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  • Originally posted by macguy View Post
    So what would be your response to that? I am not entirely aware of how protein folding argues against evolution as of yet...
    Neither am I. In the past I have asked Bob for evidence of a mechanism that would stop many micro-evolutions from becoming a macro-evolution. Protein folding was one response he gave. He did not make it clear how this would prohibit macro-evolution.
    Militant Moderate

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    • Originally posted by noguru View Post
      Documented and/or recorded instances of observed genetic variation. We are not certain that the forces behind such genetic variation are "random" as you put it. They just appear to be random from some perspectives.
      So you admit that they have no scientific evidence that the changes are due to random mutations plus natural selection"

      Now give us your evidence for "supernatural" intervention?
      I have tentatively rejected this because I believe that creation of lifeforms occurred supernaturally during Creation Week. If you have adequate evidence of supernatural intervention in biology after Creation Week I would be willing to reconsider.

      Did you not claim in another post that protien folding is evidence that micro-evolution cannot become macro-evolution?
      Yes. But this is illustrative only, because I don't really literally believe in micro-evolution. I was using that term only because it quickly conveys the meaning "small changes", and I agree that mutations occur and can cause small changes, genetic diseases for instance.

      But this is not "a small amount of evolution" as the term unfortunately implies.

      Protein folding algorthims, when finally realized, will be able to prove that in biology small changes cannot accumulate to create new organs or new subsystems anymore than small random changes can make roller skates into a racecar (if one assumes that each small change must result in a feasible and better vehicle).

      People typically ignore the key requirement in the presumed evolutionary process of tiny step-by-step changes that the result of each step must not only "work", but actually yield a more successful result from a natural selection standpoint than the last one.
      Random changes are destructive to any carefully crafted piece of work, such as a computer program, a novel or the genome of a lifeform.
      Matt 23:24Ye blind guides, which strain at a gnat, and swallow a camel.

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      • Originally posted by noguru View Post
        Wow that's a mouthful. Say that ten times fast.

        In a red neck accent "I got a cousin who is one a those skeenheads too!"
        Hyuck hyuck! C'mon Cletus! Git 'r done. (I never thought I would actually write that. I feel dirty, so dirty.)
        "Those who have crossed
        With direct eyes, to death's other Kingdom
        Remember us--if at all--not as lost
        Violent souls, but only
        As the hollow men
        The stuffed men." ... T.S. Eliot

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        • Originally posted by bob b View Post
          So you admit that they have no scientific evidence that the changes are due to random mutations plus natural selection"
          I was very clear in what I said. Please don't reformulate what I said to try and make your case look stronger. I will repeat.

          There are reported and documented examples of genetic variation causing major differences in breeding populations in time. To some perspectives the cause of these changes seems to be random. This is usually the perspective from a smaller scope. When viewed from a larger feild of vision, patterns and commonalities begin to appear. This means that "random" is not always a good description of how the changes occurr.
          Militant Moderate

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          • Originally posted by noguru View Post
            Neither am I. In the past I have asked Bob for evidence of a mechanism that would stop many micro-evolutions from becoming a macro-evolution. Protein folding was one response he gave. He did not make it clear how this would prohibit macro-evolution.
            If we omit the hype of the term micro-evolution and use the more accurate "tiny changes" it becomes easier to follow the argument.

            Current evolutionary theory proposes a mechanism to generate new, complex organs through a slow and gradual process of tiny random changes to DNA, where any "trials" that do not result in an improvement (in terms of population increase) are eliminated by natural selection.

            Dawkins inadvertently suggested why this might not work when he used his WEASEL analogy to show us how selection could convert a nonsense sentence into his target METHINKS IT IS LIKE A WEASEL. The process he proposed for computer implementation works fine to achieve his goal.

            The problem is that it has little to do with the proposed mechanism for biological evolution, random mutations plus natural selection.

            First, in biology there is no eventual goal that selection can use to determine what to select and what to reject to achieve the final target sentence, i.e. there is no target sentence. Second, selection cannot "look ahead" so as to preserve partial answers that would lead to the eventual target. In biology partial answers must only only work, they must also be better than the current fully functioning organism.

            So we know that Dawkin's analogy was fatally flawed as far as suggesting anything about the power of "random mutations plus natural selection" to generate new organs in a lifeform that is already fully functioning.

            But wait. The analogy can suggest why small changes cannot work to create something new.

            Try creating a different sentence by making small changes, e.g. letter change, to METHINKS IT IS LIKE A WEASEL. Can you get anything significant by changing a single letter to create a new sentence that also makes sense (works), but not only that, it makes more sense than the current one so natural selection would prefer it.

            Why can't you?
            Last edited by bob b; May 25th, 2007, 03:54 PM.
            Random changes are destructive to any carefully crafted piece of work, such as a computer program, a novel or the genome of a lifeform.
            Matt 23:24Ye blind guides, which strain at a gnat, and swallow a camel.

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            • Originally posted by noguru View Post
              I was very clear in what I said. Please don't reformulate what I said to try and make your case look stronger. I will repeat.

              There are reported and documented examples of genetic variation causing major differences in breeding populations in time. To some perspectives the cause of these changes seems to be random. This is usually the perspective from a smaller scope. When viewed from a larger feild of vision, patterns and commonalities begin to appear. This means that "random" is not always a good description of how the changes occurr.
              As I said there is no scientific evidence, because "seems to be random" is not scientific and the term "change" does not necessarily mean "mutation".

              For example, when parents have a child the resultant DNA of the child is different from either parent, but this is not attributed to the gradual accumulation of tiny random changes.

              When genetic processes were discovered it created consternation in the evolutionary community for a while, because they understood from breeding experiments that although sexual reproduction could create variety it was not the kind of variety that would create new organs, for instance. It was more of an affirmation that the "after their kind" was a wise statement from the past.

              This dilemma was temporarily overcome by the formation of the "new synthesis" or NeoDarwinism" which claimed without scientific evidence that the newly discovered phenomenon of radiation (or other agents) causing mutations in fruit flies was the answer, i.e. random mutations would cause the variation which natural selection would then work with to create new organs and totally new creatures, given enough time.

              Ever since, differences in DNA between populations have been assumed to have been due to random mutations. This is frequently why people count the number of differences and estimate the time required to effect a transformation from one to another by using estimated net mutation rates (if 5 differences take 1 million years then 10 would take 2 million years). Molecular analysis to form "trees" also makes similar assumptions.

              But what if the differences are not all due to random mutations?

              And there is scientific evidence that they are not.

              This was the subject of Lee Spetner's excellent book, Not By Chance.
              Random changes are destructive to any carefully crafted piece of work, such as a computer program, a novel or the genome of a lifeform.
              Matt 23:24Ye blind guides, which strain at a gnat, and swallow a camel.

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              • Of course, evolutionary theory says it's not by chance. Random mutations plus natural selection is not a random process.

                Nevertheless, mutations do indeed appear to be randomly distributed in most cases. This is not the same thing as saying that all locations on a genome are equally likely to have a mutation.
                This message is hidden because ...

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                • Originally posted by The Barbarian View Post
                  Of course, evolutionary theory says it's not by chance. Random mutations plus natural selection is not a random process.
                  So then the claim that evolution has no goal is false then eh?

                  “evolution is not a goal seeking process. It is not looking to make more complex things or even create species.”

                  I don't see how Random mutations + natural selection makes it an non-random process.

                  The mechanisms of evolution—like natural selection and genetic drift—work with the random variation generated by mutation[which is random as well].
                  The voiceless, the wasted...You soaked your hearts in gasoline. Now light it up and burn.

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                  • Ok, bob b, here's the beef. Semantic arguments are done. You want your proof.

                    The Luria-Delbruck fluctuation experiment done in 1943 still illustrates to this day that mutations are undirected and lead to selection. That is, specific mutations are not produced because they are needed by the organism but do result in increased hereditary fitness.

                    The experiment itself is rather simple, which is the beauty of the whole thing. It is often the simplest experiments and simplest observations that lead to large discoveries. This is one of them. In fact, this work was a majory contributor to Salvador Luria and Max Delbruck winning the 1969 Nobel Prize. Their experiment still stands as the gold standard of for demonstrating undirected mutation. Enough with the backpatting.

                    The initial observation was that when T1 virus was added to cultures of E. coli that the culture would turn from cloudy to clear in about a 20-30 minute time frame. This was due to the virus infecting the cells making them burst. However, after a while the culture would become cloudy again. What they found is that the bacteria that recolonized the culture were resistant to the virus, as were their descendents. They formed two hypotheses to explain this observation: (from the 1943 paper)

                    1. Mutation: There is a finite probability for any bacterium to mutate during its life time from "sensitive" to "resistant". Every offspring of such a mutant will be resistant, unless reverse mutation occurs. The term "resistant means here that the bacterium will not be killed if exposed to virus, and the possibility of its interaction with virus is left open.

                    2. Acquired Hereditary Immunity: There is a small finite probability for any bacterium to survive an attack by the virus. Survival of an infection confers immunity not only to the individual but also to its offspring. The probability of survival in the first instance does not run in clones. If we find that a bacterium survives an attack we can not from this information infer that close relatives of it, other than descendants, are likely to survive the attack.

                    What they did to test these hypotheses was grow several parallel cultures. They would then spread these separate cultures onto separate plates that contained virus. The next day they would count the number of colonies on each plate, with each colony representing a single bacterium at the time of plating. If the mutation hypothesis was right, and if these mutations occurred in a random generation before exposure to virus, then the number of resistant colonies should vary wildly between parallel cultures. As an added control, they plated each culture multiple times so that error introduced in the transfer and plating of bacteria could be controlled for. If the acquired hereditary immunity hypothesis was right, then there should be very little variation in the number of resistant clones in each parallel culture.

                    What did they find? In any single culture, the number of colonies on multiple plates was nearly the same. However, there was wide variance between any two cultures. This means that the acquired hereditary immunity hypothesis was wrong and the mutation hypothesis was right. What they had discovered was that mutations conferring virus resistance occurred in a random generation before exposure to virus. The variance seen between cultures was due to the randomness of the mutation. If it occurred in an early generation then there would be many resistant colonies upon exposure to phage. If the mutation occurred in a later generation then there would be relatively few colonies. Because any two colonies were grown independent of each other, there was wide variance between any two cultures.

                    Note: If my explanation is a little hard to follow, you might want to check out the wikipedia page: http://en.wikipedia.org/wiki/Luria-Delbruck_experiment

                    You will also notice that this experiment was done a decade or so before DNA was even discovered. It was later found that T1 phage resistance was due to mutations in the tonB gene, a surface protein responsible for vitamin B12 uptake in E. coli. What was happening is that the T1 virus would bind to the tonB protein which allowed the virus to infect the bacterial cell. Mutations in this gene prevented the virus from ever attaching to the bacteria. This is consistent with the observations made by Luria and Delbruck. They observed that one could separate the bacteria from the phage, evidence that the virus did not attach to the bacteria. Another interesting aspect is that tonB has a high "turnover rate". That is, it does not stay on the surface very long and must be replaced on a constant basis. This means that tonB proteins on the surface would not be transferred to descendents and that all tonB had to be made by each offspring. Luria and Delbruck were lucky that their model had these features because it made it possible to test the two hypotheses.

                    Again, this is not a proof of evolution in general but you seem caught on the topic of natural selection and mutation, so I focused there.
                    Last edited by Neverfox; May 25th, 2007, 06:58 PM. Reason: Additional content

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                    • In case that completely repeatable experiment isn't enough, here's another nail in the coffin.

                      http://www.sciencedaily.com/releases...0224090021.htm
                      Last edited by Neverfox; May 25th, 2007, 07:26 PM. Reason: Spelling

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                      • Originally posted by macguy View Post
                        I don't see how Random mutations + natural selection makes it an non-random process.
                        It's probably better to say that it's a deterministic process rather than non-random. It’s important to understand that when biologists say the mutational process is random, they mean that it is not directed. There is nothing determining definitively that a mutation will occur at a particular nucleotide. But mutations provide the raw material on which natural selection acts. Natural selection is a deterministic process; a beneficial mutation will always reach fixation in an ideal population (i.e., natural selection will cause it to replace all the other alleles), and a deleterious mutation will always be lost (unless it doesn't affect reproductive survival). We have no way of saying for sure whether or not a particular nucleotide will mutate because mutation is a random process – we can only assign a probability that it will mutate.

                        To put it another way, a game of cards or dice uses a random occurance (the roll of the dice of deal of the cards) to determine a non-random outcome (the poker hand or the craps payoff). Thus the game itself is deterministic because certain event outcomes results always in the same end but randomness picks each single event. You don't know what card is coming (random), but you know that a certain card, if it comes, will win you the hand (deterministic).

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                        • Originally posted by bob b View Post
                          For those who continually state "Creationists do not understand evolution", please enlighten us dummies who do not agree that "all life has descended from a single hypothetical primitive protocell" (i.e. the general theory of evolution).

                          What is the best evidence you have that this has occurred?
                          Are you not typing on a computer that your grandfather probably could have never fathomed??? It's not HAS occured, its DOES occur........

                          People put too much emphasise on looks when it comes to evolution. It exist today in everything we do from engineering to religion. Thats all the proof I need right there to say evolution is real. The little leaps and bounds we make today, probably are insignificant to what we will be in 1000 years.
                          I'm not a sinner, or preacher, all I have is slight of hand.

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                          • Originally posted by Neverfox View Post
                            It's probably better to say that it's a deterministic process rather than non-random.
                            Thanks, just wondering what Barbarian was trying to imply.
                            The voiceless, the wasted...You soaked your hearts in gasoline. Now light it up and burn.

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                            • Barbarian observes:
                              Of course, evolutionary theory says it's not by chance. Random mutations plus natural selection is not a random process.

                              So then the claim that evolution has no goal is false then eh?
                              I don't see how you get that. Many non-random processes have no goal.

                              For example, the size distribution of pebbles in many streams is non-random. But there isn't any goal.

                              I don't see how Random mutations + natural selection makes it an non-random process.
                              O.K. Try this.

                              Roll a die a hundred times, and write down the number. But if you roll a prime number, you have to roll again, and get a number larger than three to write that one down.

                              Take a look at the distribution after you're done. It won't be random. And yet you used a random process plus a non-random process to get it.

                              The word random is used to express lack of order, purpose, cause, or predictability in non-scientific parlance. A random process is a repeating process whose outcomes follow no describable deterministic pattern, but follow a probability distribution.
                              Wikipedia



                              The mechanisms of evolution—like natural selection and genetic drift—work with the random variation generated by mutation[which is random as well].
                              See above. You can probably figure it out from here.
                              This message is hidden because ...

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                              • Originally posted by The Barbarian View Post
                                Barbarian observes:
                                Of course, evolutionary theory says it's not by chance. Random mutations plus natural selection is not a random process.
                                Why do you need to repeat yourself? Unless it was like on another page, there would be no need to do so. I agreed with Neverfox, so am I wrong in doing so?

                                Many non-random processes have no goal.
                                I was merely pointing out ONE process to distinguish randomness between non-randomness. It occurs without specific cause, pattern, or purpose.

                                What I want to know if there is such thing as total randomness in the first place...For example, if I flip a coin, the probability of getting heads or tails is equal and the outcome from a toss is unpredictable. It is, however not random because the outcome is determined by a number of factors such as mass of the coin, angle, direction, velocity, power of which the coin was tossed. Other considerations would include the wind resistance, gravity, and how long it flipped in midair. All these can be measured by a quantity of facts. Due to us not knowing all these variables, we cannot predict the outcome but it is still nevertheless not random. Is this what you mean?

                                Roll a die a hundred times, and write down the number.
                                The number you get from the die you mean? I don't have a die by the way. Could you not just use a simpler example such as a coin?


                                But if you roll a prime number, you have to roll again, and get a number larger than three to write that one down.
                                Is this the part that is non-random? Didn't you say that I should only roll the die 100 times? What if my last shot includes a prime number? Would I have to roll the die again? I am not sure about your example but Neverfox explained it rather easily. Thanks for attempting to explain it.
                                The voiceless, the wasted...You soaked your hearts in gasoline. Now light it up and burn.

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