Aquagem Posted February 4, 2005 Report Posted February 4, 2005 This is just a short synopsis of the state of abiogenesis research as of now. Thanks for the update - citing real science is refreshing!
maddog Posted February 4, 2005 Report Posted February 4, 2005 IDers are adding an additional agent. In order for an additional agent to be brought into the discussion, there must be proofs provided of the existence of this agent and it's method of interaction. Lacking that, there is no valid reason to allow it to be brought into the discussion. Thus they are NOT equally valid.I would say in reverse. For this IDer to prove an additional agent, one must disprove that effect of whatsaid agent would doing could not be explained by some other process. It would be a high standard to"prove" that a said "additional agent" would be the "only" solution. To speculate of what such an agent could do, you have license. Then it based on what you believe or not. ;) Maddog
TINNY Posted February 4, 2005 Report Posted February 4, 2005 For this IDer to prove an additional agent, one must disprove that effect of whatsaid agent would doing could not be explained by some other process.[/QUOTe]please clarify a bit. IDers are adding an additional agent. In order for an additional agent to be brought into the discussion, there must be proofs provided of the existence of this agent and it's method of interaction. Lacking that, there is no valid reason to allow it to be brought into the discussion. Thus they are NOT equally valid.what if the agent is transcendental? I would say that the possibility of its interaction to be through EMR as it is does have special characteristics expounded by the Special Theory of Relativity.About the agent, lets say it is some unknown quality, a black box. One way of knowing it is to try shaking, knocking, smelling etc the black box. Ah, Im stuck..........
TeleMad Posted February 5, 2005 Report Posted February 5, 2005 Fishteacher73: We have crated the amino-groups and early organic compounds neccessary for life in lab conditions much like that of the early Earth. All the parts are there, ... No they aren't. Show me one experiment conducted under prebiotically plausible conditions that formed a single nucleoside triphosphate, the starting building blocks of nucleic acids. Fishteacher73: there is a workable explanation of how they began to fit together. This seems pretty straight forward. No, you're glossing over real gaps as though they don't exist. Fishteacher73: We have a lot of the pieces and this seems to be the most logical way for them to fit together. At least much more logical than some supreme being cooking us up in his oven. As far as the first sentence, might I remind you that you still haven't shown how DNA could form under prebiotically plausible conditions. As far as the second sentence, that's a matter of person beliefs. For someone who already believes in God, there is no new entity being brought into the explanation. In fact, a preexisting entity is doing something that so far nature has not been shown capable of doing. So for a religious person, their position seems more logical. The origin-of-life gap is there: IDists can fill it with the designer, Creationists with their God, and materialists with nature. No one can state as fact that their way is correct: no one can demonstrate his position over the others. All claims of being correct on this are based on pesonal beliefs, overarching philosophical positions, and so on ... not on objective, undeniable fact.
TeleMad Posted February 5, 2005 Report Posted February 5, 2005 Clay has been suggested to play an important role in the formation of the first nucleic acids. it is known that a clay named montmorillonite can create RNA molecules of 50 nucleotides in lenght. The questions remains however, could this take place on the prebiotic earth? There are other questions for this. First, the closest thing to an RNA replicase (self-replicating ribozyme) produced by directed evolution as of about 2002 was about 180 nucleotides long ... and it could copy only about 14 nucleotides, less than 10% of itself. The authors suggested that a true RNA replicase might need to be longer. So at this time, 50-mers appear insufficient to form RNA replicases. Second, the longer the RNA strand, the more tightly is adheres to montmorrilonite (the individual small attractions accumulate along the strand, making the overall attraction stronger). How does the RNA strand get free? One way is to add salt to the solution, but, a high salt concentration decomposes RNA, so this has to be carefully balanced. Third, the experiments circumvented a real problem with RNA called enantiomeric cross inhibition. When both enantiomers (the- left and the right-handed forms of ribose) become incorporated into a growing strand, elongation stops. The experiments that formed 50-mers (and indeed the majority of RNA World experiments that use RNA) use only the "correct" D-ribonucleotides. PS: There are other problems with getting the molecular biologist's dream - a pool of beta-D-ribonucleotides - under prebiotically plausible conditions, but they aren't directly related to the montmorillonite experiments.
MortenS Posted February 5, 2005 Report Posted February 5, 2005 Telemad:First, the closest thing to an RNA replicase (self-replicating ribozyme) produced by directed evolution as of about 2002 was about 180 nucleotides long ... and it could copy only about 14 nucleotides, less than 10% of itself. The authors suggested that a true RNA replicase might need to be longer. So at this time, 50-mers appear insufficient to form RNA replicases. Is it the research performed by the people interviewed in this article you are referring to: RNA-Catalyzed RNA Polymerization: Accurate and General RNA-Templated Primer Extension
TeleMad Posted February 5, 2005 Report Posted February 5, 2005 Is it the research performed by the people interviewed in this article you are referring to: RNA-Catalyzed RNA Polymerization: Accurate and General RNA-Templated Primer Extension Yes, that's the one. Why, has there been a more-recent experiment that improved on this one?
MortenS Posted February 6, 2005 Report Posted February 6, 2005 I believe those experiments are the latest on the top-down approach that is published (at least as I can find. I did find some more articles om the clay montmorillonite. Interestingly, it not only can catalyze the formation of RNA oligomers, it can also catalyze the formation of vesicles from fatty-acids. Also found an article that shows how to produce 35-40-mer long RNA oligomer in just one day on the clay montmorillonite. Much of your critique still applies though, but I am not so sure about the claim that an RNA molecule with a replicase need to be much longer than 50-mer necessarily will hold true. Only the future will tell. One of the reasons why I am a bit sceptical to such a claim, is the relative recent discovery of catalytic activity in very small RNA's (20-60-mer), which includes both self-cleavage and ligation (in molecules of size 40-60. Although no replicase or polymeras has been discovered at such small lenghts yet, these small molecules show that complex catalytic activity does not necessarily require large sequences of RNA. Both the "hammerhead" RNA and the "hairpin" RNA are interesting molecules in that regard. I'm not that concerned about what we have not found out yet. Science will march on, and fill the gaps, one by one. If I have any beliefs at all, that is one of them. It was a paradigm shift that happened once we became aware that RNA had catalytic activity. We have known this for a relatively short time, so the research on the topic is still pretty young (but very active). I think it is premature to state what is possible or not possible at this point in time with regards to catalytic activity of short RNA-segments. Is the glass half-empty or half-full? I'd say it is half-full... Cheers!
TeleMad Posted February 6, 2005 Report Posted February 6, 2005 MortenS: Also found an article that shows how to produce 35-40-mer long RNA oligomer in just one day on the clay montmorillonite. If that’s a literal 24-hour day then that’s 1,440 minutes. With that value, the total number of prebiotic ‘shots’ is lowered a good deal compared to what people usually use in “back of the envelope” calculations. For example, in his estimate of the number of ‘evolutionary trials’ available to the prebiotic Earth, Werner Loewenstein (The Touchstone of Life, Oxford University Press, 1999) used what he called a “super speed” of “1 per minute” per microscopic volume over a period of 900 millions years to end up with a total of 2.25 x 10^48 trials. If we change that rate to 1/1,440 per minute, the value is lowered to 1.56 x 10^45. Not a tremendous drop, but still a good sized one. Further, the number of trials would drop more since Loewenstein’s calculation relied upon “the entire surface of the earth – a surface covered by an ocean 10 kilometers deep, with the chemical building blocks in abundance everywhere.” If we are now limiting trials to just montmorillonite, which did not cover the entire surface of the earth, nor did it at all fill the volume of the oceans, then the number of trials takes another hit. MortenS: Much of your critique still applies though, but I am not so sure about the claim that an RNA molecule with a replicase need to be much longer than 50-mer necessarily will hold true. Only the future will tell. True, no one knows for sure yet. In the 1999 book “The RNA World: Second Edition”, Leslie Orgel argued that a ribozyme would need to be at least 40 – 60 nucleotides long in order to be able to form enough complex structures to serve as a replicase. Even using the lower bound of that range, he stated that the mass of the library needed to get a pair of replicases would exceed that of the Earth. We don’t know that the ribozyme mentioned in the Science article is the shortest possible one, but it is as of today the closest thing to an RNA replicase produced by directed evolution. It gives us the best available estimate of what is required, and it was 189 nucleotides long. That turns the mass of the library of unique ribozymes into being greater than the mass of the entire known universe, let alone the mass needed to come up with a pair of replicases. MortenS: One of the reasons why I am a bit sceptical to such a claim, is the relative recent discovery of catalytic activity in very small RNA's (20-60-mer), … Actually, the smallest and simplest ribozyme known functions not to join nucleotides together to form a polynucleotide chain, but rather it functions to cut nucleic acid chains at specific sites (kind of like a restriction enzyme) – in general, it is destructive rather than constructive... ”… it seems likely that the first RNA or RNA-like molecules to have emerged were small. The smallest true ribozyme described so far is the trinucleotide UUU, which catalyzes, in the presence of Mn++, a specific cleavage between [the nucleotides] G and A (Kazakov and Altman, 1992).” (Noam Lahav, Biogenesis: Theories of Life’s Origins, Oxford University Press, 1999, p192) <spacer> MortenS: … discovery of catalytic activity in very small RNA’s (20-60-mer), which includes both self-cleavage and ligation (in molecules of size 40-60. Ligation is not all that big of a deal. The 189-mer “RNA replicase” mentioned in the Science article started off as a ligase, but it had to be subjected to multiple rounds of directed in vitro evolution and rational engineering before they got it to copy just 14 nucleotides of itself. MortenS: Both the "hammerhead" RNA and the "hairpin" RNA are interesting molecules in that regard. Both the hammerhead and hairpin ribozymes are at least 50 nucleotides in length. That is 25% longer than what Orgel used in his original estimate (which was based on 40-mers), increasing the libray mass by a great deal, and as you point out, neither of these two ribozymes can self-replicate. MortenS: Is the glass half-empty or half-full? I'd say it is half-full... AHA! That’s where you are wrong! It’s half empty :-) PS: I’m a pessimist.
MortenS Posted February 6, 2005 Report Posted February 6, 2005 I have noticed, and pessimists are needed, especially when critiquing the work of optimists. But you would not had much to critique if all the researchers were pessimists. If pessimists had their way, there would be no research into the origin of life on the a priori assumption that life is too unlikely to happen. Only problem for pessimists is that we have life, and we know it happened, just not how (yet). Anyway, thanks for the additional info.
TeleMad Posted February 8, 2005 Report Posted February 8, 2005 If pessimists had their way, there would be no research into the origin of life on the a priori assumption that life is too unlikely to happen. So more scientists would have to work on a cure for AIDS or cancer or any of a number of inherited dieases, or some other worthless cause :-)
MortenS Posted February 8, 2005 Report Posted February 8, 2005 I believe research should be free, and that people should research whatever they want, not what everyobody else want them to research. The best research gets done when you are geniunly interested in your topic. Just to make that clear, I am of the opinion that we should have done research on HIV, even if we we knew there would not be a cure, just for the sake of studying the virus. Until pharmaceutical companies make more money on developing vaccines than developing life-extending drugs against HIV, I am afraid we won't get a vaccine against HIV in a lonh time. I once got a medicine that AIDS patients also receive, and a box of just 60 pills, cost over 2500 USD: Luckily I did not have to pay for more than 60 USD for it, the rest got covered by Social Security.
Lolic Posted February 18, 2005 Report Posted February 18, 2005 I don’t understand the whole hearted buy-in into blind evolutionary forces. For a theory that wants to take credit for so much (or perhaps I over value my brain, heart, lungs, etc. etc) it seems to be terribly lacking in evidence or explanation. Do you truly believe that blind, chance mutation; followed by natural selection is responsible for the integration of your brain, optic nerve, pupil, cornea, rods, cones, etc? That’s a lot of faith in the power of mutations! Shouldn’t we have a right to expect some quantity of transitional fossils, current species in transition, some evidence of species mating and creating new species, etc. if blind evolutionary forces can be expected to account for what we see around us? Don’t we have some right to be apprehensive about evolutionary claims after the frauds that have been perpetrated in the past? The evolutionists’ reaction to Jonathan Wells’s book Icons of Evolution demonstrates why apprehension is justified by the average consumer of evolutionist thought and theory. In that book, Wells analyzes several “icons of evolution.” The reason for calling them “icons of evolution” is that they are presented in high school and college biology textbooks as solid evidence for evolution. Included here are the Haeckel embryo drawings, The Miller-Urey experiment, Changes in coloration of the peppered moth. In every instance, when these icons are carefully examined, they do not confirm evolutionary theory. Haeckel’s embryo drawings, for instance, are now known to have been faked. And yet, these icons continue to appear in the textbooks. What has been the response of the evolutionary community? Has an apology been made for misleading our students?Have the mistakes in the textbooks been corrected?Or have people who question evolution been treated as either, “you’re so dumb” or “you must be a ignorant religious person” or “how could you believe that”. I enjoy looking at the evidence for evolution and for Intelligent Design. But I can’t find good evidence for the first. ID however appears to apply common sense, induction, deduction, philosophical arguments that are relevant, and generally correlates well with the world we see and know. Despite this, the evolutionist seem fearful and emotionally attack ID like it represents higher taxes. No one can force another person to believe something. Why fear the concept? Why not approach it scientifically…can blind evolution account for the diversity, creativity, and complexity we see? Or do concepts like (1) irreducible complexity; (2) specified complexity; (3) design inference have something to add to the debate?
Fishteacher73 Posted February 18, 2005 Report Posted February 18, 2005 Welcome, Lolic! A well thought out and reasoned post. A great thing to see. Do not take this the wrong way, but you have wandered into a forum of some pretty die-hard evolutionst (Me among them) that have debated this many times, don't take it as an attack, but you will in all likely hood get some critisism. Good Luck, and I'll adress a few points. One argument for mutations over ID (for eyes for example) is analog stuctures. Insects have compound eyes, gastropods have a completely different system than the mamals. This implies divergent evolution. A basic mutation (the eye-spot on protists) over time and many generations have new forms. As for transitional fossils, according to the current evolutionary ideal (punctuated equilibrium) specieation occurs very quickly (geologically) when stress are put upon a population. The odds of fossilization are very low, and with the trunckated time period true "transitional" organisms are unlikely. Although one can see many aspects of evolution in comparing various species. Homologous structures abound. Yes, there have been frauds in science in the past, much of the creationist ideals are built upon an institute buldging at the seams with fraud. And science has openly devulged these hoaxes once known. They are still trying to push the Shroud of Turin as a real relic. I have not read the book you speak of, but am familiar with the point that you bring out from it. The Haekel Drawings: While these are considered poor science (The images were not faked, but the scale was ditorted in comparing various embryonic stages) the basic concept represented by them has other evidence in the genetic areana. Miller-Uray experiment is now usualy considered inaccurate. The believe atmospheric conditions are much different than they were when the experiment was conducted. Other experiments using what we think is a more accurate representaion of the primordial atmosphere have yielded amino acids as well. As for the peppered moth, I have not seen anything that reputes the idea of natural selection in this case. The darker variant was able to hide betterand resist predation and thus became the dominant phenotype. There are other arguments against ID, just sift back through the thread and ask what you want. While we might disagree, I think we all agree on looking for the facts.
Tormod Posted February 18, 2005 Report Posted February 18, 2005 Lolic, Fishteacher welcomed you and took care of some of the points. But I must say a head-on attack like yours is not the best way to enter Hypography. It's a bit sad to see such hostility in a first post.
Lolic Posted February 19, 2005 Report Posted February 19, 2005 TormodPlease excuse me. Without realizing it there probably is a sense of hostility inside. I see you are from Norway, I am from America. I’ve been to Europe but not Norway so I can’t comment on your society. In America I’ve seen the social effect of evolution being taught in our schools. Children or young adults who once believed in God, are taught evolution in school, and then feel there is no God or no need for God. I’ve heard quite a few stories from people who said they believed in God until they had Biology or natural science class that taught evolution. The social cost is large. :D The change in moral accountability likewise. :xparty: Ideas have consequences and this one has affected our country. :o Please tell me, how would you have said what I said in a non-hostile manner? :D
bumab Posted February 19, 2005 Report Posted February 19, 2005 In America I’ve seen the social effect of evolution being taught in our schools. Children or young adults who once believed in God, are taught evolution in school, and then feel there is no God or no need for God. Hi! That's hardly evolutions fault, is it? :D The social effect is really a side point, if evolution is correct science. And it really is, at this point. Read through many of the other posts, look it up, etc. I think you'll find overwhelming support for the theory. Now, is it worth it to teach evolution? I think that's the question you are after. From a social point of view- does evolution cause social problems? I think you'll find out no, but data would be interesting- I've heard this idea before, but never any stats to back it up. Perhaps the problem comes from the confusion as to what evolution is talking about, and what your faith is talking about. As a believer and a "evolutionist" (i hate titles), I see no conflict. in fact, that's another thread on the board. What are the social effects you see from teh teaching of evolution?
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