass. Probably. But that has little to do with strawberry jam, Kool-Aid, strawberry shortcake or Neopolitan ice cream.” You’re avoiding the question. No one thinks that RNA formed from nothing. There is no such theory. And thermal vent theories are very specifically not about RNA.
There are, broadly, two different realms of theories for the formation of the first complex organic molecules- RNA-first (as the paper you quote is concerned with) and metabolism-first (the theory I was discussing in my post) They are totally different (although not incompatible!) theories.
I will back up for a second.
You aren’t backing up. You are introducing a completely different topic. This is not a discussion of RNA-first theories.
Many evolutionists favor the "warm little pond" origin-of-life theory or the thermal vent theories because they postulate that the oldest known organisms are hyperthermophiles that would have required temperatures between 80 and 110 degrees Celsius.
A major problem for any of these theories is that adequate concentrations of certain complex compounds necessary for life are not accounted for. There has to be a requisite level of stability so that synthesis is at higher levels than degradation. What you proposed is an attempt to cover for these lacking components. By saying that those chambers function like cell walls is overly simplistic to say the least. While the vents you speak of may themselves be more stable (the one article mentioned they'd be stable for thousands of years...this is highly argumentative to say the least), we haven't yet touched the biggest problems with this proposed model. They have also been highly criticized because experimental research has shown that the half-lives of many vitally important compounds to be “too short to allow for the adequate accumulation of these compounds” (Levy and Miller, 1998, p. 7933)."
Once again- RNA-first and metabolism-first scenarios are totally different. Levy and Miller’s research has nothing whatsoever to do with metabolism-first theories. If anything, it actually supports such theories!
Levy and Miller go on to say that, "“unless the origin of life took place extremely rapidly (in less than 100 years), we conclude that a high temperature origin of life... cannot involve adenine, uracil, guanine or cytosine” because these compounds break down far too fast in a warm environment. In a hydrothermal environment, most of these compounds could neither form in the first place, nor exist for a significant amount of time (Levy and Miller, p. 7933)." They continue, "the rapid rates of hydrolysis of the nucleotide bases A,U,G and T at temperatures much above 0° Celsius would present a major problem in the accumulation of these presumed essential components on the early earth” (p. 7933). Below is the website:
http://www.pnas.org/cgi/content/abstract/95/14/7933
You are showing a grave misunderstanding of the theory I am discussing. I don’t think you actually read the article you quoted from above, other than to pull an out-of-context unexplained quote from it. Once again- this theory is not about the evolution of RNA. It’s about the evolution of metabolic cycles before RNA. The article you discuss is totally irrelevant to this theory.
Can you please stick to the topic at hand and respond specifically to this article?
As a result of this, they theorized that either a two-letter code or an alternative base pair was used instead. This has the distinction of demanding an absolutely different kind of life was formed. This is not only highly speculative, but likely impossible because only A, U, G and T have the requisite properties for life. So now, life would have had to evolve completely differently than we know it today, and then re-evolve into the known code of life we see today. This change, by the way, appears to be impossible based on current knowledge of molecular biology.
And lastly, the authors found that given the minimum amount of time needed for evolution, cytosine is unstable even at temperatures as cold as 0 degrees Celsius. If Cytosine is lacking, then it is impossible to have DNA. It is also impossible to have RNA.
Again, the main thing that your argument does is strengthen the case for metabolism-first theories such as the one I discussed. You also have some misunderstandings and misrepresentations of the research. For example, the authors gave several possible theories of how nucleobases could have developed; some of which are possible at higher temperatures. The main point of this article is to present a theory that the nucleobases probably developed in frozen oceans rather than in a greenhouse atmosphere.
In addition, in the almost ten years since this paper was published, many theories have arisen that could allow development of nucleic acids in a prebiotic world- the PNA (favored by Levy and Miller) GNA and TNA , -first hypotheses and the PAH-first hypothesis . These theories can also explain the origin of self-replicating molecules at higher temperatures.
For a related source, see below:
http://www.creationresearch.org/crsq/articles/36/36_4/abiogenesis.html
Interesting. I had never heard of the author, “Jerry Bergman, PhD” or of his college, “Northwest State College.” A little research showed that Bergman probably shouldn’t be using the term “PhD”- In 1992 Bergman received his Ph.D. in human biology from Columbia Pacific University, a now defunct nonaccredited distance learning school. Columbia Pacific University lost its state approval to operate in 1995 and was ordered to close permanently in October 2000 by the State of California.
In another incident, he lied to the staff at Bowling Green State University, claiming he had a PhD when he did not. When he was fired for this and other ethical improprieties, he responded with a flurry of lawsuits complaining of “religious discrimination”- all of which he lost, in four different venues.
Of course, we cannot base our evaluation of the material in this article on his personal shortcomings- facts can be judged only on their own merits. As for the article - it’s typical creationist claptrap, composed almost entirely of quote mining, with no original research whatsoever. All of the points made in this article have been refuted many times, (check the Index to Creationist Claims as a start)
In conclusion, the thermal vents theory speculated on is nowhere near as strong as presented and it is clearly seen why not everyone in the evolutionary community is ready to jump on board.
You never discussed the thermal vent theory. The entirety of your comment on it was the word “Probably.” You discussed a totally different theory.
We also have the problems of the Second Law of Thermodynamics and probability. These will be treated again in other posts.
‘If there were a basic principle of matter which somehow drove organic systems toward life, its existence should easily be demonstrable in the laboratory. One could, for instance, take a swimming bath to represent the primordial soup. Fill it with any chemicals of a non-biological nature you please. Pump any gases over it, or through it, you please, and shine any kind of radiation on it that takes your fancy. Let the experiment proceed for a year and see how many of those 2,000 enzymes [proteins produced by living cells] have appeared in the bath. I will give the answer, and so save the time and trouble and expense of actually doing the experiment. You would find nothing at all, except possibly for a tarry sludge composed of amino acids and other simple organic chemicals. How can I be so confident of this statement? Well, if it were otherwise, the experiment would long since have been done and would be well-known and famous throughout the world. The cost of it would be trivial compared to the cost of landing a man on the Moon… . In short there is not a shred of objective evidence to support the hypothesis that life began in an organic soup here on the Earth.’
Sir Fred Hoyle, British physicist and astronomer, The Intelligent Universe, Michael Joseph, London, 1983, pp. 20-21, 23.
I should add that Sir Fred Hoyle was a proponent of 'intelligent cosmic control.' This quote is very much in line with the context.
Again, this quote has absolutely nothing to do with the theory that I am discussing.
I also hope you do realize that science is not a quote contest. A quote by itself is meaningless and proves nothing. Instead, one must look at several factors- who said the quote, is that person an authority on the subject, are that person’s views being represented fairly and completely, and (perhaps most importantly) how does the scientific community as a whole regard that person’s words and work?
Hoyle’s quote fails here on several counts. He was not a biologist or chemist; he was an astronomer. His pronouncements on biochemical theories are thus no more authoritative than a chemist’s speculations on whether Pluto is a planet.
As for his authority- he was well-known for clinging to theories that had no real backing. Creationists often claim that scientists cling tenaciously to outdated and disproven theories even in the face of massive evidence against them. While this is not true of scientists as a whole, it was true of Hoyle.
In the end, mounting observational evidence convinced most cosmologists that the steady state model was incorrect and that the Big Bang was the theory that agreed best with observations, although Hoyle clung to his theory, mostly through criticizing the interpretation of astronomers' observations. In 1993, in an attempt to explain some of the evidence against the steady state theory, he presented a modified version called "quasi-steady state cosmology" (QSS), but the theory is not widely accepted.While creationists delight in quoting Hoyle’s words on abiogenesis, they neglect to tell the full story behind his remarks- he was an atheist and believed that life on Earth originated from material such as bacteria, viruses and insects spread by comets and interstellar debris, perhaps intentionally by intelligent extraterrestrial beings. As for his specific arguments against abiogenesis, they have been refuted so often that they are known as “Hoyle’s fallacy.”
The evidence that resulted in the Big Bang's victory over the steady state model, at least in the minds of most cosmologists, included the discovery of the cosmic microwave background radiation in the 1960s, the distribution of "young galaxies" and quasars throughout the Universe in the 1980s, a more consistent age estimate of the universe and most recently the observations of the COBE satellite in the 1990s, which showed that unevenness in the microwave background in the early universe which corresponds to currently observed distributions of galaxies.
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