Posted on 11/02/2003 10:30:46 AM PST by PatrickHenry
"Isn't life wonderful?" sang Alma Cogan and Les Howard in their almost forgotten 1953 hit. That same year, Stanley L. Miller raised the hopes of understanding the origin of life when on 15 May, Science published his paper on the synthesis of amino acids under conditions that simulated primitive Earth's atmosphere (1). Miller had applied an electric discharge to a mixture of CH4, NH3, H2O, and H2--believed at the time to be the atmospheric composition of early Earth. Surprisingly, the products were not a random mixture of organic molecules, but rather a relatively small number of biochemically significant compounds such as amino acids, hydroxy acids, and urea. With the publication of these dramatic results, the modern era in the study of the origin of life began.
Since the late 19th century, the belief in a natural origin of life had become widespread. It was generally accepted that life's defining properties could be understood through physico-chemical characterization of "protoplasm," a term used to describe the viscous translucent colloid found in all living cells (2). Expressions like "primordial protoplasmic globules" were used not only by scientists but also in fiction, from Gilbert and Sullivan's Pooh-Bah in The Mikado (1885) to Thomas Mann's somber imaginary character Adrian Leverkühn in Doktor Faustus (1947). But few dared to be explicit, even in novels. Questioned about the origin of life, a chemist in Dorothy L. Sayers' novel The Documents in the Case (1930) states that "it appears possible that there was an evolution from inorganic or organic through the colloids. We can't say much more, and we haven't--so far--succeeded in producing it in the laboratory."
Some were willing to fill in the details. At the turn of the 20th century, many scientists favored the idea of primordial beings endowed with a plant-like (autotrophic) metabolism that would allow them to use CO2 as their source of cellular carbon. However, some scientists--including A. I. Oparin, J. B. S. Haldane, C. B. Lipman, and R. B. Harvey--had different ideas (3). The most successful and best-known proposal was that by Oparin, who, from a Darwinian analysis, proposed a series of events from the synthesis and accumulation of organic compounds to primordial life forms whose maintenance and reproduction depended on external sources of reduced carbon.
The assumption of an abiotic origin of organic compounds rested on firm grounds. In 1828, F. Wöhler had reported the first chemical synthesis of a simple organic molecule (urea) from inorganic starting materials (silver cyanate and ammonium chloride).
After a large body of research on the synthesis of simple organic compounds accumulated in the 19th century (see figure above), W. Löb achieved the chemical syntheses of simple amino acids such as glycine by exposing wet formamide to a silent electrical discharge and to ultraviolet light (4).
These efforts to produce simple organic compounds from simple reagents heralded the dawn of prebiotic organic chemistry. However, there is no indication that the scientists who carried out these studies were interested in how life began on Earth, or in the synthesis of organic compounds under possible prebiotic conditions. This is not surprising, because the abiotic synthesis of organic compounds was not considered to be a necessary prerequisite for the emergence of life.
From the 1950s, chemists were drawn toward the origin of life. Driven by his interest in evolutionary biology, Melvin Calvin tried to simulate the synthesis of organic compounds under primitive Earth conditions with high-energy radiation sources. He and his group had limited success: the irradiation of CO2 solutions with the Crocker Laboratory's 60-inch cyclotron led only to formic acid, albeit in fairly high yields (5). Miller's publication 2 years later showed how compounds of biochemical importance could be produced in high yields from a mixture of reduced gases.
The origin of Miller's experiment can be traced to 1950, when Nobel laureate Harold C. Urey, who had studied the origin of the solar system and the chemical events associated with this process, began to consider the emergence of life in the context of his proposal of a highly reducing terrestrial atmosphere. Urey presented his ideas in a lecture at the University of Chicago in 1951, followed by the publication of a paper on Earth's primitive atmosphere in the Proceedings of the National Academy of Sciences(6).
Almost a year and a half after Urey's lecture, Miller, a graduate student in the Chemistry Department who had been in the audience, approached Urey about the possibility of doing a prebiotic synthesis experiment using a reducing gas mixture. After overcoming Urey's initial resistance, they designed three apparatuses meant to simulate the ocean-atmosphere system on primitive Earth (3). The first experiment used water vapor produced by heating to simulate evaporation from the oceans; as it mixed with methane, ammonia, and hydrogen, it mimicked a water vapor-saturated primitive atmosphere, which was then subjected to an electric discharge (see the figure below). The second experiment used a higher pressure, which generated a hot water mist similar to that of a water vapor-rich volcanic eruption into the atmosphere, whereas the third used a so-called silent discharge instead of a spark.
Miller began the experiments in the fall of 1952. By comparison with contemporary analytical tools, the paper chromatography method available at the time was crude. Still, after only 2 days of sparking the gaseous mixture, Miller detected glycine in the flask containing water. When he repeated the experiment, this time sparking the mixture for a week, the inside of the sparking flask soon became coated with an oily material and the water turned a yellow-brown color. Chromatographic analysis of the water flask yielded an intense glycine spot; several other amino acids were also detected. Experiments with the second apparatus produced a similar distribution and quantities of amino acids and other organic compounds, whereas the third apparatus with silent discharge showed lower overall yields and much fewer amino acids (primarily sarcosine and glycine).
After Miller showed the impressive results to Urey, they decided to submit them to Science. Urey declined Miller's offer to coauthor the report because otherwise Miller would receive little or no credit. Knowing that a graduate student could have a difficult time getting a paper like this published, Urey contacted the Science editorial office to explain the importance of the work and ask that the paper be published as soon as possible. Urey kept mentioning the results in his lectures, drawing considerable attention from the news media.
The manuscript was sent to Science in early February of 1953. Several weeks went by with no news. Growing impatient, Urey wrote to Howard Meyerhoff, chairman of AAAS's Editorial Board, on 27 February to complain about the lack of progress (7). Then, on 8 March 1953, the New York Times reported in a short article entitled, "Looking Back Two Billion Years" that W. M. MacNevin and his associates at Ohio State University had performed several experiments simulating the primitive Earth--including a discharge experiment with methane wherein "resinous solids too complex for analysis" were produced. The next day, Miller sent Urey a copy of the clipping with a note saying "I am not sure what should be done now, since their work is, in essence, my thesis. As of today, I have not received the proof from Science, and in the letter that was sent to you, Meyerhoff said that he had sent my note for review."
Infuriated by this news, Urey had Miller withdraw the paper and submit it to the Journal of the American Chemical Society. Ironically, at the same time (11 March), Meyerhoff, evidently frustrated by Urey's actions, wrote to Miller that he wanted to publish the manuscript as a lead article and that he wanted Miller--not Urey--to make the final decision about the manuscript. Miller immediately accepted Meyerhoff's offer, the paper was withdrawn from the Journal of the American Chemical Society and returned to Science, and was published on 15 May 1953.
On 15 December 1952, well before the Miller paper was sent to Science, K. Wilde and co-workers had submitted a paper on the attempted electric arc synthesis of organic compounds using CO2 and water to the same journal. They reported that no interesting reduction products, such as formaldehyde, were synthesized above the part-per-million level. This result supported the surmise of Miller and Urey that reducing conditions were needed for effective organic syntheses to take place. Surprisingly, when the paper by Wilde et al. was published in Science on 10 July 1953, it did not mention Miller's paper, although the authors did note that their results had "implications with respect to the origin of living matter on earth."
Miller's paper was published only a few weeks after Watson and Crick reported their DNA double-helix model in Nature. The link between the two nascent fields began to develop a few years later, when Juan Oró demonstrated the remarkable ease by which adenine, one of the nucleobases in DNA and RNA, could be produced through the oligomerization of hydrogen cyanide (8). It would eventually culminate in the independent suggestions of an "RNA world" by Carl Woese, Leslie Orgel, and Francis Crick in the late 1960s and by Walter Gilbert in 1986.
The impact of the Miller paper was not limited to academic circles. The results captured the imagination of the public, who were intrigued by the use of electric discharges to form the prebiotic soup. Fascination with the effects of electricity and spark discharges on biological systems started with the work of L. Galvani in 1780 with frog legs and the discovery of "animal electricity." And an everlasting impression was left in the public's imagination by Mary W. Shelley's Frankenstein (1818), in which Eramus Darwin gained a place for his advocacy of therapies based on electric discharges.
Although in 1953, few envisioned the possibility of Frankenstein monsters crawling out of Miller's laboratory vessels, the public's imagination was captivated by the outcome of the experiment. By the time that the results were corroborated by an independent group 3 years later (9), the metaphor of the "prebiotic soup" had found its way into comic strips, cartoons, movies, and novels, and continues to do so. In Harry Mulisch's novel The Procedure (1998), one of the central characters encounters disaster while paving his way to the glittering halls of Stockholm for achieving the artificial synthesis of life from a primitive soup.
But is the "prebiotic soup" theory a reasonable explanation for the emergence of life? Contemporary geoscientists tend to doubt that the primitive atmosphere had the highly reducing composition used by Miller in 1953. Many have suggested that the organic compounds needed for the origin of life may have originated from extraterrestrial sources such as meteorites. However, there is evidence that amino acids and other biochemical monomers found in meteorites were synthesized in parent bodies by reactions similar to those in the Miller experiment. Localized reducing environments may have existed on primitive Earth, especially near volcanic plumes, where electric discharges (10) may have driven prebiotic synthesis.
In the early 1950s, several groups were attempting organic synthesis under primitive conditions. But it was the Miller experiment, placed in the Darwinian perspective provided by Oparin's ideas and deeply rooted in the 19th-century tradition of synthetic organic chemistry, that almost overnight transformed the study of the origin of life into a respectable field of inquiry.
[Illustrations and footnotes in the original.]
But what the article said is that "An F indicates the texbook relies on logical fallacy, dogmatically treats a theory as an unquestionable fact, or blatantly misrepresents published scientific evidence".
On those three things 7 of the 10 textbooks were ranked F as opposed to D. And I am willing to bet that of the 7 F's most or all treat theory as an unquestionable fact.
You may not like the stand the Discover Institute takes on ID, but you can't fault them for criticising textbooks for including pictures of faked embryos, fabricated evidence and discredited experiments.
Why would any honest scientist not agree with their position against these things?
Because I'm in an obnoxious mood.
ALL scientists endure what might reasonably be interpreted as technical redicule during peer review--that is the function of peer review, and it is appropriate. Science is not a popularity contest, it is a contest of ideas, with the prejudice, all else being equal, properly on the side of the established doctrines. Science is not some hollywood beauty show where we crown queen the most photogenic idea of the moment.
So you agree that scientists have to go through a rigorous defense of their ideas to establish them, and you cite some examples? Where in all this is your disagreement with my assessment of the situation?
They do have to go through a rigorous defense. But they are not always attacked based on scientific principles. Infrequently they are attacked based on assumptions and theories that have not been proven true. And when such is the case, they are unwilling to even consider the science.
My point is that with such a list having been called crazy and charlatrans by the "scientific community", could it be that the scientific community is doing the same thing with ID?
Instead of critically examining the claims as an alternative theory, they dogmatically conclude that this is religion and exclude it from scientific publication and circles. And in so doing, they refuse to even consider the claims or look objectively at the evidence.
O'k'a'y. J'u's't w'o'n'd'e'r'i'n'g.
What? Well, of course it's dogmatic and exclusionary. That's the point. If you want to establish a competing new thesis, you have to face down the old thesis, and the peer reviewers that are, ideally, the old thesis's representatives. You don't hire a thief to guard your building, just as you don't hire sympathetic scientists to peer review a technical article in a journal that is fundamentally devoted to critical review of new ideas and their supporting evidence. It would be, frankly, kind of braindead if the peer-review process were not dogmatic and exclusionary.
It works better if the apostrophe can change the pronunciation into something obnoxious. Perhaps I should have added an extra e so that it was clear I meant "pee'er" review.
Certainly you want people who can be critical of a new idea. But, it seems to me that you shouldn't have to face down the old theory, but rather show that the new theory is plausible as well. If two theories are plausible, science should consider them both, until one of them is disproven.
Instead of a scientific scholarly critique, in sometimes turns out to be ridicule that is neither scholarly or scientific, but tantamount to making fun of a fellow scientist and his work on the same scientific level as laughing at his pee'er.
Certainly one must have sizeable gonads to endure the ridicule heaped on anyone willing to present a competing theory to even the smallest part of evolution. But as the previous list shows, this behavior on behalf of the "consensus" is not limited to controversial areas like evolution but rather mundane science as well.
It often looks like a huge (hugh) exercise in groupthink or petty jealous responses of the "not invented here" type.
Mantra - ideology freeks !
vg ...
Perhaps you get confused. Most people past the age of twelve are pretty capable of handling a diversity of opinions and information without confusion. Not so with True Believers who use mental compartmentalization in order to avoid mixing disparate facts that might lead them to doubt their faith. The mental effort (largely subconscious) required to maintain the compartments ... often leads to --- an impaired intelligence. Mixing, after all, is what intelligence is all about.
66 posted on 11/03/2003 8:04 AM PST by Vercingetorix
In pre-publication peer reviews for well-established technical journals--which is where the rubber presently meets the road--yes, they pretty much are.
Infrequently they are attacked based on assumptions and theories that have not been proven true.
There is no case of a "proven true" theory in natural science. All theories in science are assumptions that have not been proven true, and potentially overturnable by some ambitious scientist undergoing peer review.
And when such is the case, they are unwilling to even consider the science.
Say what? You are not describing the peer review process for extant, well-accepted scientific journals.
My point is that with such a list having been called crazy and charlatrans by the "scientific community", could it be that the scientific community is doing the same thing with ID?
All radical new ideas meet resistance--so what? That's why we convene peer-reviews and give them their day in court--if they're willing to do their homework.
Instead of critically examining the claims as an alternative theory, they dogmatically conclude that this is religion and exclude it from scientific publication and circles. And in so doing, they refuse to even consider the claims or look objectively at the evidence.
Hogwash. These claims get looked at all the time. ID is far from off the table--I'm an ID'er myself. The accurate and pursuasive claims that it ain't science are methodological, not fundamental. ID ain't science because it ain't ponied up before the court, not because it's necessarily wrong. A strong contingent of pretty bright scientists, including some Nobel winners such as Fred Hoyle, think it's necessarily right. But hardly any scientists get confused by this distinction, just a large passel of vocal creationists and creationist look-alikes, and the scientifically naive school board members they try to flim-flam with this 3-card monti they've been taught by the Discovery Institute.
Oh, by the way, there's a large measure of yawn factor in the apparent disdane for ID. The thing is, it probably is so, but it probably doesn't help much, or change much. It moves all the same problems onto a larger stage (the universe, instead of this planet) and it still doesn't shed much light on the basic questions we'd like answered, in some manner full of tasty technical details than lend to credibility through testability.
Creationists imagine that ID might represent some sort of victory for their contentions--they will be sadly disappointed.
Sounds sweet, and I'm sure it appeals to most kindergarten teacher's sense of fairness. However, what we are doing in science these days is betting the working lives of hundreds of scientists, and a fair measure of the community's available resources on the fruitful outcomes of future scientific experiments that are now very expensive to do. Furthermore, we have a sort of vested interest, and assumed duty to our children, to set a course through scientific discovery that doesn't end up being a dead end that wastes generations of scientific effort. So we try to bet our best hands--not every hand we could possibly be dealt.
Ptolomaic astronomy still accurately predicts the behavior of the planets, it has not been demonstrated to be wrong, just comparatively mathematically unwieldy--should we be fair and give equal time to ptolomaic astronomy in our high school textbooks?
So it's about funding. That's exactly one of the criticisms of evolution. The scientific community is not impartial. Not only are large amounts of existing funding at stake as well as jobs, but the community rewards someone finanicially who can discover the oldest "X".
Between funding considerations and an enthusiastic rejection of religious values, the scientific community is too slanted in support of evolution.
I think you should take a look at the latest (November 2003) issue of Scientific American. The rewards for successfully bucking the tide far outweigh the rewards of being timid. Of course you also have to be right.
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