The Origin of Novelty

Darwin actually did a good job of discussing the evidence as it concerns the eye (at least in molluscs):

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In looking for the gradations by which an organ in any species has been perfected, we ought to look exclusively to its lineal ancestors; but this is scarcely ever possible, and we are forced in each case to look to species of the same group, that is to the collateral descendants from the same original parent-form, in order to see what gradations are possible, and for the chance of some gradations having been transmitted from the earlier stages of descent, in an unaltered or little altered condition. Amongst existing Vertebrata, we find but a small amount of gradation in the structure of the eye, and from fossil species we can learn nothing on this head. In this great class we should probably have to descend far beneath the lowest known fossiliferous stratum to discover the earlier stages, by which the eye has been perfected.

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In the Articulata we can commence a series with an optic nerve merely coated with pigment, and without any other mechanism; and from this low stage, numerous gradations of structure, branching off in two fundamentally different lines, can be shown to exist, until we reach a moderately high stage of perfection. In certain crustaceans, for instance, there is a double cornea, the inner one divided into facets, within each of which there is a lens shaped swelling. In other crustaceans the transparent cones which are coated by pigment, and which properly act only by excluding lateral pencils of light, are convex at their upper ends and must act by convergence; and at their lower ends there seems to be an imperfect vitreous substance. With these facts, here far too briefly and imperfectly given, which show that there is much graduated diversity in the eyes of living crustaceans, and bearing in mind how small the number of living animals is in proportion to those which have become extinct, I can see no very great difficulty (not more than in the case of many other structures) in believing that natural selection has converted the simple apparatus of an optic nerve merely coated with pigment and invested by transparent membrane, into an optical instrument as perfect as is possessed by any member of the great Articulate class.

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Charles Darwin, Origin of Species, Chapter 6
The Origin of Species: Chapter 6

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This hits on two parts. First, a transitional fossil is not necessarily ancestral. This was made plain by Darwin from the very start. A transitional is a fossil or living species that show "gradations having been transmitted from the earlier stages of descent, in an unaltered or little altered condition".And of course we can point to much simpler eyes, such as those found in basal urochordates and planaria.

I think subbie gave you evidence in post #7 that might help in this conversation:"The website for Encyclopedia Britannica has a very nice graphic showing various stages in the process, including an example of a currently living organism for each stage." (emphasis mine)We see the transitional stages.

That was already done in a previous post [edit: a previous thread actually]. We used melanism in pocket mice because we could trace the adaptation to specific mutations in a specific gene:"We conducted association studies by using markers in candidate pigmentation genes and discovered four mutations in the melanocortin-1-receptor gene, Mc1r, that seem to be responsible for adaptive melanism in one population of lava-dwelling pocket mice."
Just a moment...So we can point to specific mutations that give rise to novel phenotypes.Edited by Taq, : No reason given.

Dog breeds adapted to water are a good example. For example, Newfies have much more webbing between their toes than wolves do. This is because this trait was selected for by breeders who were looking for a dog that is a strong swimmer (Newfies helped with gathering nets and saving those who fell overboard).We also understand the developmental pathways that are involved. We all start with webbed phalanges. During development a process called apoptosis removes the skin between them. For webbed feet, all you need is a mutation that turns off apoptosis during this period of development.

What makes it plausible is that each stage offers an advantage over the previous stage. A depressed pit offers crude directionality. Pinching the opening to a pin point can produce a focused image just like a pinhole camera. Covering the opening protects the sensitive retina. Manipulating that covering offers much better focusing, more light, and a better image.

It would appear to me that Bolderdash wants to see these changes on such a fine scale that they will cease to be novel structures as they will be slight modifications of what is already there (just as your fins to legs example demonstrates).

Perhaps a better example would be the evolution of the mammalian middle ear where bones change function in a stepwise manner.Reptiles have one middle ear bone and three lower jaw bones. Mammals have three middle ear bones and one lower jaw bone. So what happened? When mammals evolved from reptiles two of those jaw bones became middle ear bones (in an irreducibly complex system, nonetheless). There was even an intermediate step where there was a double hinged jaw joint.29+ Evidences for Macroevolution: Part 1

I think this is a good example of the disconnect between scientists and the general public. How a scientist views a problem is quite different from how you may view that same problem. I can understand why people think scientists are jumping the gun when there are still so many basic structures that do not have a well understood evolutionary history. Hopefully I can explain where scientists are coming from.Scientists have to be pragmatists and use the evidence they have in front of them. This set of evidence is always going to be imperfect, and there may be evolutionary pathways that may never be known, ever. However, theories are meant to be an explanatory framework for the facts we DO have, and in that sense the theory works amazingly well. Time and again we see a nested hierarchy. We see lineage specific adapations. We see the fingerprints of evolution wherever we look in biology. Time and again the evidence fits what the theory of evolution predicts it should be. The theory explains what we know in biology. That is why it is accepted by over 99.9% of degreed biologists worldwide. Perhaps you can tell us why you think that mutations and selection are incapable of producing these changes, or why you think the case has not been made.If we were to compare chimps and humans, would you agree that the reason we look different from chimps is that the DNA sequence of our genome is different? If so, can you point to any those differences that the observed and known processes of mutation could not produce? Or we can say, "I don't know". Some things will always be a mystery unless we invent time travel. That is exactly what Lenski observed in his E. coli experiment:E. coli long-term evolution experiment - WikipediaThey found that neutral mutations in earlier generations made possible beneficial mutations in the future. This very process has been observed in the lab. Mutations are still occuring. You were born with 50 to 100 mutations not found in either of your parents, and your children will have about the same number of mutations specific to them along with half of the mutations specific to you. This process never stops.Also, evolution doesn't start from scratch. It starts with already existing species and modifies already existing genomes.

No, you will be able to tell which direction the sunlight is coming, and also which direction shadows are coming from. Are you saying that you have never heard of a mutation being passed on? Perhaps you want to think about that one for a second?

It is a proposed pathway by which there is a selectable advantage at each step showing that eye development is attainable by selection. Also, there are living species with each type of eye. For example, the planaria has a simple depressed eye spot. Until you show us how to measure genetic information that is impossible to say. Then evolution does not need to produce new information in order to evolve novel functions.

It doesn't need to be troublesome at all. You could simply define new information as a new DNA sequence produced by a mutation. It could be a very simple thing to measure and understand.The problem in these discussions is that creationists define new information as "what evolution can not produce". Each creationist has different ideas of what evolution can not produce, so we get an almost endless string of vague definitions. Even worse, they usually have nothing at all to do with actual biology or genetics. In fact, creationists strain the definition of "new information" so severely that by the end of a discussion you come to the conclusion that evolution does not need to produce the creationist vision of "new information" in order for evolution to produce the biodiversity we see today."New information" is really just a placeholder for "I don't believe you" in creationist talk.Edited by Taq, : No reason given.

Evolution is extremely useful in explaining the development of life's features. What you are asking for is specific historical events which we may never have enough evidence to reconstruct even if we understand the mechanisms that were involved.Let's use gravity as an analogy. I say that gravity is a very good explanation for why planets orbit their star. You tell me that gravity is not a good explanation. Why? Because I can not show that planets in the Andromeda galaxy are moving about their star in a way consistent with gravity. I point out that we simply can not see those planets because they are too distant, but this does not stop you from using this absence of evidence to try and refute gravity.We will never know the history of every feature found in life. Never. What we can do is test the theory of evolution using the evidence we have found, just as we test the theory of gravity against the planets we can see. Time and again, the evidence we find fits the predicts made by the theory of evolution. That is why the theory is accepted by biologists, because IT WORKS, just as the theory of gravity works. We have mountains of evidence supporting evolution.29+ Evidences for Macroevolution: The Scientific Case for Common Descent

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There is nothing compelling at all about a theory that says you can get step by step development of highly complex and precise systems through a random series of mistakes, when we NEVER see the side effects of those random, purposeless series of mistakes.

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We do see the result of those mutations. The differences between us and chimps is a perfect example. Evidence please. We are not the ones ignoring the evidence we do have. That would be you.Edited by Taq, : No reason given.Edited by Admin, : Fix quote.

No one has yet shown that IC systems can not evolve. That is what is being referenced. Just because Michael Behe can blithely say, well, you see, a mousetrap missing a part stops functioning as a mousetrap, you seem to think that this is actually making a point about evolution. I can point to bones that once functioned as jaw bones but now function as ear bones. This is seen in the transitional fossils between reptiles and mammals. We can actually observe the evolution of an IC system in the mammalian middle ear.29+ Evidences for Macroevolution: Part 1

This is an argument from incredulity which is a logical fallacy. Claiming something is preposterous is a long ways away from actually demonstrating that something is impossible.Even more, the pattern of shared and derived sequences between species exactly matches the pattern we would expect from random mutations and selection (along with other mechanisms such as genetic drift). We have the evidence that these mechanisms were active in the past.Do you agree that the differences between humans and chimps is due to a difference in DNA sequence? Yes or no? Mutations in just one gene can change the development pattern that involves all of those genes.

I have cited the evolution of the complex mammalian middle ear where jaw bones evolve new function.I have cited pocket mice where specific mutations gave rise to a novel fur color. Not only that, but DIFFERENT mutations gave rise to the same phenotype in separate populations of pocket mice demonstrating the random nature of mutations.I have also cited the DNA differences between humans and chimps.Perhaps you can explain why none of these are valid topics for this conversation?