Chemical evolution:

Discussion in 'Biology & Genetics' started by paddoboy, Aug 7, 2020.

  1. Q-reeus Banned Valued Senior Member

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    That he is a Messianic Jew is no secret he tries to hide. I myself have in an earlier thread described his belief in the bible as inerrant Holy Writ as a prime example of compartmentalized thinking. Have no idea what 'Disco 'Tute party line' means, and likely no one else here does either. But to assert there is 'no scientific argument in anything he says about the origins of life and he has done no relevant research in the field.' is imo extremely unfair. OK exchemist, you as a devout Catholic atheist (defining oxymoronic), how about getting down to specifics instead of a carte blanche condemnation. Tour makes specific claims in the vid I linked to. Which of those do you as an ex chemist object to? On what grounds precisely?
    Please link to the relevant article. Further to any follow up article where Tour acknowledges any misrepresentation/errors and sets such in proper context. Perhaps this one:
    https://www.jmtour.com/wp-content/uploads/John-West-on-Szostak-Article.pdf
    If that is relevant, do yourself a favor and read the entire article. His regretted use of 'lying' is there in context a very minor matter set against his overall critique.
    Fourth para p2 there reads:
    And this rather trivial misattribution by Tour somehow undermines his general thrust against unguided abiogenesis? Utter nonsense. Please go ahead, itemize the particular claims Tour makes in the vid I linked to in #13 that in his professional opinion undermine naturalistic abiogenesis. Then point out precisely where in your opinion he gets it badly wrong. Item by item. Chemist up against chemist. This should be interesting!

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  3. exchemist Valued Senior Member

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    I went through the article I linked and I have summarised the only relevant points Tour made.

    As for the video that I reviewed, I only mention it as evidence of Tour's bad faith when it comes to this subject.

    I can't be arsed to sit through 22 minutes of tendentious video presentation. I watched the first couple of minutes, which consisted of a repetitive series of false statements claiming that a synthetic organic chemist like him is automatically an authority on abiogenesis research, even though he has done none of it himself. It's designed to browbeat the viewer into thinking that whatever he says must be right - which is cock. (This video is in fact produced by none other than the Disco 'Tute*, I see - thus confirming nicely what I said about him trotting out the Disco 'Tute line.)

    If you can provide a transcript, or some other written material of his, I might read that and comment - if it's not too long and I'm bored enough.

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    But nobody takes Tour at all seriously on abiogenesis. He has published nothing in the area. His interests and expertise lie in quite another direction.


    * For those that don't know, Disco 'Tute is short for the Discovery Institute, in Seattle, the organisation that is responsible for promoting the pseudoscience of Intelligent Design. The name "Disco 'Tute" was given to it by PZ Myers in the blog Panda's Thumb, which is widely read by those interested in demolishing ID.
     
    Last edited: Nov 24, 2020
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  5. paddoboy Valued Senior Member

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    No just as I said, your previous nonsensical claims re many things, all without the required convincing evidence.
    I assessed what I saw...an opinion. You're lucky q-reeus, I didn't watch any of the many videos supposedly supporting Fat Freddy and his shenanigans.
    As are the qualifications of many other biologists and associated scientists who poo poo his inferences.
    Scientific as defined by the scientific method, and sensibility.
    Just a quick giggle

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    at that red highlighted bit.

    Tout gave an opinion...got it? An opinion with no evidence supporting your favourite, or his favourite scenario...nonsensical ID myth.
    Here's some more scientific research on the refining of time frames with regards to the formation of stars and planets and the following synthesisation.

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    http://www.sciforums.com/threads/solar-system-formation-in-200-000-years.163741/
    the paper:

    https://science.sciencemag.org/content/370/6518/837

    Astronomical context of Solar System formation from molybdenum isotopes in meteorite inclusions:

    Timing Solar System formation

    The oldest solids that formed in the Solar System are calcium-aluminium–rich inclusions (CAIs), small metallic droplets that were later incorporated into meteorites. The ages of CAIs are conventionally taken as the age of the Solar System, but which exact moment in star formation they correspond to has been unclear. Brennecka et al. measured molybdenum isotope ratios in CAIs and found a wide range of origins in both the inner and outer Solar System. They propose that CAIs formed from heterogeneous material accreting from the presolar nebula and that the ages of CAIs coincide with the Sun's transition from a protostar to a pre–main sequence star.

    Science, this issue p. 837

    Abstract

    Calcium-aluminum–rich inclusions (CAIs) in meteorites are the first solids to have formed in the Solar System, defining the epoch of its birth on an absolute time scale. This provides a link between astronomical observations of star formation and cosmochemical studies of Solar System formation. We show that the distinct molybdenum isotopic compositions of CAIs cover almost the entire compositional range of material that formed in the protoplanetary disk. We propose that CAIs formed while the Sun was in transition from the protostellar to pre–main sequence (T Tauri) phase of star formation, placing Solar System formation within an astronomical context. Our results imply that the bulk of the material that formed the Sun and Solar System accreted within the CAI-forming epoch, which lasted less than 200,000 years.
     
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  7. paddoboy Valued Senior Member

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    Just quickly, the small parts of the video I did watch, [near the start and the final few minutes] was notable in his manner of speech...upward inflections, downward inflections, increase in the volume of his so called message/crusade, at times to near a shout....you know, similar to what you may hear in a church with a priest preaching his fire and brimstone!

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    And of course the utmost [if unsupported] certainty as per the quoted bit.

    It seems someone else has picked up on that above point, more or less, I am trying to make.......
     
    Last edited: Nov 24, 2020
  8. paddoboy Valued Senior Member

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    Here is another interesting video.....Please, please, please!!! listen particularly from the 1 minute 30 second mark, to gauge the agenda that this James Tour is saddled with,,,,amazing!!!

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    such gaul!!!

     
  9. paddoboy Valued Senior Member

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    Here's another video of James Tour evangelizing about the Resurrection, and the "structure of the scriptures"
    Let me say that what James believes is his business, and whether he follows and puts faith in Jesus and the bible is also his business.
    What the last two videos show is that this man obviously, and despite his recognised expertise in chemistry, does have an agenda...in fact his words, reveal a fanatical agenda to put it mildly.

     
  10. paddoboy Valued Senior Member

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    Here is a critique of Tour's claims by Larry Moran: He is a Professor Emeritus in the Department of Biochemistry at the University of Toronto. You can contact him by looking up his email address on the University of Toronto website.

    https://sandwalk.blogspot.com/2014/03/a-chemist-who-doesnt-understand.html

    A chemist who doesn't understand evolution
    James Tour is an organic chemist. He is a Professor of Chemistry and Professor, Professor of Mechanical Engineering & Materials Science, and Professor of Computer Science at Rice University (Houston, United States). James Tour is attracting a lot of attention on the Intelligent Design Creationist websites because he is sympathetic to their main claim; namely, that evolution is wrong [see A world-famous chemist tells the truth: there’s no scientist alive today who understands macroevolution].

    Tour is one of the few genuine scientists who signed the Discovery Institute’s "A Scientific Dissent from Darwinism" (2001) that stated, "We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged." (There are very,very, few biologists who signed.)
    more at link...................

    the article concludes thus..............................
    Ignorance is curable. If that's the only problem facing James Tour then he could do no better than read Stephen Jay Gould if he really wants to understand macroevolution. He will get a heavy dose of "pondering and thoughtfulness." I don't think he's up to it. I don't think he really wants to learn.

    Here's why I don't think he really wants to learn about evolution.
    James Tour said................
    "What a comfort it must be to be pleasantly settled in one camp or the other, but I can not be so settled, and hence I have few tent-fellows. Based upon my faith in the Scriptures, I do believe (yes, faith and belief go beyond scientific evidence for this scientist) that God created the heavens and the earth and all that dwell therein, including a man named Adam and a woman named Eve. As for many of the details and the time-spans, I personally become less clear. Some may ask, What’s “less clear” about the text that reads, “For in six days the Lord made the heavens and the earth”? That is a fair question, and I wish I had an answer that would satisfy them. But I do not because I remain less clear.

    I hope that’s satisfactory; I mean for me, a scientist and a Christian, to be unsure of a few things in both science and Christianity. The question is not fundamental to my salvation as a Christian which is based upon the finished work of Jesus Christ, my confession in him as Savior and my belief in his resurrection from the dead. And I used to think that my outward confession of skepticism regarding Darwinian Theory was also of little consequence to my career as a scientist. Specifically, in the past, I wrote that my standing as a scientist was “based primarily upon my scholarly peer-reviewed publications.” I no longer believe that, however.

    In the last few years I have seen a saddening progression at several institutions. I have witnessed unfair treatment upon scientists that do not accept macroevolutionary arguments and for their having signed the above-referenced statement regarding the examination of Darwinism. (I will comment no further regarding the specifics of the actions taken upon the skeptics; I love and honor my colleagues too much for that.) I never thought that science would have evolved like this....

    Hence, by my observation, the unfair treatment upon the skeptics of macroevolution has not come from the administration level. But my recent advice to my graduate students has been direct and revealing: If you disagree with Darwinian Theory, keep it to yourselves if you value your careers, unless, of course, you’re one of those champions for proclamation; I know that that fire exists in some, so be ready for lead-ridden limbs. But if the scientific community has taken these shots at senior faculty, it will not be comfortable for the young non-conformist. When the power-holders permit no contrary discussion, can a vibrant academy be maintained? Is there a University (unity in diversity)? For the United States, I pray that the scientific community and the National Academy in particular will investigate the disenfranchisement that is manifest upon some of their own, and thereby address the inequity."



    I suppose I'm going to be labeled as one of those evil "Darwinists" who won't tolerate anyone who disagrees with me about evolution.1

    I'm actually not. I just don't like stupid people who think they are experts in evolution when they have never bothered to learn about it. Here's my advice to graduate students in organic chemistry: if you want to know about evolution then take a course or read a textbook. And remember, there's nothing wrong with admitting that you don't understand a subject. Just don't assume your own ignorance means that all the experts in the subject are wrong too.
     
  11. Q-reeus Banned Valued Senior Member

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    Allegations that Tour's critique of unguided abiogenesis hypothesis is actually warped and driven by his religious convictions are easy to make and impossible to prove. Exactly the same kind of allegation can be hurled at the mainstream naturalistic abiogenesis community - driven by a pathological need to banish any notion of a creator God. Let's just concentrate on the technical arguments pro and con unguided abiogenesis.

    Professor Dave is actually David Farina, a science popularizer and musician. In the vid he accuses Tour of profound ignorance wrt being able to synthesize the four classes of biological molecules necessary for life - nucleic acids, proteins, carbohydrates, and lipids. Yes, achiral or racemic mixes of molecules in a lab with lots of intelligent guidance at hand is routinely done. He entirely misses the mark though. Within the first minute of the vid I linked to in #13, the same one Farina reproduces in parts, Tour makes it clear the syntheses in question have to be done under assumed prebiotic conditions! Not exactly a small point. What's more, not generating an achiral or racemic random mix, rather all with the correct chirality. Farina goes on to admit that's probably what Tour meant but never specified. False. Tour not Farina is correct in saying that synthesis of chiral molecules under assumed prebiotic conditions has never been demonstrated.

    Farina also ignores Tour's covering the known inefficacy of 'chiral template' crystals yet brings it up anew regardless, inferring such inorganic templates could be viable. No evidence.

    His 'rebuttal' of Tour's pointing out the dilemma faced when source material runs out, counters there would be a huge abundance of feed-stock in the oceans. Probably not but regardless the concentrations in sea water would be far too dilute to allow any realistic ongoing synthesis. Tour's context was the 'warm pond' type where repeated drying then re-wetting at least offered a concentration mechanism. But inevitably a dead end without the all important, 100% efficient chirality generation nowhere seen in (abiotic) nature.

    Another misguided criticism by Farina is the supposed unwarranted criticisms by Tour in his 2019 Dallas lecture, of various claims made by Jack Szostak in his Nature article. I can only charitably conclude Farina was unaware of the article I linked to in #21 that puts it all in proper context.

    Can't be bothered dealing with other liberties Farina takes actually covered and cornered by Tour.

    There is one thing Tour claims I find strange and hugely improbable though - the supposed astronomical number of possible interactome interactions in a theoretical minimal cell. Wikipedia has this to say about the typical number of interactions in a yeast cell: https://en.wikipedia.org/wiki/Interactome#Yeast
    "Yeast
    The yeast interactome, i.e. all protein–protein interactions among proteins of Saccharomyces cerevisiae, has been estimated to contain between 10,000 and 30,000 interactions. A reasonable estimate may be on the order of 20,000 interactions. Larger estimates often include indirect or predicted interactions, often from affinity purification/mass spectrometry (AP/MS) studies.[7]"

    Which is vastly lower than ten to the power 79 billion! The latter may include imperceptibly weak higher order interactions i.e. purely theoretical. Even assuming it is a rare blunder by Tour, it cannot detract from the various other key issues he homes in on correctly. Anyway it's clear from the responses to date minds are well and truly made up so imo pointless to continue arguing back and forth any further.
     
  12. iceaura Valued Senior Member

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    It seems obvious that chiral molecules are generated in all those syntheses - how else could one obtain a racemic mixture?
    I don't see how the efficiency of chirality generation makes much difference. In what way would something like that be "all important"?
    The observer's immediate assumption would be that concentrations of chirality - if needed at this stage of development - would emerge from selection events and circumstances. We know that many clays are chiral, for example, as are certain crystals and the like, all of which spread as small pieces broken from the original and grow while maintaining that original chirality - and any of these would have been excellent foundations for some kind of selection.
    With the caveat that the large body of evidence indicating Tour's faith-inculcated unwillingness to reconsider his apparently arbitrary religious beliefs in the light of evidence and argument, much of it long and in-context quotation of his own writing, does not exist for the "mainstream naturalistic abiogenesis community" - whatever that refers to - and its "pathological need" - which seems neither pathological or needy when specific examples are on the table.
     
    Last edited: Nov 25, 2020
  13. paddoboy Valued Senior Member

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    No one, least of all scientists, need to prove anything. His own words, reveal a fanatical agenda.
    If evidence could be found supporting ID, and/or falsifying abiogenesis, the person finding that would be lauded and be a prime Nobel certain recipient.
    Plus of course the continued finding/s of evidence with state of the art equipment like the LHC, and other devices, point to the hotter, denser universe in the past, the logic of how elements have evolved or are synthesised, how atoms are formed, how atomic nuclei appeared, quarks, the Higg's boson etc......a evidenced based, logical well constructed model, pushing back any need for any ID to the furthest remote corners.
    Even in those remote corners, logical speculation can be used to explain such as the Superforce, the quantum foam, and a universe from "nothing" [nothing being the quantum foam]

    My mind boggles as to why intelligent people then see the need to want to invoke any ID, with their version of the "God of the gaps"
    Fear and a desire for a warm fuzzy afterlife reward, rather then the evidenced backed finality of death, is to some people, a great motivator.
    Agreed.
    Just let me say that these made up minds you refer to, reached that point because of the discoveries and evidence over hundreds and even thousands of years, that the seemingly magical happenings like the Sun rising in the mornings, mighty rivers and mountains spewing fire and brimstone, etc etc, that were all at one time put down to ID or some deity, are all now natural occurrences in a big wide wonderful universe, full of scientific explanations, that we inhabit.
     
  14. Write4U Valued Senior Member

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    You may want to read up on Robert Hazen and why chirality is essential in the evolutionary process.

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    Robert M. Hazen > Quotes > Quotable Quote

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    “Chirality matters. In the curious case of the artificial fragrance limonene, the right-handed form smells like an orange, whereas the left-handed version of this simple ring-shaped molecule smells like a lemon. The smell receptors in your nose are sensitive to chirality, so right- and left-limonene transmit slightly different signals to your brain. Taste buds are less sensitive to the differences between right- and left-handed sugars. They both taste sweet, but our body’s fine-tuned digestive system can process only the right-handed forms. The artificial sweetener tagatose, a zero-calorie left-handed sugar substitute, exploits these properties. The tragic story of thalidomide also rests on handedness. The right-handed version of this drug alleviated morning sickness in pregnant women, but the left-handed variant that inevitably tagged along caused birth defects. Today the FDA imposes strict requirements for chirally pure drugs—regulations”

    ― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

    Read more quotes from Robert M. Hazen

    If you are really interested in what this eminent scientist has to say about chiraity and , start viewing at 12:10 to avoid a lengthy introduction.
     
    Last edited: Nov 25, 2020
  15. Q-reeus Banned Valued Senior Member

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    Sorry my wording not quite right. I meant specified, mostly L-chirality.
    No in practice clays and similar inorganic 'templates' only weakly offset purely racemic mixtures. Nowhere good enough given biological proteins are for the most part exclusively comprised of left handed peptide sub-units. Which handedness is critical for correct protein folding. There is no energetic preference for attachment of left or right handed peptide sub-units to a growing protein chain. Something else has been at work - namely the instruction sets and complex machinery of the existent cell as a whole. Chicken & egg dilemma for unguided abiogenesis researchers.
     
  16. exchemist Valued Senior Member

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    But who says "nowhere good enough" and on what basis? If there is a mechanism to prefer one enantiomer, then we need to look hard at how that preference might become amplified over time. There is no logical reason to give up the search just because we have not immediately found the solution. Science works on a timescale of centuries, not years.

    Tour, if that is who is saying it, tends to bloviate about how impossible it is for "us" to do, (i.e, in the lab, during the professional career of a Houston synthetic organic chemist). How is that of any relevance to processes occurring over hundreds of millions of years, on some part of the early Earth?

    Tour makes no effort to read the abiogenesis literature and then critique it peer-to-peer with the authors. Why? Because he knows damned well he will get blown out of the water. Instead, he takes refuge in leveraging his standing as an organic chemist to convince people with no chemistry background that he is some sort of authority, when he isn't. That is taking advantage of ignorance. It is what charlatans do.
     
  17. Q-reeus Banned Valued Senior Member

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    You are free to be hopeful about the inevitability of some eventual discovery of a wholly adequate enantiomer concentrating mechanism. Just as I am free to conclude such a prospect has essentially zero probability. What would drive such a process on when at any intermediate stage the hoped for protein is wrecked because of random chirality? Teleology creeping in?
    Obviously we come to very different conclusions from the same Tour exposition.
    He never pretends to be an abiogenesis researcher but argues his synthetic chemistry training gives him a unique perspective biologists tend to trivialize - of just how many tightly controlled steps are needed to get a given outcome. Itself producing just one intermediate chemical species, within a prebiotic environment where as he puts it, 'time is not your friend'. To accuse him of being a charlatan is imo misguided at best.

    You earlier claimed his long discussion of constructing a working nano-machine in an earlier article was a waste of time and irrelevant to abiogenesis.
    To me you have entirely missed what he was trying to point out. That the huge multi-disciplinary intelligently manipulated trial and error effort required to finally get a working nano-car was child's play alongside the daunting complexity of even the simplest biological life. Which had to arise in a sparse environment with zero intelligent guidance according to mainstream position. One is then naturally led to ask some hard questions - imo.
     
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  18. Write4U Valued Senior Member

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    Question; What if in the electro-magnetic spectrum there were more negative polar ends than posititive ends?

    Seems to me that the geometric (chemical) properties of chirality are very much like the (electric) properties in the electro-magnetic spectrum.

    Symmetry must be maintained. There is no reason why that should not be so.
     
    Last edited: Nov 26, 2020
  19. exchemist Valued Senior Member

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    Ah, so it was Tour claiming it was "nowhere good enough".

    The nano-machine business is utterly irrelevant. Life had several hundred million years in which to arise. The fact that this guy thinks he can't do it in his lab tells us precisely zero.

    I'm afraid all these objections are just a variant of the Argument from Personal Incredulity: you and Tour can't see how it could have happened naturally - ergo it couldn't. That's not science. It's the God (or "Designer") of the Gaps.

    It's a hard problem in science. everyone acknowledges that. But just because we can't see the answer today doesn't mean there is no answer, especially when you consider the huge progress that is occurring in abiogenesis research. Here is just one recent finding (I quote a tutorial from another forum I belong to). It is a beautiful example of why thinking about it the way Tour does, as a synthetic organic chemist, is completely unhelpful:

    ------------------------------------------------------
    Let us look at the unit of RNA.

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    The picture above shows a DNA and a RNA unit. They are very similar and consists of three parts

    1) A nucleobase (the one with lots of N i.e. Nitrogen groups). In the above picture the nucleobase is Guanine, the (G) of the ATCG letter system. There are 4 others with somewhat different structures.

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    2) The central cyclic pentagonal structure with the O atom at the crown. That is the ribose sugar.

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    3) Finally the Phosphate group (with phosphorus P in the middle) that acts as a bridge linking the different units in a long chain.

    Now the question is how do you make this reasonably complicated molecule naturally?

    For 40 years nobody could do it, and it is instructive to see why.
    1)We have 3 distinct groups and every chemist who looks at it would think that the best way to design such a thing is to make the 3 groups separately and join them together.

    2)Unfortunately for chemists (like me), Nature is not a designer and does not have foresight. Nature does not go about thinking "I must synthesize X-Y-Z at the end; so let me make X then Y and then Z and then paste them together like the proper intelligent designer I am. " Nature, always goes through the path of least resistance, i.e. the path that requires the least amount of energy. And that path is often not how humans would think is logical.

    3)Thus all efforts by chemists for 40 years to make phosphate, ribose sugar and nucleobase separately and then join them together resulted in useless mess of all sorts of undesirable compounds.

    This went on till 2009 (with creationists referring to this failure in glee) when a group in UK (Sutherland group, Cambridge) decided to mix up nitrogen and oxygen chemistry and try to create a sugar-base hybrid in presence of phosphates from the very beginning. And lo and behold, the entire reaction happened quickly and efficiently and created the RNA cytosine and RNA uracil units in just 5 steps and extremely efficiently!
    What starting compounds do we need? They are very simple if completely bonkers:-

    1) Hydrogen Cyanide (HCN) that most poisonous of all gases turns out to be the prime ingredient. HCN is found to form quite a bit in the oxygen poor CO2-N2 rich early atmosphere of earth when high impact meteors and comets were striking early earth.

    2) Formaldehyde (HCHO) and acetylene (C2H2) the simplest of hydrocarbons also created in the atmosphere of early earth by photolysis of CO2 and H2O by the UV radiation of the sun (no ozone layer then) .

    3) Hydrogen Sulphide (H2S), the most ubiquitous gas coming out of volcanoes with the smell of rotten eggs. And ancient earth was much more geologically active.

    4) Water soluble phosphate that was leaching out of the iron-nickle meteors and comets that were falling to earth every month in those ancient times.

    5) Copper and Zinc minerals, widely present in earth, as catalysts.

    6) Lots of UV rays (no ozone layer then)

    7) Periodic wet and dry conditions with temperatures ranging from 40 C - 5 C, very normal even for early earth.


    Under these simple conditions Hydrogen Cynaide reacts with formaldehyde in the presence of H2S and and Copper salts to produce two simple sugars:- Glycolaldehyde (CHO-CH2-OH) and Glyceraldehyde (CHO-CH(OH)-CH2-OH) along with ammonia (NH3) .

    Next Hydrogen Cyanide reacts sequentially with the two sugars above in presence of phosphate as catalyst at 40 C(like sodium phosphate) to create Nitogen-Oxygen hybrid ring structures called oxazoles. These oxazoles crystallize out of the water mixture on slight cooling.

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    (carbon atoms are at the vertices of the pentagon).

    These oxazoles then react with cyanoacetylene (a compound formed by HCN reacting with C2H2) in the presence of phosphate and UV rays to directly create the RNA cytosine and uracil base.

    So very briefly

    2HCN + simple sugars ⇒ Oxazoles (in presence of phosphates)
    Oxazoles + Cyanoacetylene + Phosphate ⇒ RNA units


    The full pathway is shown below for reference.

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    I think the example teaches several things:-

    1) God of the gaps always fails. Even in 2007, the leaders of the prebiotic chemistry field were saying RNA synthesis was impossible . There should be a permanent ban of scientists saying that unless they can formulate a law of physics that supports his case. Just because you can't do it does not make it impossible.

    2) Nature has no foresight. Economy of means ,not neat categorical planning, is the hallmark of natural phenomena. Who would have thought lethal hydrogen cyanide and sugar-base hybrid would be the means by which nature would go about creating the building blocks of life?

    3) In nature, one does not have sterilized labs where only one or two compounds are present at one time. So the way forward is systems chemistry, where most of the reagents are concurrently present and influence the reaction steps through catalytic action.

    I am ending with a brief talk by the lead author of the paper (which should be intelligible now

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    ) and the small fact that in the last 6 years the group has gone on to use those above simple reagents to construct in the lab a chemical reaction cascade that very simply and effectively produces 3 of the 5 RNA/DNA units, 12 of the 20 amino acids and the building blocks of all lipid cell membranes. Thus now its an established fact that 70% of all the basic building blocks that life needs for its RNA-DNA-proteins and cell walls can be easily formed at one go in the prebiotic conditions of the early earth even before any evolution. They can now be created in a space of two days in a beaker with a little heating and cooling and a UV lamp once the way of thinking about how to go about the process changed.

    Here is the full cascade. Its beautiful but would take me a month to explain. The snippet I tried explaining here is the one with the blue arrows (2-3-5-7-9-10).

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  20. Write4U Valued Senior Member

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    Biological Homochirality: One of Life’s Greatest Mysteries

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    Sebastian Wellford
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    Jul 13, 2016 · 7 min read

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    In every life form on Earth, sugars are always right-handed, and amino acids are always left-handed. What does this mean, and why does it happen? This bizarre phenomenon involves chiral molecules and is known as “homochirality.”

    https://medium.com/a-spoonful-of-su...-one-of-lifes-greatest-mysteries-2031f4700c4b
     
  21. paddoboy Valued Senior Member

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    Yes, each side promoting there own agenda....one directed and guided by science and the scientific method, the other directed and guided by the God of the gaps.
    Just as the majority of other scientists argue from their own unique perspective, but without the silly false claim about time not being a friend...It obviously is.
    The other point as I mentioned previously, is that it is notable in his manner of speech itself...upward inflections, downward inflections, increase in the volume in his so called message/crusade, at times to near a shout...maybe not a charlatan per se, but let's say a "well meaning charlatan" aiming to keep his fear of the finality of death in check.
    A daunting, possibly impossible task for scientists in such short time frames...but certainly successful for "mummy nature" over hundreds of millions of years, in a near infinite spacetime, with near infinite content, and the synthesisation of the stuff of life being everywhere we look.
     
  22. Write4U Valued Senior Member

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    And just how many synthetic elements are necessary in the formation of all physics?
     
  23. Write4U Valued Senior Member

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    18,526
    While I subscribe to the importance of micro-tubules, I submit that the self-organization of tubulin dimers into regulatory information networks is perhaps one of the simplest form of self organization. Note that ALL Eukaryotic organisms have micro-tubules "in common".

    Since the formation of earth, the surface area, the length of time, and the available raw minerals , Hazen estimates that the Earth has performed some "2 trillion, quadrillion, quadrillion , quadrillion" chemical experiments yielding all of earth's current chemistry .

    p.s. Hazen does not address microtubules. He concentrates exclusively on the mineral resources and possible chemical reactions that may be obtained from native and extraterrestial resources.
     

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