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Abiogenesis Debate i |
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Amstree said: there are many problems with your assertions. this is one simple one: regardless of the 'odds' calculated it doesn't mean that whatever the odds are has to be accounted for BEFORE whatever can happen! Your only objection I suspect is that it contradicts the fairy tale version of science known as evolution – which tells us of how frogs can turn into princes. Mind you that real science is usable, repeatable, and testable - not fairy tales supported by nothing more than wishful thinking. Now let’s look at my problematic assertions. Realize of course that ignorance of mathematical odds do not make the impossible probable. There is an error in your reasoning. First you assume as you are told and have come to believe that chance and time alone will bring into being organic complexity (which by the way defies known naturalistic laws). Second you assume proteins (the building blocks of life) can be assembled by mere combinations of amino acids through trial and error and without direction - disregarding that the assembly of proteins require the use of genetic information to orchestrate the process as all proteins are made in strict compliance to the genetic coding that reside within the DNA molecule of that organism - where lays another enormous hurdle for the chance synthesis of life - the existence of the genetic code. But we will discuss this in further detail later on. if god exists because human 'conceptualize' god then god would not exist without humans?! i think the bible answered this by saying - "in the beginning god created the heavens & the earth." clearly this god is not a concept that didn't exist until humans were created, but existed BEFORE anything was created. even here 'time' was a factor, not 'concept' which couldn't exist until humanity came about. Not god, but God. It seems you have little understanding of the God of the bible at all do you? Realize however I am not here to prove to you God’s existence but to show you the logic behind His existence as He does exist regardless of my efforts as design does demand a designer. But we can save this topic for later. the entire argument is foolish & furnishes nothing except more confusion. thanx for the laughs. A baseless summation I suspect – until it is shown where the argument is foolish your conclusion is very much meaningless. Of course my post was simply an introduction into the main course, for now we get into what is observed to occur in reality. But if there are any confusions then let’s clarify them. But instead of arguing what is observed to occur – speciation or variations within a given kind – lets look at even before the simplest of life can even begin to mutate and grow in complexity – for without the first life there is no mutation or natural selection of any kind, is there? Hello, Crusadar. Welcome to DarwinTalk. Thank you. I hope this turns out to be a productive discussion unlike the other forums I have been to. I will pick on your inaugural post, if you don't mind. First, yes many of the points that you raise are rediculous. But no one believes them. I'm afraid that you don't understand the theory of evolution very much or what it actually says. Here is a short introduction to what evolution is all about - it is possible that you already know all of this; if so, then most people here would be interested in discussing the issues that you still have. Not at all, hominid, that is the reason I posted here, anything posted is fair game – I hope you will feel the same. Your assumptions are correct in that I am a student of science and am familiar with evolutionary theory – but that is not to say I believe in what it teaches as I am a firm believer in the word of God. If you were to ask me the question as to who has the most evidence for the origin of life - creationists or evolutionists, I would say that neither - since we all live in the same universe and look at the same evidence. I hate to sound like I'm being dismissive, but this is not true. Creationists ignore evidence, or try to distort it, or try to make it up. For example, radiometric dating gives ample evidence that the earth is almost four and a half billion years old. I have no feelings to be hurt hominid - if that is what you are concern about. But I do ask that you don’t make assumptions about creationists and then try to fit me into that mold, as I will try not to do the same with you – what I will do however is attempt to have a reasonable discussion about the matter at hand using what is observed – without the use of wishful thinking. And what would be the reason you believe in what you do and I do not? Could it be our underlying presuppositions to begin with? As evolution does require long ages. Of course dating methods are not conclusive in determining anything as one would need to make many assumptions before one reaches a correct guess. Creationists try to discredit this by find a few problematic dates out of literally thousands that consistent, or they make up new science out of thin air, like that decay rates used to be different in the past. What I was pointing out is the fallacy of any argument that is already based on presuppositions that cannot be logically reasoned out nor does not fit the data. Likewise, most creationists seem to believe in a global flood, yet flood deposits are easily recognized by geologists and a global flood would leave very obvious evidence, which geologists simply cannot find. I am not a geologist nor am I familiar with the topic so I cannot comment on it – unlike some I will not discuss that which I am not familiar with. Creationists also try it ignore the vast amount of evidence that really cannot be satisfactorily explained except by the theory of the evolution. I am sure both sides have done quite a bit of ignoring. Let’s not get into our likes or dislikes of creationists or evolutionists or their methods but speak mainly on the merits each side’s claims. As a competent scientist there is no reasonable way for you to say that the Neo Darwinian formula for life works – because it doesn’t. This has been proven numerous times over. I have seen many examples of purported "proofs", but every one I have seen either makes some logical fallacy, or ignores easily available scientific evidence. I am sure that you have, but again show me where it is my reasoning is fallacious. The point that I was making was that much of what is discovered by origin of life researchers have proven nothing and yet they attribute that it certainly proves that life was not the result of a creator but the result of an unguided process. However keep in mind that evidences are not found with labels attached - they are given interpretations based on either an a priori commitment to materialism or from a biblical view point. Dr. Sidney Fox and Dr. Stanley Miller (evolutionists of course) were among the first scientists who attempted to prove abiogenesis. Actually, what they set out to prove is that organic molecules, usually assumed to be associated with life, can be made from inorganic materials by abiogenic process. They did, indeed, prove that very thing. What they did prove was nothing of how basic substances could have assembled itself into life but that it would require not only the defiance of astronomical odds but that impassable barriers need crossing before any combination of these basic substances can be considered life. Does this prove that life could eventually have arisen in some soup struck by lightning? All this experiment intended to do was to show that the first step is possible. It did so. To be exact, it rather revealed quite a misunderstanding of biochemical processes as what was produced by such methods was of such quality that no life would be able to assemble itself from such – even with intelligent guidance. The exact contents of such experiments shows as follow: 85% of the product was a brown, insoluble tar or "polymer" made of hydrocarbons and other atoms interconnected in an irregular mass, with no known biological relevance to the origin of life. A chemist in a laboratory might be able to set up the right conditions to convert the "tarry sludge" into biogenic compounds such as amino acids, nucleotides and lipids, but there is as yet no indication that such conditions may have existed anywhere in nature. 4% of the product was the simplest and smallest of the carboxylic acids, formic acid (comprised of just five atoms) which is found in good concentrations in ants, but has no known role in the origin of life. 2.7% was equal parts (0.9% each) of three more caboxylic acids(not amino acids), which are different arrangements of 13 atoms (3 carbons, 7 hydrogens, 1 nitrogen, and 2 oxygens), and have no known or conjectured relevance to the origin of life. 2.1% was glycine, which is possibly significant, because it is one of the 20 amino acids, which are used in biology to construct the proteins of living organisms, glycine is the simplest. 0.85% was the Left-handed form of the amino acid alanine. Alanine is also one of biology's 20 amino acids, the second simplest, which is produced in both of it's mirror-image forms (of stereo-chemistry), where only the left-handed form is used by living things, 0.85% of the product was the right-handed form which is also produced, but is destructive to the proper construction of life. 0.5% was acetic acid, another carboxylic acid, which gives vinegar its pungency, but which is (so far as anyone knows) irrelevant to origin of life processes, 0.026% was another simple amino acid (in its useful L-form), which is only 260 parts per million of the product. Several more of life's 20 amino acids were produced in ever smaller trace amounts, and only half of each of those trace amounts is the useful L-form. Recently, trace amounts of the five bases of DNA and RNA have been detected ...but only about 2 parts per million. On the other hand, even though the chemicals were present for the production of a "nucleoside" (which is the combination of a DNA base plus a sugar), no nucleosides have ever formed in any amount. Furthermore (of course), a nucleotide has never formed, which would require the addition of a phosphate onto the nucleoside and the nucleotide is actually the basic building block of DNA and RNA. - Ref. ORIGINS: A Skeptic's Guide to the Creation of Life, by Robert Shapiro, N.Y., Summit, '86, p.104,108. There is no known life that can use a combination of both "right-handed" and "left-handed" amino acids. Adding even one "right-handed" amino acid to a chain of "left-handed" amino acids can and will destroy the entire chain. There are recent experiments and theoretical work that shows that this problem may be avoided. And what experimental methods may I ask were used that can be repeated and tested that can confirm this? Every test known to have been done by such methods have resulted in a racemic gunk that is useless in the synthesis of life. but life requires much more than just simple amino acids, it also requires proteins and DNA coding or instruction to assemble all the amino acids that reside within a living organism. Our form of life does. It may be that there are other hereditary and biochemical mechanisms that can form self-replicating systems that we would call life. Is there really reliable proof that this has not always been the case? Where if there is evidence that such mechanisms exist even to this day that is able to assemble proteins without genetic instruction? What chemical paths were taken that such mechanisms can retain and passed on these systems to succeeding gernerations? One chemist has calculated the immense odds against amino acids ever combining to form the necessary proteins by undirected means. This is the problem. Evolution is anything but an "undirected means". I will concur that it is not with randomness that species can change – it is with guidance of genetic information that already exists. That is not what is being disagreed on. What is being disagreed on is how such changes can occur where there is no method or means of retaining the increases of complexity required for evolution to occur. And even if you do manage to replicate all the necessary enzymes by chance, First, all the enzymes do not need to arise all at once. All you need is a self-replicating system - it can be pretty simple one, and is inefficient, and is not a very good replicator. But through evolution, selecting better and better replicators, not through chance, bits and pieces can be added, modified, and gradually evolve to what we would call the earliest cell. That may be more wishful thinking than real science at work here hominid. What you do not find are such simple systems anywhere in existence today – and mind you evolutionists have looked very hard and have had a very long time to do so – like over a hundred years since Darwin’s demise. Speculating of course that there is such a simple creature, much more simple than even the simplest self reproducing organism Mycoplasma genitalium, which has the smallest known genome of any free living organism and yet contains still 482 genes comprising 580,000 bases. However this organism’s genes are only functional with preexisting translational and replicating machinery, a cell membrane, etc. - as it can only survive by parasitizing more complex organisms which provide many of the nutrients it cannot manufacture itself – now to consider a creature with lesser parts than which is known to require seems more bankrupt than accepting what logic and reality tells us. Let us compare the amino acids to pieces of a puzzle. Now the puzzle is a picture of Leonardo’s “The Mona Lisa.” Weak analogy. This is nothing like evolution works, or what it says. Of course it is not how evolution works - it is the step before evolution can occur, for how can you reach step two when step one can’t even be reached? The analogy represents simply one of the many theories proposed to have been the path taken for the first life to have come into being. This shows every sign of design and not from natural unguided processes or through a series of accidents. There are no unambiguous signs of design, and evolution is not an unguided process or series of accidents. Then what or who guides such a process? Certainly it isn’t natural selection since natural selection only works where there is something to select from. It may be that you are perhaps in denial of what you see. It is from reality we understand that that which is designed reflects the capabilities of its designer. For it is that the more we dig into the mysteries of life, we find that it is infinite much like its designer is said to be. The purpose of DNA is like a computer program stored on a storage medium where the encoded information and instructions are able to be read from and used as a blue print in the construction of life. Perhaps, but this analogy can only be extendes so far before it breaks down. DNA is not a computer program, and cells are not computers. And yet this is what is observed to occur. An argument from what is repeatedly observed to take place is worth much more than pontifications that cannot be proven. It is estimated that the DNA coding that resides in a human cell stores enough information code to fill 1,000 books – each with 500 pages of very small, closely-printed type and would require a good typist over 2.5 years to type it out if she typed 24 hours a day and 7 days a week for the entire time - if the mistakes are kept. And yet cells are able to do this within minutes with little or no mistakes! Irrelevant to the idea of evolution. You have just "proved" that DNA cannot replicate on its own. But it does. In a few minutes. It does so by replicating many parts of itself at the same time. This is called "multi-processing", to use your computer analogy. This is actually seen in a laboratory. How is it irrelevant when evolution requires that DNA already be present in order to increase in complexity from one generation to the next? What is proved is that cells are already programmed to replicate DNA, as it is dependant on this instruction. As such cells cannot replicate without that which it is dependant on and cannot acquire. What are the chances of DNA molecules which are crucial to all life evolving by natural processes and without any intelligent input from a designer? If the natural processes include natural selection choosing the most efficient replicators, pretty good. You forget that natural selection only takes place where there is DNA to select from - without genetic information there is no selection of anything. Many scientists are convinced that cells containing such a complex code and such intricate chemistry could never have come into being by pure, undirected chemistry. Exactly! Now your getting it! And so you. The idea of a Creator isn’t so difficult to grasp now is it? No matter how chemicals are mixed, it does not create DNA spirals or any intelligent code whatsoever. Only DNA reproduces DNA. Now if you think this could of came by chance you obviously need psychiatric help. Exactly right. No one thinks that DNA came about simply by mixing chemicals. And yet it is what evolution teaches, that life requires no guidance of any kind as it did come into existence on its own - to include the genetic codes that are very much a vital part of all its vital functions. According to most Evolutionists, the universe is less than 30 billion years old Actually, less than 15 billion years, probably less than 12 billion years. And the earth itself is less than 4 and a half billion years, and was only habitable for maybe a little over three and a half billion years. Of course there is no undisputed proof of this is there? Even if nature could somehow have produced trillions of genetic code combinations every second for 30 billion years, the probabilities against producing the simplest one celled animal by trial and error would still be rather quite improbable! Clearly this is not how nature produced the simplest one celled animal. And how may I ask did nature produced these organisms? Based on evolutionary explanations the origin of life could not have happened by chance. Exactly! How? Through natural selection acting upon beneficial mutations over vast time spans? How again did it do that when there is nothing to select from - as mutations can only occur where there is already something to mutate. Mainly the Law of Biogenesis - that only life begets life. There is no such "Law of Biogenesis". Is this not what is observed time and time again or does life magically appear from thin air? Last I remember only life reproduces life. We now know that science has produced stronger evidence against life having arisen as a result of unguided random processes, but through careful thought and design. Science has produced no such thing. Denial at work. It is simply another excuse to turn away from God and His final judgment. Many Christians believe that evolution is how God did the creating. There is a major problem with theistic evolution as it contradicts with what scripture – the basis for the Christian faith – as one does need to do quite a bit of mental gymnastics to make God fit into evolution – for one the time line does not fit. There is a difference between believing in the god of evolution and the God of the Bible. The difference is that if God created us as He has revealed to us in scripture then that would mean that He sole proprietary rights to us, and therefore we are subject to His laws and judgment. But if we came by chance or any other way then who really owns us? If we were the result of a process why even worry about an after life since death is the end of this reality? For if you believe that there is no God to hold you accountable for everything that you do then why not do exactly what your basic urges tell you? Perhaps. My basic urges tell me to be nice to people, to help them, and to avoid harming them. Or the conscience that a wise Creator has placed in you to know the difference between good and evil? Much like Jeffrey Dahmer, the notorious serial killer, in an interview with Stone Phillips said: Now you are being offensive. First, many Christians accept evolution, so evolution does not lead to atheism. Secondly, as an atheist, I can assure you that atheism does not make one into a serial killer. Many serial killers blame their crimes on their Christian-derived religious beliefs. Anyone can use any religion/philosophy as a justification of their crimes. I made no such comments that Dahmer was an atheists nor that atheists are without morals – only that without an absolute code of conduct given by God there is no basis for any morality – as morality would be simply a matter of opinion so what is to say one person’s version of morality is more valid than another's? And it would seem you may know of Christianity but not what it teaches. God and evolution do not mix, for those who do so compromise the many scriptural truths. One such truth is that the God of Christianity is omnipotent and omniscient. What glory is their in creating through such a slow and cruel process as that of evolution? In saying that God used evolution it blames God for the struggles, mutations, death, suffering and the many other atrocities in the living world – for this is the mess that we see today (a consequence of man's rebellion, not God's creative process). What demented god would use such a cruel process where the weak die and the strong survive? How can this be when Jesus himself said "come to me, all you who are weary and burdened, and I will give you rest. By such a cruel process one does not conclude that this shows a God of love as scripture clearly tells us. It shows rather a cruel ogre like god who enjoys seeing his creation tormented and tortured. Does God not also promise us relief from death and suffering in the good Book – but how can that be since it is the very process He used in creating us? After all He is simply allowing us to evolve into better beings so why bother to even pray for relief from it? If they are the Christians they claim to be, they would allow faith to guide their reasoning for God is the God of Truth and He does not lie. If they cannot accept what God said about creating the world as He claims He did, then it is obvious that He lied, so what makes them think He did not lie to them elsewhere in the Bible? After all what logic is there in believing a God that lies? Most atheists believe that since we are all here only for short time, with no afterlife, then we are obligated to cherish the lives of others. On the contrary, in a footnote to his Descent of Man, Charles Darwin wrote: ‘Nor is it probable that the primitive conscience would reproach a man for injuring his enemy: rather it would reproach him, if he had not revenged himself. To do good in return for evil, to love your enemy, is a height of morality to which it may be doubted whether the social instincts would, by themselves, have ever led us. It is necessary that these instincts, together with sympathy, should have been highly cultivated and extended by the aid of reason, instruction, and the love or fear of God, before any such golden rule would ever be thought of and obeyed.’ Finally, I will point out that your entire post is about abiogenesis, not evolution. Even if you can prove that abiogenesis is impossible, that the very first life form had to be specially created by a sentient being, the evidence still demonstrates that all present and past species descended from that first life form through natural selection. You have said nothing that disproves evolution itself. And thus I respond that the entire post points out the circumventing that has been done to sweep under the rug the logic that life from no life is an is possible when in reality it is an impossibility to the highest degree - as such ignorance of this fact will not make possible that which is not. It is always assuring to know that life was the result of simply a sentient being, space aliens or the like and not God – as the god of evolution or any such method which is incompetent at designing anything brings no indigestion as much as a God who has total control over what He has created - who made absolute laws that His creation will be judged by in everything that it does – I guess to many that is simply unacceptable. Sorry for the late response, but work always takes precedence over play. Time only permits me to respond to serious posters once or twice a week as I find it more rewarding to reason things out than just being dogmatic and show no reason for what one believes but regurgitate popular opinion (which is not science) – as some of us here are doing. Hominid said: Unfortunately, you seem interested in abiogenesis. It is a topic that I don't know much about, and to engage in a discussion on this topic would require me to do more research than I have time for (I am in my last year of grad school and need to be job searching and finishing my dissertation). On the other hand, there are people here who do know quite a bit about the subject, and they might be more interested in carrying on the conversation. I know I would be interested in learning more about this, and this time I will pay attention (heh). It is a dry subject indeed, the hard sciences, in which not too many are able to understand fully nor participate in a intelligent discussion. I however do not claim to be an expert in the subject but have researched it enough to understand that life was the result of a creator and did not come about on its own. I hope that there are others who are versed in this field from the evolutionary viewpoint as I am interested in what they have to say about the topic. That said, I will now contradict myself by commenting on a few of your points. First, there is evidence that the chirality problem can be overcome. There is experimental evidence that chiral self-replicators can arise and reproduce in a racemic mixture. Now when you read this article, I think I can predict an objection that you will make (despite your protests for me not to fit you into any mold, heh). Of course, your predictions are correct. You will likely point out that the fully formed chiral polypeptides were added to the mixture, and didn't just spontaneously come about. Exactly my point hominid, for any such experiment to be attributed to have been the path taken to solve the chirality problem it must be purely spontaneous. It must be independent of all intelligently controlled factors, for you should realize that most if not all intelligent experimental interferences rob us of the right to call such an experiment “spontaneous”. This is a fair objection, of course. But this is the way science works. I am familiar with how science works. It is only when it is attributed to represent something that does not then it is no longer science. There is a problem that needs to be answered, so the problem is solved one piece at a time, sometimes starting in the middle of the proposed process. The question here is: How can chiral molecules arise and reproduce in a racemic mixture? Well, scientists have now answered on small part of the question. I would hardly conclude that they have solved any part of the question as it has been around quite a while - what they do know however is that life is even more complex than they thought it was. Now the work is to get the answers to the rest. Science simply does not just throw up its hands and say "I don't know! I give up! That of course is not what I am suggesting at all. It is when such findings (acquired through pains taking work) are all attributed to being part of a blind process. The question is unanswerable!" Science rolls up its sleeves and gets to work finding out the answers. And its success rate is admirable. We know more about abiogenesis than anyone ever thought possible 50 years ago. And the our knowledge is increasing. And what conclusions does science extrapolate from such findings to tell us as to have definitely been the case? That the process leading up to the formation of life requires no intelligence at all to guide it, when scientists themselves are so intense in the process and now they can definitely conclude that it all came about on its own? Incidentally, note that in the article the polypeptides were quite small. And so were the polypeptide chains – considering that the average protein consists of about 400 amino acids exclusively of the “L” form - I might add. Is it too improbable for such molecules to arise naturally? Here is a link on the fallacy of probability calculations concerning abiogenesis. I myself think the probabilities are a gross underestimation of what natural processes are capable as there are astronomical factors to be just right - so many in fact that it would require an even bigger faith to believe in, as it already excludes the miracle maker - God. As I said, I am content to say I don't know much about the origin of life. The science is still in its infancy (think how little we knew about chemistry even 200 years ago!). But I find the amount of progress impressive. So we don't know all the answers yet. So what? There has been a lot of progress in finding the answers. Nor do I - know that much about it. What I do know is that the Word of God tells us that life was the result of a creator God. And no amount of research will refute that – as the more we dig into the mysteries of life – it rather confirms that intelligence (or an infinite intelligence) was needed to create it. My main interest is in the evolution of life after the origin. Although I am not a researcher in the field, I like to think I know quite a bit, and I do enjoy learning more - that is what I like about these discussions, is that it forces me to learn more. I also have done some work in science, so discussion of the philosophy of science don't frighten me either (in fact, I am in the middle of one on another message board). If you want to discuss the theory of evolution, which, technically does not include abiogenesis in its domain (although I am sure that the first not-quite-living imperfect replicators must have undergone natural selection), then I would be more likely to take the time to discuss the issues. My interest in creationism or evolutionary debates such as this are simply a by product of putting bread on the table. My main interest however to proclaim the truth of God. One criticism I do have with your response to me is that you used the words "information" and "complexity". Unfortunately, I have never seen anyone actually define rigorously what these words mean, nor make a logical argument how these concepts preclude evolution. Perhaps we can discuss further these concepts when time permits. To roughly explain the terms – evolution requires an accumulation of complexity from simple life forms to complex ones. However in order for this to occur – new information (in life it is known as DNA) must be created, retained and passed on from one generation to another. This however is not seen in nature, information is not created at all, but merely the reshuffling, or suppression of existing information that results in – the changes that are so called - microevolution. These concepts came about in the light of information theory which I am only beginning to research. Not being a Christian myself, it is not for me to state whether the theory of evolution is consistent with Christianity. That is for those who are Christians to argue this with you if they wish. However, I will impart an anecdote. When I was at the University of Colorado, one of my fellow students was Baptist. I don't think he was fundamentalist, but he certainly was conservative. I asked him about what he thought about evolution, and he didn't want to discuss it. He said he didn't know much about it, but he simply wasn't interested in it. He said it just didn't matter to him at all one way or another since he didn't think it was a salvation issue. Really, one must separate what one believes about Christians or Christianity, but look on it as being the belief of the individual which cannot be attributed to being representative of Christendom. It is true that the question of salvation does not rest on creation being true or not – it ultimately rests on whether one has accepted Jesus Christ as their personal Lord and Savior. However here is a quote that explains why I do not and cannot believe in evolution: “Christianity has fought, still fights, and will continue to fight science to the desperate end over evolution, because evolution destroys utterly and finally the very reason Jesus’ earthly life was supposedly made necessary. Destroy Adam and Eve and the original sin, and in the rubble you will find the sorry remains of the Son of God. If Jesus was not the redeemer who died for our sins, and this is what evolution means, then Christianity is nothing.” - G. Richard Bozarth, ‘The Meaning of Evolution’, American Atheist, p. 30. 20 September 1979. Finally, as far as your comments about morality in an atheistic world, well, as I said, since evolution does not imply atheism, that is technically not relevant to the discussion. I don't mind discussing it, but it should probably be in its own thread. Take a look at older threads - it may have already been discussed here. But be careful - many people start too many conversations on too many topics and realize they can't keep track of all of them (although you said you are a veteran poster, so you are probably aware of this). There is really no one answer to the problem of morality, but reality does tell us that without an absolute code of conduct from a divine law maker morality is simply relative and what is to say one societies moral laws are more valid than others when there is no basis for such laws except what is popular opinion. On the contrary evolution does not require God, not only does scripture mention nothing of it – it goes against all that God represents – that however is another topic. You did a good job, hominid, in explaining the required chiralty of life’s building blocks in terms that can easily be understood. However it takes rather some understanding of how life’s processes work in order to appreciate the intricacies required to, should we say, make life “go”. Sometimes by over simplifying life’s processes we get the impression that it is not as complex as it really is – and therefore could have been the result of unguided natural processes. hominid said: The problem that Crusadar is pointing out that in cases where simpler, chiral molecules can spontaneously combine into large chains of molecules (like amino acids into proteins, or nucleic acids into DNA/RNA), you usually need a mixture of pure chirality - as you start the chain, once a molecule of the wrong chirality gets attached, it gums up the works, and the process of macro-molecule growth stops. The problem with an over simplification of the chirality requirement for the synthesis of life is that it tends to be dismissed as posing no difficulty at all in the synthesis of early life (if you believe there was such a creature) – it is all but a matter of time, and given plenty of it, and right conditions, what is to say life could not of came into being on its own, as we can clearly see that we are the result. Well, for one repeated observations from reality tells us that it won’t because it can’t. The flaw with such an argument that the problem was solved “because as you can see here we are” is that that it makes assumption about natural processes that does not occur. It postulates erroneously that amino acids of the laevorotary or left handed form and dextrorotary or right handed forms are able to chemically attract its own type when it can not. It is a fact that there are no chemical distinctions between “L” and “D” form amino acids of the same type as they are exact in chemical composition. The only distinction between the two is that one is a mirror reflection of the other – which can only be seen optically – when polarized light is passed through the tetrahydron like structure of its carbon atoms making the light rotate either to the left or right. The separation of the two left to natural process will produce no pure mixture of either form whatsoever. Tests and experiments to date have produced exactly that - a racemic mixture of the two. Experiments to produce a pure mixture of the two through natural processes have become so predictable that it has in fact become a law in biochemistry (at least the book the following quote is from anyway). “Synthesis of chiral compounds from achiral reagents always yields the racemic modification.’ and ‘Optically inactive reagents yield optically inactive products.” Morrison, R.T. and Boyd, R.N., 1987. Organic Chemistry, 5th ed. Allyn & Bacon Inc. p.150. The synthesis of life is dependent on a pure mixture of left handed form amino acids as cell metabolism requires a lock and key fit to such an extent that a single right handed form amino acid existing in a chain of l form amino acids prevents the hand and glove fit that is required for metabolism to occur. Since cell metabolism requires that long chains of left form amino acids fit into its respective left form gloves - to the exact fit - any adventitious right handed form will bring metabolism to a complete halt. It is no surprise at all that life cannot use right handed forms as it will never produce the glove like fit required for metabolism! hominid said: The polypeptide that they used was only about 31 amino acids long - considering the size of the oceans, and the amount of time possible, is doesn't seem all that unlikely that such a protein may have come about by chance. Some understanding of biochemical process often helps, however since you are not familiar with as you have pointed out I will attempt to explain why the oceans would be the last place for life to have had evolved. In chemistry there is a law known as “the law of mass action”. In the formula Stanley Miller - a contemporary and colleague of Sydney Fox used
Step 1.
In the above formulas, on closer examination there is a reversibility factor in which the reactions can occur forward or backward depending on experimental conditions. That is the direction of the reaction depends on the concentration of reagents on both sides of the formula. If the water molecules that are formed or released during this reaction are removed as soon as they appear then the reactions will in no doubt shift toward the right hand side and thus the theoretical yield of peptides are obtained. If however the water molecules produced are not removed and there is a large amount of water present then no peptide or very few will be formed as equilibrium always remains on the side of the initial reagents or amino acids. This is a well known fact of organic chemistry that amino acids will combine only in the smallest amounts if they combine at all in a primordial ocean containing excess water where any chain of amino acids which might be formed will be broken down into their initial parts by excess water. Late response again, oh well, you know how busy teaching can be – with tests to grade, papers to read, lessons to plan for and so on. However I won’t bore you with the details - anyway lets get to the fun stuff. If however the water molecules produced are not removed and there is a large amount of water present then no peptide or very few will be formed as equilibrium always remains on the side of the initial reagents or amino acids. hominid said: This is not true. If large amounts of hydrogen were mixed with equal amounts (in volume) of oxygen, with appropriate energy source, then essentially all of the oxygen will react with half of the hydrogen to form water. The initial constituents will not be favored. Um, are we taking about the same thing? i.e. peptide formation. Which side is favored in a chemical reaction depends on the reactents. Not so in reactions that are reversible as the chemical reactions of life are. Even when the correct conditions are met and the amino acids do bond to form peptides prevents the steps required for the peptides to become the building blocks of life. Almost all biochemical reactions, to include the formation of amino acids into protein chains, are governed by equilibrium - as such biochemical reactions are reversible. In a prebiotic environment as speculated to have been the case for amino acids to have formed into protein chains - there is nothing that exists naturally that would prevent the chains from breaking up into their initial components. As such the formation of proteins from amino acids cannot be likened to the random typing of letters onto a blank page as many have postulated. Yes, the random typing of letters on to a page makes the letters stay where they are placed. However, amino acids are not the same in that life requires the typing in and typing out of its reactions. In fact the reactions of life rather types out much faster than it types in – due to the second law of thermodynamics. I do not know the situation for polypeptides - are you suggesting that under the given conditions all polypeptides that are formed will immediately disassociate? I find this hard to believe just from my knowledge of general chemistry. If the energy source were localized, say lightning or hydrothermal vents with suitable catalytic minerals, then I can easily imagine that many polypeptides of relative large complexity can form until they reach some sort of non-zero equilibrium. Under natural conditions yes, peptides that are formed through natural processes break apart much faster than it is able to combine. From what is currently known, raw energy can only be harnessed and made useful with know how (mechanisms and machines) and cannot be made useful any other way. It is well established that raw undirected energy introduced within a system is only useful when it is refined or rectified within that system if the total order of such a system is to increase. However rectified energy is exclusively the product of mechanisms and machines. This fact is relevant to all living and non living systems - the only difference between the two being that living systems are programmed genetically to direct raw energy. As such the genetic program required for directing the use of raw energy is a requirement before any complexity can arise, as then the harnessed energy can be used to finance growth and replication. Are there any experimental results available that are relevant to this question? "The amino acids not represented in proteinoids in the proportions usually found in proteins were cystine, serine, and threonine. These latter were largely, although not entirely, decomposed." (Molecular Evolution and the Origin of Life, Sidney W. Fox and Klaus Dose, W. H. Freeman and Co., 1972, p148) "Sidney Fox found that by heating and drying a mixture of amino acids, and then dissolving the mixture in water, he could obtain strings of amino acids displaying weak catalytic activity. Unfortunately, however, the amino acids were linked in a variety of different ways, and not only by peptide bonds.¨ (The Origins of Life: From the Birth of Life to the Origin of Language, John Maynard Smith & Eors Szathmary, Oxford University Press, NY, 1999, p 32) “Since peptide bonds are thermodynamically unstable in aqueous solutions, once a primitive proteinoid arose, it would be highly susceptible to hydrolytic breakdown in the warm primordial sea. Thus no single proteinoid molecule could be expected to survive for long. This fact raises a fundamental problem. It is difficult to see how any given proteinoid could have undergone residue-by-residue evolutionary improvement to an amino acid sequence better able to survive if each proteinoid molecule lasted but a short period and if there were no means of recording or replicating the amino acid sequence of the “better” proteinoids. This follows from mathematical considerations alone. In all the organisms known today there are only about 10^12 different types of proteins, whereas over 10^300 different types of proteins can theoretically be formed from 20 different amino acids.” (Biochemistry: Second Edition, Albert L. Lehninger, Worth Publishers, 1975, p1041) This is a well known fact of organic chemistry that amino acids will combine only in the smallest amounts (- if they combine at all in a primordial ocean containing excess water where any chain of amino acids which might be formed will be broken down into their initial parts by excess water.) I am always suspicious of "well known facts" (unless I know them, of course). Does this take into account the immense size of the oceans? The presence of possible mineral catalysts? The immensity of the ocean has no bearing on peptide formation that would eventually become a usable protein - as protein formation does not form spontaneously in a solution containing simply amino acids no matter how big the pool may be or how much time is given. This very fact is one of the many reasons why writers of chemistry textbooks are assured their jobs. Take for example this quote from a chemistry textbook: "How did these small prebiotic organic molecules grow into large polymeric substances such as peptides, RNA, and so on? It is important to recognize that by whatever reactions polymerization occurred, they had to be reactions that would occur in an essentially aqueous environment. This presents difficulties because condensation of amino acids to form peptides, or of nucleotides to form RNA or DNA, is not thermodynamically favorable in aqueous solution." Roberts, John D., Marjorie C. Caserio, Basic Principles of Organic Chemistry, 2nd ed., W.A. Benjamin, Inc., Menlo Park, p. 1284, 1977. From experimental evidence it is observed that the concentration of amino acids decreases as amino acids form dipeptides, tripeptides or polypeptides. This decrease in concentration causes the time required for peptide formation to slow down - as a result those peptides that have already combined will begin breaking down becoming single components again. If however more amino acids are added to the solution or if excess water is evaporated from the solution, the equilibrium will be shifted in the direction favoring the formation of polypeptides that can be several amino acids in length - as according to the law of mass action. Equilibrium is reached in such a mixture when there are just as many peptides that have combined as there are those that have not combined or has been broken down into their initial parts. It is possible that a small fraction of the dipeptides can combine with a third or even a fourth amino acid to form a tripeptide, and polypeptides. However the larger the chain of amino acids becomes the more likely that the longer chains will disassociate and be broken down – unless of course there are as you call it “catalysts” to speed the process up or keep the polypeptide chain from breaking apart before it can combine to become a usable protein – to this day nothing of the sort has been found to exist. Time is portrayed as a friend to evolution as it is postulated that peptide formation from a few amino acids to a usable protein and on to the first primitive living organism took many millions of years. Time however is no friend to the formation of peptides. Time rather is the enemy in that it allows entropy to destroy the order that may have arisen by chance - as primitive proteins (let alone actual proteins) are simply not stable enough to remain intact for the length of time as required by evolution. Present day experiments shows us exactly what happens when proteins are left in a petri dish or test tube – they decay and break down into basic substances, it does not organize itself into any form of life. In the process required for synthesizing proteins in present day life, a precise sequence as dictated by genetic instruction is adhered to and is not the result of randomly organized amino acids at all. There exists no proof at all that what exists today has not always been the case other than mere speculations - as protein synthesis is entirely dependant on genetic instruction. In order for non living chemicals to form itself into a self-reproducing organism it needs to create of a large amount of information – to pass on this information to future generations as to not become extinct. Such an organism must not only be able to perform many essential chemical reactions in the correct order, place and in the exact amount - which require specific enzymes to do so, it must also be capable of creating the information needed to produce these enzymes. What is perplexing is that such needed enzymes are coded for synthesis in the genetic code. Not only is the order of amino acids for protein synthesis coded – for the coding to work it requires that there are at least 50 proteins for the necessary decoding in order for the code to be translated. It is rather a matter of intellectual dishonesty indeed to believe that such an intricate language system could have been the result of mere random processes – when observations from reality tells us that language systems and codes are the product of intelligence. An interesting comment made by the late Sir Karl Popper, a science philosopher reads: “What makes the origin of life and of the genetic code a disturbing riddle is this: the genetic code is without any biological function unless it is translated; that is, unless it leads to the synthesis of the proteins whose structure is laid down by the code. But ... the machinery by which the cell (at least the non-primitive cell, which is the only one we know) translates the code consists of at least fifty macromolecular components which are themselves coded in the DNA. Thus the code can not be translated except by using certain products of its translation. This constitutes a baffling circle; a really vicious circle, it seems, for any attempt to form a model or theory of the genesis of the genetic code. Thus we may be faced with the possibility that the origin of life (like the origin of physics) becomes an impenetrable barrier to science, and a residue to all attempts to reduce biology to chemistry and physics.” - Popper, K.R., 1974. Scientific Reduction and the Essential Incompleteness of All Science. In Ayala, F. and Dobzhansky, T., eds., Studies in the Philosophy of Biology, University of California Press, Berkeley, p. 270. Why the reference? What is obvious from the above quote is that a conclusion which can be plainly drawn is that both the genetic code and the proteins and translation mechanisms needed to translate the code must have been functional from the beginning, or there is no life – in other words created in full working order by a Creator.
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Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created. Revelations 4:11 KJV
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