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#of Amino Acids (Fourth Time!)

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(The first time precedes content item 1)

The article has a Reference #2 to a follow-up paper by Urey-Miller in 1959. The paper is available from the link given, but for discussion purposes, I have temporarily placed a copy here... delete the commas:

http,://,grandscheme,.org/,Urey-,Miller-,1959.pdf (seven pages)

On its page 248, in the left column entitled 'Electric Discharges', they explicitly refer to the 1953 paper (Reference #1 here), and go on to say: "A more complete analysis of the products gave the results shown in Table 2."

Table 2 is the top middle column on page 249. Also, a list of the 20 (why does the article say 22?) amino acids needed for life are shown here:

http://www.bio.davidson.edu/Courses/Molbio/aatable.html http://members.tripod.com/Diabetics_World/Amino_Acid_Details.htm

Four amino acids are immediately identifiable against the above list(s).

Is there anyone here technical to match up some of the other Table 2 items to amino acids?

I'm pretty sure the number of amino acids in the 1953 experiment that were identified by the 1959 "more complete analysis" by the original authors is 11. Here are two references for that:

http://www.accessexcellence.org/WN/NM/miller.php (Miller: "Just turning on the spark in a basic pre-biotic experiment will yield 11 out of 20 amino acids.") [and I should think Miller would know]

http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=461 ("Stanley Miller with his Nobel Laureate supervisor, Harold Urey, demonstrated that 13 of the 21 amino acids necessary for life could be made in a glass flask.") [11 is the conservative version of 13]

What do y'all think? My edit to make it '11 amino acids' was backed out by someone many months ago.

I think it's time to put it back in, with appropriate tweaks to the language of that paragraph. Anyone care to make the edit, now that we can see the "more complete analysis?" —Preceding unsigned comment added by Double Think (talkcontribs) 06:04, 8 September 2008 (UTC)[reply]

The edit has been made. Double Think (talk) 04:37, 23 September 2008 (UTC)[reply]

The article incorrectly states that all 20 'common' biological amino acids were isolated. Neither the original experiment nor Bada's followup show this. I'll make a quick correction and explicitly state this. WIll followup later and try to make the entire article clearer on this. Maneesh (talk) 17:10, 11 September 2012 (UTC)[reply]

#of Amino Acids *Other Experiments*

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Several vials from one of Miller's early experiments has apparently been reanalized with modern equipment and found to have twenty two amino acids and five amines.

Johnson AP, Cleaves HJ, Dworkin JP, Glavin DP, Lazcano A, Bada JL (2008) The Miller Volcanic Spark Discharge Experiment. Science 322(5900):404.

http://www.sciencenews.org/view/generic/id/37729/title/Primordial_soup_lives_again http://scienceblogs.com/pharyngula/2008/10/old_scientists_never_clean_out.php http://www.eurekalert.org/pub_releases/2008-10/iu-me101308.php —Preceding unsigned comment added by 64.183.111.242 (talk) 21:57, 17 October 2008 (UTC)[reply]

why were some vials unanalysed ?

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This is due to the recent discovery of some additional amino acids in the original experiments. The obvious question to me is: "why were these vials not analyzed after the original experiment?". If anyone finds the answer to that question, please add it here or to the article? Thank you --TheDJ (talkcontribs) 22:08, 20 October 2008 (UTC)[reply]

The lead specifies "re-analysis", it was done again with more sensitive instruments; which the article now does elaborate on. - RoyBoy 03:33, 21 October 2008 (UTC)[reply]
My error. They had been analysed before. Narayanese (talk) 17:17, 21 October 2008 (UTC)[reply]

Inorganic to Organic?

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This is quite a leap of scientific faith. Is this article trying to claim that the Miller-Urey experiment achieved fusion or fission of other elements into carbon and hydrogen? This experiment began with these elements in great abundance (in methane and carbon dioxide) and I don't recall that the stoichiometry ever indicated a sudden increase of either one. At any rate, I've never heard anyone describe an inorganic compound such as water reacting with an organic compound such as methane as "inorganic synthesized into organic" or words to that effect. Since organic compounds were present from the start, I think this wording is misleading.Hellasick (talk) 04:58, 22 October 2008 (UTC)[reply]

No, it is merely saying that this experiment proves that basic compounds like water and methane, under certain conditions, form molecules well known to be biological in nature, such as amino acids. --Pstanton (talk) 09:40, 1 February 2009 (UTC)[reply]

Creation-evolution controversy

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I feel that a link to Creation-evolution controversy is approp in the See also section. -- Alan Liefting (talk) - 20:42, 22 October 2008 (UTC)[reply]

I disagree. It's pseudoscience/religion, and so does not belong in a scientific article. And it doesn't even have anything in particular to do with the topic. Narayanese (talk) 20:49, 22 October 2008 (UTC)[reply]
Obviously, whether or not life can form from a random combination of particles is deeply involved with the creation/evolution debate. Or, as I call it, the intelligent design vs. one in a million chance debate. β i ι ι γ τ r ο υ § ε r § (talk) 21:06, 22 October 2008 (UTC)[reply]
I agree that it is pseudoscience/religion but that does not mean the link should not be included. The creationist controversy has important links (!!) to this article. The Miller–Urey experiment is one of the important discoveries that refutes the idea of creationism. -- Alan Liefting (talk) - 21:31, 22 October 2008 (UTC)[reply]
I disagree, it's not even pseudo-science. It has no connection whatsoever with anything near science. Otherwise agreed! Begone creationism! Said: Rursus () 13:31, 23 October 2008 (UTC)[reply]
And: it is a religion. Different from christianity. Said: Rursus () 13:36, 23 October 2008 (UTC)[reply]
A lot of the heat in the "Intelligent Design" versus "random genesis of biomolecules" argument would have been dissipated if more light had been allowed in the first place instead of having people telling other people to STFU (as we see upthread).
Let the arguments stand on their own merits. I have to admit to being a long-time disbeliever in abiogenesis until I read this article. Now I'm not so sure.
I think other people who are using Wikipedia to try and educate themselves on the basic issues surrounding the Intelligent Design vs. Random Biogenesis debate would benefit from being directed to this article. Certainly, I hadn't heard before I read this article that vials from the Miller-Urey experiment had been reanalyzed and more amino acids found.
Of course, the hallmark of any successful scientific experiment is reproducibility, the rock on which cold fusion and Podkletnov's inertial modulation experiment seem to have foundered. This article demonstrates that Miller/Urey was not just reproducible, but that it led to other successful experiments such as Juan Oro's synthesis of adenine from hydrogen cyanide and ammonia in water in 1961. So very far from being a failure, as it has been portrayed recently (http://www.chem.duke.edu/~jds/cruise_chem/Exobiology/miller.html)[1] , since it was a seminal work that did prove amino acids could be formed under conditions which, while extreme, could conceivably have existed in the primordial Earth.
The article succeeds in answering questions I had about how entropy (in the form of nitrites in the initial results, which would have tended to decompose any randomly created biomolecules as soon as they were made) was answered as an objection to random biogenesis. Wikipedia did its job by producing this article. The job would be done better if this article's place in the debate between Intelligent Design versus random biogenesis were mentioned.loupgarous (talk) 02:44, 2 September 2011 (UTC)[reply]
On the contrary - the Miller experiment is often held up as some kind of proof of abiogenesis. It is a fact that one can take certain chemicals and subject them to these conditions, and produce amino acids. It is evolutionists that attempt to go beyond what has been proven to argue that this is what actually happened, ultimately producing life. 2604:CB00:3201:1B00:89AC:FA74:B486:2A12 (talk) 22:27, 25 May 2022 (UTC)[reply]
We quote science in articles about pseudoscientific bullshit, but not the other way around. See WP:ONEWAY. Therefore creationism has no place here. Also, you are responding to a 16-year old contribution. --Hob Gadling (talk) 18:37, 26 May 2022 (UTC)[reply]

Yes, I agree with Alan Liefting. There are still a lot of people who believe in intelligent design - most Muslims, Jews and Christians, for instance. I've personally met several people who believe in intelligent design. —Preceding unsigned comment added by 125.240.61.2 (talk) 05:11, 23 October 2008 (UTC)[reply]

Please, sign your posts by writing four tildes like this ~~~~. Said: Rursus () 13:43, 23 October 2008 (UTC)[reply]
Please, don't sign your posts by writing nothing like this. It is what is written which is important not who writes it. Signing posts in Wikipedia is a guideline not a requirement. —Preceding unsigned comment added by 86.134.63.167 (talk) 22:06, 24 October 2008 (UTC)[reply]

This experiment is not in any contradiction with religions. Miller-Urey experiment produces mixture of complex organic compounds, which are not organized. It is not a Life, it is more like a dead body.Krasss (talk) 21:44, 23 October 2008 (UTC)[reply]

  • Has this specific experiment ever been cited in the debate? If not, I see no reason to include the link. If it has (in peer-reviewed publications), a case could be made for inclusion. - Mgm|(talk) 22:11, 23 October 2008 (UTC)[reply]
Why the requirement for the Miller-Urey experiment to have been included in the debate in peer-reviewed publications? As someone with a few peer-reviewed publications in his CV, I can tell you that debates such as this are generally discussed in the editorial pages of scientific journals and are not peer-reviewed. It's very unlikely that the intelligent design versus random biogenesis debate would wind up in a peer-reviewed article (outside, perhaps, a glancing mention in the "Conclusions" section of the paper). But the Miller-Urey experiments are often mentioned in this debate because they are very close to crucial in making a case for random biogenesis. And I am very purposefully restricting my terms - I am personally uninterested in the "creation versus evolution" argument - my faith does not depend on it.loupgarous (talk) 08:00, 2 September 2011 (UTC)[reply]
By the way, in my view, this experiment could go fine with both creationism and evolution. In creationism, God just did the reaction from this experiment. - Mgm|(talk) 22:13, 23 October 2008 (UTC)[reply]
I agree. In fact, a plausible fall-back position for Intelligent Design proponents would be that God created subatomic particles. That places the ball all the way back to the Big Bang, and Stephen Hawking could weigh in about gravity being the necessary and sufficient cause for Creation (no divine intervention required). Professor Hawking, however, doesn't explain where the mass necessary for the gravity that made the Big Bang came from, which gives the Intelligent Design people a place to stand.loupgarous (talk) 03:08, 2 September 2011 (UTC)[reply]

My friend you really don't get creationism huh in creationism every thing was created by God in 6 days which the 7th was rest for God. I think that this experiment was actually a bigger proof that spontaneous creation is impossible contradictory to the evolution point of view (spontaneous creation itself was already disproved by Louis Pasteur), in my point of view it disprove the view of evolution instead of proving evolution 20:13, 10th November 2009

In that case, your point of view is distorted, biased and bizarre. ;) 87.56.88.195 (talk) 11:27, 10 October 2010 (UTC)[reply]
Here in Wikipedia we assume good faith and don't attack contributors personally, even when they are in vivid disagreement with our view of the facts. Even when they drag in their religious mythology, which is clearly inadmissible as a source document in Wikipedia science articles.loupgarous (talk) 13:03, 2 September 2011 (UTC)[reply]
I don't think we have to refer to creationism. Creationism has nothing to do with science, and this article provides a scientific objective analysis of the Miller-Urey experiment.
The article doesn't state that our current understanding of life's origin is the absolute truth.
Of course scientifically based critisism on the experiment should be included, but that doesn't mean we should propose an alternative hypothesis witch uses the supernatural to explain the origin of life because that is per defenition not scientific and testable.
That's like including Zeus in an article about the models that explain how thunder works because those models aren't absolutely true and can be criticized on certain aspects.
There is an important distinction between Intelligent Design arguments and simple Creationist arguments. Intelligent Design arguments point to the physical evidence and have to be rebutted on that basis. The Miller-Urey and Oro experiments are parts of the rebuttal of Intelligent Design, so much so that they should be considered seminal to all the other work that has been done since in simulating the primordial Earth environment. If the scientific community has a claim to intellectual superiority to Creationists and Intelligent Design proponents, it ought to rest on the evidence. That's why reference to the Intelligent Design versus abiogenesis controversy is important.loupgarous (talk) 13:03, 2 September 2011 (UTC)[reply]

This page should mention when talking about some people doubting it (ei: there were right-handed amino acids in the mix,) that it was under continually refined conditions too make it perfect, in other words a carefully planned experiment not like the random lightning strikes water bam! The building blocks of life appear as would be described in the "warm soup." 173.69.205.215 (talk) 04:12, 22 November 2012 (UTC)[reply]

  1. ^ ""Miller-Urey Experiment"". Duke University Exobiology Web Site. Duke University Chemistry Department. Retrieved 2 September 2011.

Chemistry of experiment

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I would like a source stating that this is what happened. Also, a bit more explanation what [O] means could be useful, is it a way of saying a compound got an extra hydroxyl group? Narayanese (talk) 20:02, 25 October 2008 (UTC)[reply]

Hydroxyl group is [OH]. [O] is an atomic oxygen, it is not the same particle. Krasss (talk) 20:49, 25 October 2008 (UTC)[reply]
I have added some sources for this section. For other sources see the articles about methane, formaldehyde, hydrogen cyanide&BMA process, cyanoacetylene etc. Krasss (talk) 22:22, 25 October 2008 (UTC)[reply]
Those sources are for synthesis by chemists, not synthesis in a prebiotic environment. You are deriving your own hypothesis from sources on related areas; don't do that on Wikipedia (WP:SYNTH). Narayanese (talk) 22:48, 25 October 2008 (UTC)[reply]
Sorry, there was a few mistakes with adding of this links. Right links are [1] and [2].
Here is some citations from this sources:
"First, the gases in the "atmosphere" reacted to form a suite of simple organic compounds, including hydrogen cyanide (HCN) and aldehydes (compounds containing the group CHO ). The aldehydes then combined with ammonia and hydrogen cyanide to generate intermediary products called aminonitriles, which interacted with water in the "ocean" to produce amino acids and ammonia. Glycine was the most abundant amino acid, resulting from the combination of formaldehyde (CH2O), ammonia and hydrogen cyanide."
"An intriguing mechanism involves the synthesis of HCN via photochemical reactions between CH4 (of volcanic origin) and N2.45 If early in Earth’s history the mantle was much more reduced than it is currently, then the amount of CH4 emitted from volcanoes would have been greater. Rainout of substantial quantities of HCN would make the subsequent synthesis of purines, pyrimidines, and amino acids possible in the aqueous phase.46 Similarly, photolytic reactions initiated from CO2 and H2O at ultraviolet wavelengths have been postulated to produce rainout of formaldehyde (CH2O)47 with the possibility of subsequent condensation reactions yielding primitive sugars. This assumes that the concentration of formaldehyde rose high enough in aqueous solution on Earth’s surface."
=> So, you can see that it is not my own hypothesis. Krasss (talk) 23:31, 25 October 2008 (UTC)[reply]
Your reaction isn't very true to the text. Where did you read about carbon monoxide and atomic oxygen? The BMA process says it is done at 1400°C with platinum, rather than by light, so that link shouldn't be there. Narayanese (talk) 08:51, 26 October 2008 (UTC)[reply]
Narayanese, if you would be a chemist, these questions would be too trivial for you. Atomic oxygen formation is the first step of CO2 decomposition reactions. See, for example, this link [3]. This source is about microwave discharge, but the High-voltage process (in CO2) is almost the same. Other links about CO formation: [4], [5], [6], [7]. About BMA process you are right, but this reaction can also occure without any catalysts (for example, by UV-irradiation or discharge processes), - but the yield is less. Also, see the link about HCN synthesis from NH3 and CO [8]. Krasss (talk) 22:26, 26 October 2008 (UTC)[reply]
=> See also the link [9]. This link is on russian, but the pictures you can understand without translation. Krasss (talk) 22:52, 26 October 2008 (UTC)[reply]
Sorry for the late reply. The Russian article is clear enough. Narayanese (talk) 12:57, 1 November 2008 (UTC)[reply]


Miller-Urey Experiment Failed

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If you notice, there were four substances used in the experiment: water (H2O), methane (CH4), ammonia (NH3), and hydrogen (H2). These, apparently, were the four gasses that our “young” Earth’s gravitational pull could handle. An interesting thing about this is that Miller and Urey decided to leave out oxygen (O2). Oxygen is an essential gas to living organisms. They knew, however, that whatever was created in the experiment would oxidize. You know… leave a banana or an apple out on the counter too long it turns brown; it oxidizes. Essentially, it dies.

I have one minor change to this article. The reason that Miller and Urey decided to leave our oxygen was because it wasn't present in the atmosphere at the time that life appeared on earth. Oxygen only appeared once an excess had built up from photosynthetic plants which were using the abundance of carbon dioxide present at that time. Once oxygen was in surplus, new animals which used cellular respiration appeared and began to convert the oxygen back into carbon dioxide for energy. The order of life was excess of light/CO2/water, photosynthetic plants, chemosynthentic plants, surplus of oxygen, and the creation of animals.— Preceding unsigned comment added by WittleD (talkcontribs) 05:06, 25 May 2011 (UTC)[reply]

A serious problem arises at this point, though. With oxygen we have ozone. The ozone layer blocks out a lot of ultra violet light. Ultra violet light destroys ammonia. If you look back up at the previous paragraph, ammonia was one of the gasses used in the experiment. Hummm… this creates a problem, does it not? According to today’s “brilliant” scientists, there was no oxygen on our “young” Earth. This means no ozone. No ozone means UV rays. UV rays mean no ammonia!!! So, coming ‘round full circle, with oxygen: life can’t evolve! Without oxygen: LIFE STILL CAN’T EVOLVE!

One other thing I want to bring up is the Primordial Soup that Miller and Urey produced from their experiment. Today’s “brilliant” scientists say that the soup, or sludge in my mind, was “Rich in amino acids”. Wrong again… fortunately (yes I said fortunately). The sludge they produce was only 85 percent tar, 13 percent carbolic acid, 1.05 percent glycine (an amino acid), and 0.85 percent alanine (another amino acid). HARDLY EVEN 2% OF THE SLUDGE WAS AMINO ACIDS! On top of that is the fact that only two out of the TWENTY amino acids required to create a single, living cell were produced.

The interesting thing about tar and carbolic acid is that both are lethal to life. After a while, they would have killed the amino acids that were produced.

Scientists say that life first evolved in the oceans. This is wrong, too. The amino acids created would bond to the water molecules before they bonded with each other. With this in mind, even if the twenty acids required to create a single, living cell were available, the chances that they would bond with each other are still pretty slim.

"There is a more fundamental problem with this scenario which can easily be overlooked. Amino acids, like all chemicals, are three-dimensional structures. The arrangement of the central carbon atom is tetrahedral. Unless you are used to studying these sorts of arrangements, you will think they are the same; it would seem that you could just rotate one to get the other. This is not, in fact, the case. We compare them to our hands: right-handed and left-handed. A left-handed glove will not fit on a right hand, for example. Does this matter? The answer is a very loud “Yes!”. In nature, we only have left-handed (levo) amino acids. (Glycine mentioned above is an exception; it does not have two forms). Miller’s experiment gives a mixture of both forms but nature requires the levo form only. Again, does it matter? Functional proteins cannot contain more than traces of right handed (dextro) amino acids. Right-handed forms (dextro) can have very different, even fatal, effects in some circumstances. It is not a simple process to separate them and there is no natural system that can do so. In fact, L-amino acids have a tendency with age to undergo a chemical inversion to the D-form. This is called racemization. (This again gives a headache to the evolutionists: if amino acids could have been synthesised in a pure L-form, within a short time they would have racemized to give a 50:50 mixture of the two forms!). This racemization occurs in nature and can cause severe problems. For example, teeth and eye proteins racemize with age and so affect their health; Alzheimer’s disease also may be caused by racemization of a protein. This structural distinction is a property that occurs widely in organic chemistry. For example, from non-protein substances we can observe the effect. Limonene occurs in these two forms: one gives the smell of lemons and the other of oranges! More seriously, the drug thalidomide was produced to aid pregnant mothers in order to combat “morning sickness”. It was very effective but sadly serious deformities occurred in many babies. The reason was that the commercial drug was sold in a mixture of the handed forms." http://www.truthinscience.org.uk/site/content/view/51/65

The article does, actually, partly address the issue of strong acids - specifically, nitrites - being created by the spark gap by mentioning subsequent experiments in which reducing agents like carbonates which could have existed in the primordial "soup" were placed in the reaction chamber - drastically reducing the yield of nitrites. This doesn't, of course, deal with the phenol ("carbolic acid") in the soup - an issue the author neglects to deal with.
However, your assertion that "without oxygen, life can't evolve!" is just wrong. MANY electron donors (sulfur, for example) can take the place of oxygen in biological reactions - and do in the case of some thermophilic bacteria found in undersea volcanic vents. Oxygen is the BEST electron donor for this purpose and so in places open to the air NOW, organisms which use oxygen out-compete sulfur-loving organisms. But in a hypothetical primordial environment, if oxygen were unavailable, sulfur and other electron donors would have sufficed in oxygen's place.
Likewise, your discussion of optical isomerism ("handedness") in amino acids seems to assume the presence of organisms which depend on DNA and RNA as we know them - which would indeed have metabolic problems with using racemates of some amino acids. The article is referring to a postulated primordial state in which nucleic acids were still being synthesized - long before ribosomes which could have a "preference" for a given optical isomer of an amino acid existed.
One of the gaps in our knowledge of primordial abiogenesis is how nucleic acids polymerized in an environment so energetic that any polymers would seem to be degraded back to their constituent amino acids and sugars as soon as they were formed - which is where the presence of phenols in the spark gap "soup" is troubling if your scientific "faith" depends on abiogenesis being a fact. loupgarous (talk) 08:17, 2 September 2011 (UTC)[reply]

Once again, the experiment produces a problem for evolutionists. All the life we see around us always points to one thing and that is Intelligent Design. And no, I’m not talking about aliens. I’m talking about the Creator God; the God of the Bible.

This is my favourite website. Hopefully it'll prove to be of some usefulness. http://www.answersingenesis.com

Answers in Genesis is not considered a reliable source and what you have said is considered Original Reserch (which is also considerd unreliable). If you can find some real sources to support what you said then it will be added to the article. 121.217.44.27 (talk) 05:49, 5 March 2009 (UTC)[reply]
Agreed. The Bible is not an acceptable source for a science article. And in response to your original post in which you claim there isn't any oxygen, you seem to be missing the fact that there is oxygen in H2O... There is a number of problems in your argument, not the least your claim that carbolic acid would "Kill" amino acids. And finally, you claim the Miller-Urey experiment failed because it didn't produce all the Amino acids. Obviously they didn't, because the experiment lasted only one week. --Pstanton (talk) 06:36, 5 March 2009 (UTC)[reply]
I would agree that the Bible is not actually acceptable to most evolutionist as a source due to that they are "scientists". but here is a link which if more "scientific" than the answers in genesis so her it is: http://www.truthinscience.org.uk/site/content/view/51/65/ —Preceding unsigned comment added by Kudango (talkcontribs) 23:04, 1 September 2009 (UTC)[reply]
The Experiment is not failed, so as it is/was just a scientific experiment — with concrete and clear results. The problem is that it still cannot explain all mechanisms of origin of life. P.S. To authors and creationists: it would be better for you to create in the main article a new section, named "Criticizm", and then add there these weblinks. Krasss (talk) 23:49, 1 September 2009 (UTC)[reply]
Have you heard of the Encyclopedia of Evolution???? —Preceding unsigned comment added by 190.218.66.44 (talk) 02:44, 7 October 2009 (UTC)[reply]
this encyclopedia says that in the evolutionary point of view it is a failure. but i have to agree that this experiment is not a failure is some points since it proves that we can create amino acids but it is a failure since it couldn't create life. —Preceding unsigned comment added by 190.218.66.44 (talk) 23:46, 7 October 2009 (UTC)[reply]

Hmm... I'll give you that, 190.218.66.44. It did create a few acids, but didn't create life. Even if all amino acids were formed, though, there is still a problem. Have you heard of "Frog Soup"?[10] —Preceding unsigned comment added by 70.113.197.70 (talk) 20:27, 2 December 2009 (UTC)[reply]

Since, evolution is false I'm sure you have a citation to a single peer reviewed study that refutes the theory of evolution? ~RockBanned —Preceding unsigned comment added by 76.24.74.15 (talk) 16:04, 14 June 2010 (UTC)[reply]

I am not going to go off on you just because you mentioned Gensis, but you do make several valid points. Someone else mentioned that is was a success to show we can construct amino acids, but it was not consistent with the early earth. That seems to be true. The reasons you gave in your first paragraphs are concrete and scientific. Mmallico (talk) 22:28, 20 June 2011 (UTC)[reply]

Yhe hallmark of any successful scientific experiment is reproducibility, the rock on which cold fusion and Podkletnov's inertial modulation experiment seem to have foundered. This article demonstrates that Miller/Urey was not just reproducible, but that it led to other successful experiments such as Juan Oro's synthesis of adenine from hydrogen cyanide and ammonia in water in 1961.
So very far from being a failure, as it has been portrayed recently (http://www.chem.duke.edu/~jds/cruise_chem/Exobiology/miller.html)[1] , since it was a seminal work that did prove amino acids could be formed under conditions which, while extreme, could conceivably have existed in the primordial Earth.
The "failure" of the experiment as defined by other scientists goes to its possible variance from actual primordial conditions - specifically the requirement for large amounts of electrical energy over an extended period of time. However, this criticism is just as conjectural as the basis for the experimental design in Miller-Urey, so I don't think it rises to a complete rebuttal of the Miller-Urey results.!loupgarous (talk) 13:12, 2 September 2011 (UTC)[reply]
  1. ^ ""Miller-Urey Experiment"". Duke University Exobiology Web Site. Duke University Chemistry Department. Retrieved 2 September 2011.

Conclusion

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Um, exscuse me, but this article still doesn't seem to show that the experiment failed. Mcoolister (talk) 16:32, 14 March 2009 (UTC)[reply]

It didn't. Narayanese (talk) 16:58, 14 March 2009 (UTC)[reply]
Yes. It did. Mcoolister (talk) 17:30, 14 March 2009 (UTC) I'm going to look further into this. If I find any evidence that his experiment failed, I'll post it here.[reply]
Science clearly thought it went alright... Narayanese (talk) 18:11, 14 March 2009 (UTC)[reply]
I heard it didn't come out as he hoped. Like I said, I'll look into it. Mcoolister (talk) 19:22, 14 March 2009 (UTC)[reply]

An experiment cannot "fail" unless it yields erroneous results. This experiment, and it's results, have been replicated over and over again by many different people. Therefore this experiment was a success because it yielded a replicable result, which can then be used to confirm/falsify scientific hypotheses (ie, organic compounds can be synthesized with by primordial substances and electricity(confirmed) or that organic compounds can *only* be created magically by an immaterial intelligent force (falsified).72.253.205.13 (talk) 08:03, 6 June 2009 (UTC)[reply]

The article does not state that the assumptions in the hypothesis were wrong. Any honest scientist would simply state that a fact and move on. That is why this experiment is not being repeated by any reputable investigators. — Preceding unsigned comment added by 24.222.194.228 (talk) 03:31, 6 June 2011 (UTC)[reply]

There is a section called Earth's early atmosphere and it discusses the hypothesis. Variation of the experiment are being repeated. Ultimately, no one has a sample of Earth's early atmosphere but the fact remains his starting materials and even amino acids exist naturally therefore some chemical process created the amino acids. Vmelkon (talk) 13:02, 22 October 2012 (UTC)[reply]

Another idea for an experiment

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Maybe somebody could do an experiment like this; but instead of methane we use silane or germane etc. and see what comes out? --HawkFromHell (talk) 08:25, 17 March 2009 (UTC)[reply]

Silane and germane are not so stable as CH4, and the only result should be theirs decomposition; another reason is that these elements are not able to form stable Si-Si or Ge-Ge bonds. May be, experiments with phosphine (PH3) instead methane are more interesting, but I am not sure. Krasss (talk) 20:50, 27 August 2009 (UTC)[reply]
I'm not sure if silane is stable in the presence of water. If it is, it would be interesting to try. Apparently, germane has been detected on Jupiter. Vmelkon (talk) 12:56, 22 October 2012 (UTC)[reply]

Archive?

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The talk page is pretty long, and all threads look to be inactive, could someone who knows how archive this? --Pstanton (talk) 01:06, 5 April 2009 (UTC)[reply]

Done. Chris Cunningham (not at work) - talk 00:12, 21 August 2009 (UTC)[reply]

optical isomers and racemic?

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Hi, just a stupid creationist here with a question. The line that talks about optical isomers is confusing. I'm not trying to dispute anything, but there is absolutely no indication of why the facts related are relevant. As one who really dislikes bad arguments, throwing that out there without some sort of explination appears to be an attempt to pile up technical jargon to bolster an argument. I'm sure that's not the case, but some people might see it that way. Besides, an encyclopedia article should be clear about the relevance of all information included. I even linked over to the related pages, but there isn't any help there either as to why their appearance is relevant to this experiment. I'd really like to understand. Any help? —Preceding unsigned comment added by 71.168.3.195 (talk) 21:46, 24 May 2009 (UTC)[reply]


The L-isomers are the ones that tend to be found in biologically active proteins 88.107.85.238 (talk)DK —Preceding undated comment added 18:14, 27 August 2009 (UTC).[reply]

Which you would have found out if you'd clicked on the words you were confused by. optical isomers. Hypertext is awesome. -- Ec5618 (talk) 12:52, 1 December 2009 (UTC)[reply]

'Conditions do not match that of early Earth...'

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A very bold statement: 'However, advances in science since the original experiment have shown that the conditions of the experiment do not match that of early Earth as originally proposed.[9]'

From the source:

'There has been a recent wave of skepticism concerning Miller's experiment because it is now believed that the early earth's atmosphere did not contain predominantly reductant molecules. Another objection is that this experiment required a tremendous amount of energy. While it is believed lightning storms were extremely common on the primitive Earth, they were not continuous as the Miller/Urey experiment portrayed. Thus it has been argued that while amino acids and other organic compounds may have been formed, they would not have been formed in the amounts which this experiment produced.'

This merely says that 'it is now believed that early Earth's atmosphere did not contain predominantly reductant molecules' and 'lighting storms [on early Earth] (..) were not continuous as the Miller/Urey experiment portrayed'.

I think 'advances in science (..) have shown' should be changed into '[after some] advances in science (...) it is now believed'.

--Shought (talk) 21:12, 20 July 2010 (UTC)[reply]

I agree. At the end of the day, speculation about primordial Earth conditions is still conjectural. And even transient electrical discharges could have created enough amino acids for local biogenesis to occur, conceivably, given even local concentrations of the postulated materials (say, near a volcanic vent). I think that the Miller Urey experiment stands on the basis it established ONE set of circumstances in which amino acids could be formed by the environment. It has been the basis for much subsequent work in exobiology.loupgarous (talk) 13:30, 2 September 2011 (UTC)[reply]

Removed from lead

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I've cut a bit of quibbling from the lead that didn't appear in the article body and was about more recent interpretations of earth's early atmosphere (along with some ID stuff). The article is about the Miller-Urey experiment and its place in the history of science. Yes, including more recent scientific works and their relation to the experiment is a valid extension to the article. But long ref quotes in the lead section don't belong. And the ID "critique" is totally out of place. Vsmith (talk) 01:06, 12 January 2011 (UTC)[reply]

Dear User:Vsmith, in this edit you removed a large amount of referenced information from the introduction of the article. I have moved the content from that paragraph to a new section in the article. I hope this helps. Thanks, AnupamTalk 01:57, 12 January 2011 (UTC)[reply]
'Twas better in the body ... however, the intelligent design stuff is rather irrelevant coatracking and I've removed it again. Also the "When the Stanley Miller tested ..." bit as absurdly worded and please - we don't quote great globs from google books in a reference as for one thing it makes editing very difficult. Vsmith (talk) 02:47, 12 January 2011 (UTC)[reply]
Also, stating "However, in current times..." and then supporting that with an obsure 1977 book seems rather odd. Also the other reference used is a 1977 college textbook, surely we can do better. The ref to Science paper by Johnson et al is already used in the section "Recent related studies" further down in the article. So, the section suffers from redundancy and outdated/obscure refs. Vsmith (talk) 03:04, 12 January 2011 (UTC)[reply]
Much of the other sections in the article are not referenced, including the "panspermia hypothesis" assertion. I will work on the article when I am able to later. Only one sentence discussed the views of ID, which should be mentioned, since that is a view held by a significant group of people. If you object to certain references, please add the "verify" tag instead rather than removing the material. I will discuss and find more references in the future. For now I have eliminated some of the problems you have addressed, such as using the word "current," by naming the specific scientists. I would appreciate your cooperation. Thanks, AnupamTalk 04:23, 12 January 2011 (UTC)[reply]

Chirality

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Why no discussion of chirality? The enantiomeric mixture of the resulting chemicals is a crucial point. —Preceding unsigned comment added by 75.83.82.224 (talk) 21:29, 18 January 2011 (UTC)[reply]

  • Because chirality is irrelevant; it's a creationist red herring. The experiment took place over one week, while the formation of the "primordial soup" would have taken millions of years, enough time to produce molecules of all imaginable chiralities. Bubbha (talk) 20:10, 11 August 2011 (UTC)[reply]
Chirality is irrelevant to the consideration of prebiotic conditions. It only becomes important when an existing organism has to metabolize an amino acid whose chirality is incompatible with its cells' ribosomal structure and thus metabolically unusable or even toxic. That is not a consideration in the environment Miller and Urey postulated.loupgarous (talk) 13:21, 2 September 2011 (UTC)[reply]

Afaik there is experimental evidence that archae bacteria didn't use specific enantiomers as much. It seems to be a later refinement. Also, strictly, production wouldn't matter if life could selectively absorbe a particular enantiomer. So even if it is crucial to life, the difference needn't be in production from abiotic material per se.

I believe it's got something to do with whether amino acids were delivered from space c.f. carbonaceous chondrites. Kortoso (talk) 23:29, 15 August 2014 (UTC)[reply]

New analysis of a 1958 experiment

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An interesting new analysis might warrant a mention:

Archived samples from a 1958 Stanley Miller electric discharge experiment were discovered and analyzed. Johnuniq (talk) 07:47, 23 March 2011 (UTC)[reply]

I will add these to "Related links". Kortoso (talk) 20:26, 11 September 2013 (UTC)[reply]
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One link from the External Links sections is dead: A Production of Amino Acids Under Possible Primitive Earth Conditions by Stanley L. Miller, Science, v.117, May 15, 1953 —Preceding unsigned comment added by 188.27.196.98 (talk) 17:05, 1 April 2011 (UTC)[reply]

Citation needed: Wm MacNevin

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I don't know how to reply to the Main page, so here goes. The "citation needed" comment asks: "is it not clear [if he ever published any of these results in the primary scientific literature] because academics have researched this and somehow can't tell, or is it just not clear to the Wikipedia contributor from reading only the NYT article?"

The NY Times article cited mentions MacNevin's OTHER early work with no details. The contributor (me), searched the literature indexes (Chemical Abstracts, etc.), contacted several people at the OSU chemistry department, OSU librarians and OSU archivists to try to track down any other publications (peer reviewed journal articles, theses, etc.) or unpublished archived materials (personal papers, letters, rejected manuscripts, etc.) by MacNevin or his students and they found none. I don't think they searched very hard, but they did some searches. I suppose you can change the Main article to: "There are no papers published by MacNevin describing this other work indexed in Chemical Abstracts." AdderUser (talk) 13:00, 15 May 2011 (UTC)[reply]

Miller, not Miller-Urey, experiment

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The original journal report seems to be a single author paper: Miller, S. L. "Production of Amino Acids under possible Primitive Earth Conditions", Science v117(3046), pp 529-529, 1953.

That makes it the Miller experiment, not the Miller-Urey experiment. Urey chose not to be a coauthor, and the scientific community should accept that choice. — Preceding unsigned comment added by 223.206.15.181 (talk) 03:25, 28 September 2011 (UTC)[reply]

Miller was his grad student, say no more. Kortoso (talk) 21:02, 11 September 2013 (UTC)[reply]

Citation number 20

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Citation number 20's URL is obsolete, however there is a new URL: http://www.micro.siu.edu/micr425/14.pdf I'm not sure if it is the same, though.

24.13.209.132 (talk) 01:05, 4 March 2012 (UTC)[reply]

Citation #22

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...is a dead link. — Preceding unsigned comment added by 74.92.174.105 (talk) 20:03, 29 June 2012 (UTC)[reply]

RGA1980 and Trail's Nature Paper

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Hi RGA1980,

I pulled down both Trail et al.'s "The oxidation state of Hadean magmas and implications for early Earth’s atmosphere" as well as the companion "Earth science: Redox state of early magmas" in Nature 480:7375 (Dec 1 2011). I don't see Miller-Urey mentioned anywhere. While this work may have some bearing on it I think you'll be better served by finding a cite that makes the connection explicitly. Thanks. Garamond Lethe (talk) 07:44, 25 April 2012 (UTC)[reply]

Clarity of "Earth's early atmosphere" section

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I found this section hard to understand. Consider the sentence:

"In fact, in order to generate aromatic amino acids under primitive earth conditions it is necessary to use less hydrogen-rich gaseous mixtures."

On my first reading I thought this meant: there has to be hydrogen in the gas for amino acids to successfully form (i.e. high hydrogen content makes the atmosphere more inhospitable to amino acids). The next paragraph suggested I misunderstood, as it suggested high hydrogen content makes the atmosphere more hospitable - so I guess the hydrogen content clause isn't about "in order to generate", but rather about "under primitive earth conditions", that they believed the early atmosphere was lower in hydrogen (and thus less hospitable). — Preceding unsigned comment added by Hugovdm (talkcontribs) 09:31, 12 November 2012 (UTC)[reply]

Criticism in the press

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See [11] for some criticism that suggests revisions may be warranted to the text stating: "Experiments using these gases in addition to the ones in the original Miller-Urey experiment have produced more diverse molecule.". This is prominent in the intro so worth at least considering. Dcoetzee 23:20, 13 November 2012 (UTC)[reply]

It's "Evolution News". They're wrong, but it might be interesting figuring out if they've found a new way to be wrong..... I'll take a look. (BTW: EN isn't "press". It's an Intelligent Design blog.) GaramondLethe 23:27, 13 November 2012 (UTC)[reply]
Well, how about that: Casey Luskin did find a novel way to be wrong. The cite he quotes in the lede used to be (correctly) sourcing the discussion on chirality issues. It looks like to me that there was a copy-paste error when that cite was added to the lede, and it'll take a bit of work in the diffs to track down what the correct citation should have been. Casey (being Casey) doesn't know enough chemistry to see that this is an obvious typographical error and proceedes to get terribly excited and blog about it. Thanks for the help, Casey!
I'm on travel this week so I might not get to this for a while. Others are welcome to have a look. (I'm really curious to see if I was the person who introduced the error....)
I'm going to remove the current incorrect cite. If this stays uncorrected for a while I'll go back and add a "citation needed" tag. GaramondLethe 23:52, 13 November 2012 (UTC)[reply]
Looks like the editor copied the reference that was one below the one intended. Fixed. GaramondLethe 15:04, 14 November 2012 (UTC)[reply]
Still a bit iffy citing an old SciAm article about a work in progress: the paper was published in 2008 so I've added a citation to it. Quite interesting. . dave souza, talk 20:23, 19 November 2012 (UTC)[reply]
Good point — thanks for cleaning that up. GaramondLethe 23:16, 19 November 2012 (UTC)[reply]

alpha amino acids only?

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I find it very suspicious that all (AFAIK) articles in the references only speak of 'amino acids'. As many of you might know, the building blocks of proteins are alpha amino acids. So, it could be that the cited 'many', 'well over 20 different', 'easily bring out 30 or 40 more amino acids in very low concentrations' could very well be other molecules containing amino and carboxylic groups (and thus by the definition of the term, be amino acids) that have no biological significance. This should be noted in the article. Northfox (talk) 13:48, 13 January 2013 (UTC)[reply]

Seems reasonable, but would need a reference making those points.
Also removed the citation needed tag on the BBC episode ref. Seems there exist copies out there based on google search - haven't tried to download (slow connection precludes that:). Perhaps a verify tag would be better (?). Also found a BBC book (ISBN 978-1616168773) through an Amazon search, perhaps t'would be available through a library. Vsmith (talk) 14:47, 19 January 2013 (UTC)[reply]
Life is more than protein. Kortoso (talk) 23:32, 15 August 2014 (UTC)[reply]
Completely agree with you BurstPower (talk) 17:49, 8 November 2015 (UTC)[reply]

Criticism?

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This article, arguably more so than any other biology article, needs a criticism section. This experiment has been debunked several times(By REAL scientists, not creationists). — Preceding unsigned comment added by 99.199.53.35 (talk) 00:15, 4 April 2013 (UTC)[reply]

What do you mean by debunked? When someone says debunked, it makes me think the experiment doesn't actually work. Also, you should provide reference articles. Vmelkon (talk) 22:17, 19 April 2013 (UTC)[reply]
Well i am also in complete support of Criticism section. A lot of misinformation in this article BurstPower (talk) 17:48, 8 November 2015 (UTC)[reply]

Organic / Inorganic

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The intro contains the following ...

Specifically, the experiment tested Alexander Oparin's and J. B. S. Haldane's hypothesis that conditions on the primitive Earth favored chemical reactions that synthesized organic compounds from inorganic precursors

This is clearly wrong since organics cannot come from inorganics (assuming that by 'organic' we mean carbon containing molecules). I propose changing this sentence to ...

Specifically, the experiment tested Alexander Oparin's and J. B. S. Haldane's hypothesis that conditions on the primitive Earth favored chemical reactions that synthesized more complex organic compounds from simpler organic precursors Leor klier (talk) 23:20, 26 November 2013 (UTC)[reply]

Creatards keep adding this nonsequitor:

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“As of the date of the publishing of the previous statements, no spontaneous generation has demonstrated the smallest lifeform can be produced in this manner. The smallest genome is 112,000 base pairs. The same forces making these amino acids would destroy any genome. The association of this with abiogenesis has yet to be proven.”

The purpose of the Miller/Urey-Experiment is for discovering whether, under plausible conditions, one can created molecules life used under plausible prebiotic conditions. I Personally doubt that any sane scientist expects that something will crawl out of the reactionvessel. The creatards keep adding the above paragraph.

The long process leading from generation of molecules life uses to life is chemical evolution. Miller/Urey-Experiment and chemical evolution together, with a few other fields go under the banner of abiogenesis. The creatards need to stop vandalizing this article. — Preceding unsigned comment added by 76.103.108.158 (talk) 03:23, 16 April 2014 (UTC)[reply]

Maybe this article needs a "Criticism" section where documented concerns may be aired. :-Kortoso (talk) 21:38, 13 October 2014 (UTC)[reply]

Avoid criticism sections. Instead discuss how the experiment has been viewed with later research. --Harizotoh9 (talk) 15:42, 14 October 2014 (UTC)[reply]

Factual errors

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The article should be edited by someone who has less than vague knowledge in chemistry, and who actually has read Miller's scientific papers. It is riddled with a ton of misinformation, such as:

  1. Miller started in 1952 (not 53) and published it in 1953 (not "the following year")
  2. Prebiotic soup theory, of Haldane and Oparin, posits that organic compounds are synthesised form inorganic ones (not "simpler organic precursors")
  3. There were only two glass flasks, namely 500 ml and 5 l (not "glass flasks and flasks")
  4. The mixture turned pink in colour after one day (not "within a day")
  5. The reaction took one week (not "two weeks")
  6. It was qualitatitve experiment using paper chromatography, hence impossible to know the amounts of chemicals (not "10–15% of the carbon" or "glycine as the most abundant"
  7. Only amino acids were detected (not "sugars")
  8. Miller's statement "11 out of 20 amino acids" is not about his original work alone, but his lifelong synthesis up to 1996, and not appropriate for the section
  9. Most importantly, the title should be named "Miller experiment" as used in technical papers, opposed to "Urey-Miller experiment" popularised by textbooks and media. The reasons are:
    1. Urey's name was not included in the publication (nor in the subsequent papers of Miller). The fact is Urey wanted the credit to Miller alone, and he vehemently fought for its publication in Science. It's really quite a surprise.
    2. Scientists in the field use "Miller experiment" much more frequently, see (Google Scholar and [title Pubmed]) than other names. Chhandama (talk) 05:38, 5 November 2014 (UTC)[reply]
And the figure showed CO as one of the gasses in the original experiment for nearly 7 years until I fixed it. Re (6), (7), and (8), it looks like the Experiment section needs to be changed to clarify what was originally published and what was what was discovered in subsequent analyses. Maybe split into Original publication and Later analyses or similar? Adrian J. Hunter(talkcontribs) 06:09, 5 November 2014 (UTC)[reply]
  • Yes indeed. In addition:
  1. "...[T]he water could condense and trickle back into the first flask in a continuous cycle" is simply wrong. The resultant water containing the reaction products was stopped in a trap, see the diagram, from where samples were collected.
  2. The "Chemistry of experiment" is actually for his second experiment published in 1955 and is quite irrelevant. It is probably violation of Wikipedia:Original research policy. (I suspect somebody's fiddling with his/her chemistry notebook.)
  3. "As observed in all subsequent experiments, ... most of the compounds are non-racemic, or homochiral" smells fishy, and reeks of creationist/ID propaganda. There is no problem in chiral bias; in fact we should expect all possible mixture, but the primitive genetic system (RNA) is selective for L-aa.
  4. "This has been used to infer an origin of life outside of Earth: the panspermia hypothesis" is not very innovative, as an unsupported claim. Organic compounds in Murchison meteorite (and other carbonaceous chondrites) do not specifically support panspermia, they could well be an evidence for direct abiogenesis on earth.
  5. The last two paras under "Recent related studies" are the same story, just badly repeated. And it (not they) is not a "related study", but a direct reassessment of the original products using modern sophisticated chemical analysers. Chhandama (talk) 04:03, 6 November 2014 (UTC)[reply]

Extraterrestrial sources

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This is probably a piddling matter, but the gist of this experiment was to see if Earth's primordial conditions could create chemistry supportive of life. Does the section on comets and asteroids really help this topic? Kortoso (talk)

Amino acids identified

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I have added a table of amino acids identified in the original experiment and in the 2008 and 2010 repeats. I think it's useful to be able to see what amino acids were synthesised, and what weren't. The asterisk is not the most elegant indicator of the presence of an amino acid, but I don't know how to get anything better. If anybody can improve on it that would be great. I am taking a chance that "α-AAA" stands for α-aminoadipic acid, but otherwise I'm confident that my expansions are right. There seems to be an intermediate stage. The 2008 authors said that eight of their 22 amino acids were new, so there must be an earlier experiment or experiments where 14 amino acids were found. Miller said in his 1996 interview that you could get "11 out of 20 amino acids", presumably meaning 11 proteinogenic amino acids. Intriguingly, the 2010 experiment produced exactly 11 proteinogenic amino acids, 14 years later. Scolaire (talk) 15:05, 7 April 2016 (UTC)[reply]

Looks good. We have an entry for "S-methylcysteine". I know that's a real compound, but can you check that it isn't 5-methylcysteine instead? Thanks!
Kortoso (talk) 17:06, 7 April 2016 (UTC)[reply]
No. I don't think 5-methylcysteine even exists, since cysteine has only three carbons. It's probably a misprint for S-methylcysteine (where the methyl group is on the Sulfur, not on a carbon). Were you thinking of 5-methylcytosine, by any chance? Scolaire (talk) 17:57, 7 April 2016 (UTC)[reply]
Ah, good catch, you must have young eyes, lol. Kortoso (talk) 19:56, 7 April 2016 (UTC)[reply]
Belated thanks to Ringbang for reformatting the table. It looks much more professional now. Scolaire (talk) 09:18, 30 August 2017 (UTC)[reply]

Chemistry of experiment

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The section "chemistry of experiment" has two problems. First it is entirely unreferenced, so a reference should be added or the section removed. Second, it mentions the compound cyanoacetylene, leaving the impression that that compound was discovered in this experiment. That implication is challenged ticket:2016052710021807 So we either need a strong reference supporting the claim we need some major editing. Even if the chemistry is that compound wasn't discovered in the experiment.--S Philbrick(Talk) 15:01, 6 June 2016 (UTC)[reply]

About cyanoacetylene, see for example the next link. Citation from there: "Cyanoacetylene has been proposed as a prebiotic reagent for the formation of pyrimidine bases, nucleosides, and nucleotides (Sanchez and Orgel 1970; Powner et al. 2009)." Krasss (talk) 18:09, 13 January 2017 (UTC)[reply]

Why the vaccuum pump?

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Why is there a connection to a vaccuum pump? It is not mentioned in the text. The whole experiment took place at "ambient" pressure (well, ambient "du jour" for assumed prebiotic conditions). The electical discharge was high voltage, just like the lightning it simulated, so it didn't need low pressure. Very confused. — Preceding unsigned comment added by 101.175.140.117 (talk) 12:15, 24 September 2016 (UTC)[reply]

Interesting! The diagram from which it is supposedly derived has a gas inlet there, for the introduction of methane and ammonia. I can't see why it was changed to a vacuum pump. Scolaire (talk) 12:29, 26 September 2016 (UTC)[reply]
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CO2?

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Maybe I'm missing something, but under "Chemistry of Experiment" CO2 is listed, but the article says the experiment consisted of H2O, CH4, NH3 and H2. Where did the CO2 come from? It needs explaining.

80.47.44.54 (talk) 17:14, 15 July 2020 (UTC)[reply]

Some Credit to Mary Shelley?

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The video in this Article is remarkably similar to this video: https://www.youtube.com/watch?v=1qNeGSJaQ9Q . Should we give some credit to this famous science fiction author for her 1918 novel depicting the animation of matter with lightening? Charles Juvon (talk) 00:06, 20 October 2020 (UTC)[reply]

If there is a reliable source making this connection, then yes. Otherwise no. Orange Suede Sofa (talk) 03:22, 20 October 2020 (UTC)[reply]
After doing some searches, I think we can say: "Media and pundits have made a connection between Mary Shelly's Frankenstein and the Miller-Urey experiment, with cartoons depicting Frankenstein crawling out of a test tube." This says more about how people viewed the experiment in the 1950's than any precedent in the scientist's thinking. — Preceding unsigned comment added by Charles Juvon (talkcontribs) 19:48, 20 October 2020 (UTC)[reply]
No, we cannot, since, as you have already been told, we do not have a reliable source for that. Also, it's 1818, not 1918. --Hob Gadling (talk) 07:18, 4 November 2020 (UTC)[reply]

Carbon dioxide.

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It says, "One-step reactions among the mixture components can produce hydrogen cyanide (HCN), formaldehyde (CH2O), and other active intermediate compounds (acetylene, cyanoacetylene, etc.): CO2 → CO + [O] (atomic oxygen)" But where does the carbon dioxide come from? There has been no mention of carbon dioxide up to this point. The Experiment section states that the chemicals placed in the flask are water, hydrogen, methane, and ammonia. H2O, H2, CH4, and NH3, respectively. No mention of CO2 in that section. Polar Apposite (talk) 13:55, 22 November 2022 (UTC)[reply]

relevance to the origin of life - section's picture

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the picture describing the " enantiomeric excess" ratio has at its bottom a writing (in pic format). This ends in something like L-version/D-version >0. Probably a mistake, since the division of two numbers should not be 0 in any circumstances. I suppose the picture's author wanted to say that the ratio is not =1, that is the two antinomers will not be in an equal ratio. Perhaps, if theres an editor more versed in how can you correct a picture, this mistake could be amended.

If this is not a mistake, then probably some explanation is due in the description of the picture in order to avoid misunderstanding.

Sorry, just realized that my whole previous comment was unwarranted. the difficult to follow equation at the bottom of the picture just means that in the whole mixture the difference between the constituting two compounds will be more than zero, eg: the L and the D enantinomers will not be of exactly the same amount. Anyway, no need to "correct" the equation. Though it is not very easy to follow, but there is no mistake. 62.92.48.67 (talk) 11:03, 14 May 2024 (UTC).[reply]