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Evolution: Fact and Theory
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Evolution: Fact and Theory |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Evolution is a fact, not a theory. The theory of evolution, the one proposed by Darwin, is that evolution takes place via natural selection. This theory has been confirmed over and over again by scientists the world over. So, what's the problem? Why is it that so many people can deny this and so many, including myself, take it in stride? 1. I can't imagine it happening. One problem is that our own evolution doesn't incline us to see the vast time differences between our own lives and the speed of evolution. Interestingly, while evolution actually works more slowly than human lives it is, in many cases, much faster than geological time -- sometimes as fast as 100,000 years or even less. 2. Evolution can't explain diversity. Evolutionary theory is designed precisely to explain diversity. The best analogy here is language. It may be hard to fathom, but there is quite a bit of evidence that points to one mother language for all currently extant languages. If true, languages have evolved into an incredible diversity in a very short time. We have new languages springing up in 1500 years or less. 3. How can everything come from one cell? That's an easy one. You come from one cell. Or two if you want to be picky. 4. You can't have half an eye or half a wing. Yes, you can. The chambered Nautilus (It looks kind of like a squid with a shell) has an eye with no lense. What would you call the skin flaps of a flying squirrel? How many of you are wearing glasses right now? Eyes and wings and many, many other things can give you an evolutionary advantage even if they don't work as well as they do now. 5. How can cats evolve into dogs? They don't, evolution is not a linear progression it is best scene as a tree or a bush. Cats and dogs have a common ancestor that was neither a cat nor a dog. The study of this is called cladistics and it's really interesting. 6. What's wrong with saying God made things this way? Nothing. The two aren't in conflict. I've been reading Dawkins, Dennet, and Gould the last couple of months and just wanted to put this up here. Get it off my chest so to speak. I've said some of it before, but the evolution thread seems headed in a very different direction. |
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Essorant Member Elite
since 2002-08-10
Posts 4769Regina, Saskatchewan; Canada |
A question-- Is evolution still evolving or is it a snake that stretched on a path and eventually found its tail and swallowed itself from behind? How do we know? Once evolution swallows itself and ceases to be anything new doesn't it cease to be evolution as well? [This message has been edited by Essorant (12-29-2003 01:56 AM).] |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
Brad, What is commonly referred to as "micro-evolution" is certainly fact. Genetic changes that result in variable traits within species, such as the size of finch beaks, or the color of moth wings. But "macro-evolution" is not fact but theory. It is attributing to random mutation and natural selection the power to produce entirely new systems, and even organisms. This "theory" has even been hailed as the thing that replaces religious ideas about creation. But since it is purported to take place over millions of years it has never been observed, and there are many respectable who doubt the "evidence" is enough to show that it happened that way. Many feel that Darwin's mechanism is not sufficient to explain the diversity of life that we see. I've heard all the arguments about the fossil record. But it is sporadic and convoluted enough to cast considerable doubt. I've also heard many of the suggested ways that complex organ systems arose ... and abiogenesis. But again there is more than a little ambiguity here. Enough actually to warrant the neo-darwin theory more faith-like in nature than purely scientific. You saying it is "fact" is nothing but one more voice saying it is. But it is only a voice saying it is. However probable or improbable we might think it is ... it is a theory. Stephen. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Essorant, It continues. There's a great website and accompanying TV documentary on the Discovery channel about future evolution. Stephan, If you accept micro-evolution, you are accepting macro. They are the same thing. The only difference is our distinction based on our lifetimes. Besides the fact that Gould used the term fact to describe evolution, and theory for the mechanism (natural selection) I specifically used the term in order to group it with other things that people consider as fact. In the above, for example, denying macro-evolution, you're accepting plate tectonics but denying that India slammed into Asia thereby creating the Himilayas. Same idea. How can you accept one extrapolation and not the other? |
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serenity blaze Member Empyrean
since 2000-02-02
Posts 27738 |
Evolution? Sure. I'm in. Put me down for the accelerated version. |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
Brad: quote: and: quote: Don't just beg the question. Of course some say that if micro-evolution (genetic mutations which lead to limited changes in characteristics of species) is true, then macro-evolution (genetic mutations which lead to quantum leaps in design, and entirely new organisms) must be true as well ... But there are more than you might suspect who feel that the actual evidence for Darwin's mechanism being responsible for the general diversity of life, is slim. The intricate and enormous span required for one organ system to become another through mere mutations, is poignantly seen in the recent discoveries of biochemistry. I am no biochemist ... and neither are you. We probably couldn't debate these points. But from what I have read, I have seen that the problem is a real one. Michael Behe describes the situation with a story: " Suppose a 4-foot-wide ditch in your backyard, running to the horizon in both directions, separates your property from that of your neighbor's. If one day you met him in your yard and asked how he got there, you would have no reason to doubt the answer, "I jumped over the ditch". If the ditch were 8 feet wide and he gave the same answer, you would be impressed with his athletic ability. If the ditch were 15 feet wide, you might become suspicious and ask him to jump again while you watched; if he declined, pleading a sprained knee, you would harbor your doubts but wouldn't be certain that he was just telling a tale. If the "ditch" were actually a canyon 100 feet wide, however, you would not entertain for a moment the bald assertion that he jumped across. But supppose your neighbor- a clever man- qualifies his claim. He did not come across in one jump. Rather, he says, in the canyon there were a number of buttes, no more than 10 feet apart from one another; he jumped from one narrowly spaced butte to another to reach your side. Glancing toward the canyon, you tell your neighbor that you see no buttes, just a wide chasm separating your yard from his. He agrees, but explains that it took him years and years to come over. During that time buttes occasionally arose in the chasm, and he progressed as they popped up. After he left a butte it usually eroded pretty quickly and crumbled back into the canyon. Very dubious, but with no easy way to prove him wrong, you change the subject to baseball." and "With the advent of modern biochemistry we are now able to look at the rock bottom level of life. We can now make an informed evaluation of whether the putative small steps required to produce large evolutionary changes can ever get small enough. You will see in this book that the canyons separating everyday life forms have their counterparts in the canyons that separate bilogical systems on a microscopic scale. Like a fractal pattern in mathematics, where a motif is repeated even as you look at smaller and smaller scales, unbridgeable chasms occur even at the tiniest level of life." (Darwin's Black Box) You and I will not be able to argue to any adequate degree, about the probability of these "chasms" being crossed by darwinian steps, since we know little about biochemistry, but at any rate ... there is enough out there written and expressed to show me that Neo-Darwinian Evolution may be an extrapolation, but is certainly not a "fact". Accepting one extrapolation and not the other, could be the difference between the 4-foot ditch and the canyon. Stephen [This message has been edited by Stephanos (12-29-2003 03:22 PM).] |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
Brad, quote: imagination was never supposed to be the issue of what is considered scientific fact. quote: What does that analogy show? That things can "change" or "evolve"? This never was in question. We know that certain organisms, organ systems, and organs, came to be. The question is how? The question is finding the explanatory mechanism. Those who question neo-darwinism question if random mutation and natural selection could have really achieved what is seen. Simply comparing this theory to how languages change, does nothing but suggest that one theory is as certain as another. quote: Nice try, but there is a gargantuan difference between an organism utilizing it's genetic code to build the machine one cell at a time, and one cell without such instructions, attaining them through random processes in time. It's comparable to the difference between a car assembly beginning with one piece of metal on an assembly line, and one piece of metal in a junk yard becoming a car. quote: Actually the problem has been to show how genetic mutations provide consistent functional advantages with each step. With no advantage, mutations disappear. This doesn't seem like such a daunting task, until you get into the biochemistry that explains the formidable distance between a light-sensitive spot, and a seeing eye. quote: But the Cambrian "Explosion" presents a different picture which has been stumbled at ... an inverted bush with many lines converging into fewer. quote: I'll agree, IF he made things this way. But it's still in question in my mind. Stephen. [This message has been edited by Stephanos (12-29-2003 05:55 PM).] |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
quote: Which scientific fact would that be? All Natural Sciences use induction. I live on a volcanic island, the volcano, Mt. Halla, is extinct. Does that mean that it's not a fact that Mt. Halla created this island? quote: I want to keep things straight. Evolution is a fact, you've conceded this here, what you want to dispute is the mechanism, the theory of natural selection. One step at a time, one step at a time.  Now others will read what you say and agree that this is a valid argument against evolution but this is incorrect. Evolution happened, is happening, and will happen. But here's the problem. If you agree that evolution works to some degree but not to say, the speciation level, you've (or Behe) should posit a mechanism that stops evolution. The only argument given so far is irreducible complexity -- and that's not a mechanism, it's the scientific quivalent of, "Gee, I can't imagine how that happened." It doesn't even attempt to answer, "Gee, how did that happen." It's a dead end. quote: How the assembly line got started is a different issue, but we already have the assembly line. It's called DNA. The point of the analogy is to stress that we can already see a tremendous amount of change in a human lifetime. The only difference is familiarity quote: Actually, computer simulations show that it is remarkably easy to create an eye, provided that the program has the same assumptions that our theory of natual selection posits. quote: Not at all, the Cambrian explosion presents a very large tree, the subsequent extinction is a kind of pruning through natural processes. I have no idea what you mean by convergence. Out of time, but I'll try to get to the Behe quotes later. It's a horrible analogy really, confusing human and evolutionary time scales (remember my problem number one?). It's as if we couldn't posit a Bering strait land bridge for humans and others to get to the Americas because it ain't there anymore. And what's all this talk about jumping? It's misleading. Oh, and one more thing, does Behe discuss the odds of all known life of having the same genetic alphabet (about 60 letters) if we weren't all descended from a single ancestor? |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
quote: since when did induction and imagination become synonyms? Induction is still dependent upon the data and likelihood of explanation. In this case, your example is pretty well established. I feel differently about macro-evolution. quote: No ... evolution as an explanation of the diversity of life is not the fact. The diversity of life itself is the fact. "Evolution" is the theory of how it came to be. If by "evolution" you mean differing traits among species arising because of random mutations and natural selection ... I will say "yes" it is fact. But if by "evolution" you mean the origin of all the complexity we see, and the ability for one major system to become another, I disagree. Let us clarify "evolution". Even Behe agrees that Darwin's mechanism works. The question is the scope of it's work. quote: This is just a disagreement about who has the burden of proof. Since we are discussing Macro-evolution, I would say that in order to achieve the ambitious goal of establishing it as "fact" rather than theory, the burden of positive proof would be on the evolutionist at the biochemical level. Otherwise it is "We know it happened, but can't describe it". As to the need for something to "stop" natural selection, why would we need it? Bicycles haven't been shown to travel to the moon, but we don't invent mechanisms that would stop it. The difficulties it would take to get it there apart from a fueled spacecraft, in light of natural law that we already know, are enough to "stop" it. Random mutation and natural selection have not been shown able to produce the complexity at the microbiological level. quote: One little detail you're forgetting ... the assembly line "DNA" and the final product are, for all practical purposes, one and the same. That DNA is part of the organism which orchestrates it's development. The whole question is how that eloborate system came about from one cell that didn't have the DNA (or any thing else) to start with. How can you say the only difference is familiarity?? ... the miracle of complexity was already in place before your birth and consequent growth. quote: I'd be interested in hearing how this intelligence-produced model can really be comparable to unaided natural selection. What are these asumptions? quote: I was more referring to the lack of a trunk. The Cambrian explosion more resembles a tree turned on it's head. If more diverse life followed, instead of pruning, you would say that the subsequent growth was a kind of expansion "through natural processes". This method is so general that it could describe anything at all. The problem the Cambrian period presents us with is that very few real examples of life are preserved beforehand, which can be directly tied to the plethora that sprung up suddenly. The connection is arbitrary and forced ... or so it seems to me. quote: I would encourage you to actually read his book... He is much better at describing the difficulties of evolution at the micro level, than at telling stories. The whole point of the story was not a direct analogy, but to illustrate the difficulty he percieves in his own studies with the general theory. He gets into much greater detail in his descriptions of biochemistry ... and far exceeds my understanding, as well as yours. But it's still fun to read it. And might give you a fresh perspective, to at least counter Dawkins and Gould. Stephen. [This message has been edited by Stephanos (12-30-2003 02:26 AM).] |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
I consider induction a form of imagination but that's neither here nor there -- or will at least wait for another thread. quote: Exactly. Um, how many examples do you need before you put evolution as well-established. Again, the distinction between micro and macro is one that we make because we live for 80 years or so. If we had a lifespan of 5 million years then micro would be in that space of time. quote: Good, because that's not evolution. Current major systems don't become other current major systems, however you want to define them. Fish don't become mammals, mammals don't become fish, they do, however, have a common ancestor. quote: If so, I think my earlier 'shift of burden' makes sense. quote: How much proof do you need? Again, I used fact for a specific reason. You don't throw out Newton because he didn't get the orbit of Mercury right. quote: Exactly. I see nothing in natural law that stops evolution. quote: I think this is the time frame problem. quote: Exactly. The miracle of complexity was already in place for evolution to occur. The orgin of these evolutionary processes is a different question. quote: I think you're confusing random selection with natural selection. You'd have a point if it were completely random, but natural selection is not random. Who set up the program (man or God) is not the issue here. Watching what happens once the program gets going is. quote: I will if you read Dennet, Dawkins, and Gould. Isn't he just basically going to tell me that blood clotting and E. coli motors are irreducibly complex (more on this point later). Also, the problem with the analogy is that it shows an understanding that is, well, wrong. He just isn't talking about it. More later, gotta go. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Recently read a transcript by Behe giving a speech at Temple University. It's an interesting piece as he begins by arguing that amino acid sequencing (this is a way of comparing DNA across species) is irrelevant to how they came to be that way. This is true enough, but the fact that we find remarkable similarities across the spectrum of species still poses an interesting dilemma for those who reject evolution. If evolution were not true, there would be no reason to believe such similarities were possible, and, in fact, that's what was thought some 40 to 50 years ago. Convergent evolution (ie. why dolphins and Ichythisaurs -- hope that's close enough -- look so similar) as the result of natural selection held a much more powerful place in those years. It's still around, of course, but the releatively recent ability -- say about 25 years -- to actually compare DNA structure among wildly disparate species -- has, understandably, swept the microbiology world by storm. The way he puts it, it makes it look like a conspiracy. But by dismissing amino acid sequencing as inadequate for explaining how, he misses the point that the interest in sequencing today is the result of a false belief fifty years ago that such tremendous similarity would not be found, indeed not necessary for evolution to do its work. Doesn't the fact that such similarity is there cry out for an explanation? And wonder of wonders, we have it, a common ancestor. |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
quote: These similarities are no more "remarkable" than the differences ... differences that would in actuality have to be bridged by step by step mutations. Remember that the idea of a designer is also theoretically enough to explain similarities. While Rembrandt may have used the same color paints for many of his works, they remained separate works and did not "evolve" one into another. The similarities you speak of are interesting, and maybe even provocative, but not a conclusive proof for "evolution". More later ... (time squeezed) Stephen. [This message has been edited by Stephanos (12-31-2003 02:59 PM).] |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Understand time squeezed. Creator explains similarity and difference. Creator does not explain mistakes that work. God is simply not very good at what he does. Next step, the human eye mistake. |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
You started off by saying Evolution and theism were completely compatible. Are you going back on that now? What you might call mistakes, I wouldn't ... especially mistakes that work, such as the eye. Stephen. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Not at all. What I want to argue is where God fits in the process. As a programmer of a computer simulation, not as an engineer. If he's an engineer, he's not always doing a very good job. |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
Well Brad, what we are dealing with here is appearances. If Intelligent Design has a problem with apparant "mistakes", then evolution by natural processes has the same problem with apparant intentionality. Anyone would concede that the eye has the appearance (and function) of a machine, of much more complexity than any camera we have suceeded to build. And as far as evolutionary theory is concerned, I still haven't seen how science has demonstrated that something like a "light sensitive spot" can turn into something like a seeing eye, by only small incremental genetic mutations. Especially if each mutation has to provide a functional advantage. There's just too much space between Mars and Earth to get there on a Schwinn. Now anyone can say it happened, or even that they are sure it happened, but it remains a theory until there is proof that such a thing even CAN happen. And variations in the size of finch beaks does not provide such proof. And as to that mistake in the wiring of the Eye I have read about, There's a word for mistakes that work ... "non-mistakes". It reminds me of those who would try to disprove the intentionality of Creation by Quantum Physics. If God is playing dice with the universe, then the dice are infinitely loaded. Stephen. [This message has been edited by Stephanos (01-01-2004 08:05 AM).] |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
What about land and sea turtles? By the way, where is the line between micro and macro in dividing up life? The Schwinn is a splendid example of misdirection. Very much like Behe's analogy. You'll say that cattle, or something very much like cattle, couldn't turn into a dolphin and I'll agree. There aren't any jumps and yet the analogies presented so far all worry about jumping. quote: The mistake here is you're confusing two different types of explanation, I think. I suspect that when you think of the eye you think of the sheer number of cells needed to produce it, but with cameras, you're thinking of breaking it down to its various mechanical parts. Either stay on the molecular level with both and both are complex, stay on the level of parts and they seem just about as simple. quote: The computer simulations are there. It already has been demonstrated that it CAN happen. quote: It seems like your still caught up in the progressive thinking of the nineteenth century. Each mutation does not have to have a functional advantage. In fact, we now think most mutations are quite nuetral. So, we have a species with a spectrum of differences. Some are good for it, some are bad for it, some are nuetral. Statistically, the good ones will win out because that's what good means. Time is definitely being squeezed these days.  |
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Ravenwolfvoyager Member
since 2003-12-25
Posts 326 |
Evolutionists teach that the earth was a boiling hot, molten mass that slowly cooled down over millions of years. The Bible says in Genesis chapter 1 that "In the beginning God created the heaven and the earth ... and the Spirit of God moved upon the face of the waters." So the surface of the earth was covered with water; it could not have been a hot, molten mass. There is scientific evidence to support the Biblical account. Robert Gentry of Knoxville, Tennessee, does amazing research on radio-polonium halos in granite rock. Polonium is a rare element that is radioactive; it breaks down or decays like uranium. But polonium only lasts a few minutes. As it breaks down, it sends off little particles that fly a certain distance. An analogy would be a hand-grenade exploding under water that produces a sphere of fragments in the water that only lasts a fraction of a second before it collapses. Different elements have fragments that fly different distances, each radioactive element has a particular "signature" (how big a circle it can make in the rock as it decays like a more powerful hand grenade would produce a bigger sphere in the water). Radio-active polonium, when it decays in a solid rock, makes a perfect sphere as it decays because all its fragments fly about the same distance from the center. If it decays in solid rock, the circle is preserved. But if it decays in a hot molten rock, the circle disappears. All over the world radio-polonium halos exist in granite, indicating the earth was never a hot, molten mass. |
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berengar Member
since 2004-01-02
Posts 86 |
First, a big hello to everyone out there (I'm a first timer) and a note of appreciation for the work Brad and Stephen have put into this debate. The problem with evolution is that it has not been properly communicated to the masses. Even the scientists with good intentions who write well have occasionally employed turns of speech that muddy things. The distinction between evolution (the ongoing process) and the theory of natural selection is a vital one to make. It's interesting to note that dichotomies shape the tenor of the argument, to look at just a few; micro/macro evolution; given enough time is there no real distinction between micro and macro, or are there barriers of complexity? One for the biochemists, I suspect. evolution/natural selection; Given that 'everyone' accepts evolution (ie: variation, mutation etc), why not natural selection? Well, I think everyone does, but many do not believe that the mechanism sufficiently explains current diversity and complexity of life. There is also 'something else', though what that may be needs to be explained by the naysayers. theory/hypothesis; we could spend forever on this one. If we want to quibbble, we could say Darwinism is not a theory as it cannot (yet) be falsified in the Popperian sense. Indeed, given the time frames it probably never will be. Given that there is no alternative that I've seen which explains biodiversity as well as Darwin, it may boil down to a question of utility. 'limited' agent vs 'inhibiting' agent; Brad and Stephen haven't seemed to resolve this dichotomy yet; how elastic is natural selection? It is paired with how encompassing can the 'reductionist' Darwinian view be? linear progress/bushiness; Given that progress is not an inbuilt quality governing natural selection, the wonder is how improvement happens at all, if most mutations are harmful. I suspect the burden of proof rests on Brad here. Dennett does go some way in conceding some kind of 'progressive' element in the process (unlike Gould, who in my view doesn't address the problem to any great degree), but is this merely figurative and therefore invalid? Can we only describe natural selection figuratively given the timescales and complexity of the actual development? Creationism/evolution; manifestly a false dichotomy. There is too much of the 'I'm a Christian therefore I don't believe in evolution...' silliness floating around the cybersphere (not here, of course). I'm wholly with Brad on this; even if you accept Darwin's theory you do not preclude God (the ethical parameters of an interventionist God are another story), as it says nothing about how life was created. Dennett has made a nice try using Darwinism to explain how life got started (Darwin's Dangerous Idea, highly reccommended) but the Jury's still out on that one. The problem with computational designs simulating natural selection over time is that there is a designer. Similarly, natural selection (whether you view it as a sufficient explanation for current diversity or otherwise) follows it's own self-consistent mechanism. That may be an interesting topic to discuss; how did the laws that govern the process come to be? Are they necessarily 'designed'? I hope some of this helps. It's not as long or as profound as I would like, but time reigns. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Ravenwolfvoyager, That has nothing to do with evolution. What is evolution? Darwinian Evolution: 1)Within organisms, there is a large amount of diversity. 2)This diversity is explained by small changes accumulating over time. 3)The mechanism that shapes these changes is natural selection. Questions of earth origin and even life origin are interesting, but don't touch evolution. |
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Krawdad Member Elite
since 2001-01-03
Posts 2597 |
Okay, I gave this discussion a fair read. And I'm afraid that I gave it more time than it deserved. There is too much confusion of and misapplication of terms and concepts (which are not defined). I see nonsense throughout. e.g. What in the world is "the miracle of complexity"? (One miracle is as good as the next, I suppose?) or, "Within organisms, there is a large amount of diversity'? What in the world does that mean? And what does that have to do with evolution? I'll try to make one thing clear that is so often confused or misunderstood, as it appears to be here, and let it go at that. Natural selection is about reproductive success. That is all that it is about. If organisms live long enough to reproduce, and leave live offspring behind, then they have succeeded (or, if you will, have been selected). Genetic information follows this success, and should not be said to lead it. It also follows that a mutation that abrogates this sequence cannot succeed. There are, of course, other factors not a part of natural selection, that lead to failure. My time allotment has expired . . . |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Unfortunately, Krawdad, you haven't done much to clear it up. quote: I don't know why this is difficult to understand. I was trying to avoid the term species, genetic cluster groups, and the entire tree (bush?) of life simply because the statement applies to all three. Anyway, you split it up, there is diversity. quote: It is important for evolution because it is Darwin's assumption. Darwin does not discuss the origin of life in "The Origin of Species" and, in fact, doesn't describe the origin of species in "The Origin of Species". He starts in the middle -- and remember, he didn't know anything about genetics. quote: Um, who misunderstood that? quote: It is unfortunate that you chose to use the word follow here (and lead) for these are the words that I'm trying to avoid. Diversity happens. Natural selection actually slows down the process of diversification and shapes organisms cumulatively over successive generations (hmmm, maybe I didn't make the generational thing clear enough?). But the standing assumption is still that diversity is already present. Because diversity is already present, the mechanism of natural selection can do its work (Some animals will live and reproduce, some won't). There is, of course, no leading or following here. Reproductive success just is genetic heritability. |
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jbouder Member Elite
since 1999-09-18
Posts 2534Whole Sort Of Genl Mish Mash |
Brad: I agree with you that evolution is not a scientific theory, but not that evolution, broadly speaking, is a fact. Evolution is more accurately a historical theory involving an interpretation of various facts, including intra-specie evolution and the apparent progression in the complexity of organisms in the fossil record. Until we actually observe an organism evolve into a distinct specie, macro-evolution will retain its uncertainty. Absent the intervention of a Creator, the historical theory of evolution may be the best explanation we have now, but if we allow that a Creator could have used evolution as His chosen vehicle, we must also be open to the possibility that He created everything more or less the way it is. Or perhaps mice contracted with an alien race in order to determine the question that rounds out the answer to life, the universe, and everything. At any rate, the pragmatist in me can think of better ways to apply our growing knowledge of the genetic biology than trying to unravel the origin of species. Jim |
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Ron
Administrator
Member Rara Avis
since 1999-05-19
Posts 8669Michigan, US |
quote: Shame on you, Jim. The pragmatic value of knowledge is rarely known in advance. |
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jbouder Member Elite
since 1999-09-18
Posts 2534Whole Sort Of Genl Mish Mash |
Ron: lol. But I shouldn't have to walk around the block to grab a coffee next door either. Jim |
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berengar Member
since 2004-01-02
Posts 86 |
Two things I'd like to see discussed on this forum; 1) If natural selection follows its own self-consistent algorithm, whither comes the design parameters?? 2) If natural selection has many problematic features, is there any other scientific theory out there that can explain biodiversity just as well, or better? Have a nice day, everyone. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Jim said: quote: We have observed evolution happening in our lifetimes. Again, the only distinction between micro and macro-evolution is that of our observing times. quote: What remains uncertain is the actual, individual 'just-so' stories of many current species. I also am pretty confident that we've gotten some of these wrong. But I fail to see, how evolutionary processes differ in fact in any way from geological of cosmological processes. quote: It is a logical possibility, yes. But nothing points in that direction. If you start from that assumption, you have to explain anomaly after anomaly. If you start from an evolutionary perspective, they start to make sense. quote: And so, perhaps they did. Again, a logical possibility but one that doesn't defeat evolutionary processes. quote: And yet the evidence for evolution, with the reintroduction of Mendelian genetics, the discovery of homologs in the genome, the use of the same genetic alphabet in all species today, all of these point to evolution. The reason why I want to push evolution as a fact is simply that it does happen. Even in our own lifetimes, we've seen significant changes in successive generations to warrant the idea. No one disagrees that we've, in fact, directed evolution in some species for several thousand years. We've changed species and made some go extinct. Does the fact that we've directed, consciously or unconsciously, evolution somehow, negate the fact of evolution? I don't see how. Again, evolution is a fact, natural selection is the theory of a non-random force that shapes evolution. Which brings me to berengar's second point: quote: I don't think so, but it strikes me that many don't want it to be explained. As it comes to the burden of proof, again I see no mechanism to differentiate between micro and macro-evolution, it's the same thing. If you want to make a distinction there, I really think you have to do a little better than, "We can't see the kind of change happening in the world today in our lifetimes, how could it happen in a million, ten million, or a hundred million years?" On the other hand, is part of the problem the difficulty in understanding 'jumping' evolution and accumulated evolution? Is that where the incredulity comes into play? quote: The laws of physics, the diverse spectrum of natural organisms, and number crunching. Where do these come from, I don't know. |
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Local Rebel Member Ascendant
since 1999-12-21
Posts 5767Southern Abstentia |
Um, I think you would mean to ask where the laws of physics -- for this universe -- came from...? Heisenberg... of course Which is really just a function of the topic.. or the other way around. Good thread -- haven't been ignoring it -- nobody seems to need any help raising the issues though. |
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Stephanos
since 2000-07-31
Posts 3618Statesboro, GA, USA |
quote: Brad, you're doing it again ... minimizing the difference between a finch's beak changing size, and a light sensitive spot becoming a seeing eye. It's explaining the crossing of a canyon, by illustrating the hopping over a mud puddle ... conveniently sidestepping the benefit of an explanatory bridge. I'm not saying it's impossible ... I'm saying that from a biochemical standpoint, it is astronomically unlikely, and therefore quite far from escaping it's theoretical status. quote: Nothing points in that direction ... of design? You are in disgreement with a multitude who have "inferred" design. Don't complain too much about the invalidity of inference, if it is after all acceptable enough to make macro-evolution credible without the scientific rigors which provide unambiguous models. quote: If you start from the assuption of evolution, you have to explain apparant intentionality and artifact after artifact. If you start from a design perspective, they start to make sense. quote: No one denies that change happens. The question is what can Darwin's mechanism do? Yes you are right the idea is warranted ... but not the fact. quote: Are you suggesting that genetic manipulation by intelligent humans provides proof for evolution? That's a quite different situation than random mutation and natural selection. We could just as easily use such examples as proof for design. While you keep saying "evolution" is the fact ... I would still say you are merely restating the fact of change in biology ... without knowing to what degree, or from what sources exactly. Biodiversity itself is the absolute fact or condition of the world. Neo-Darwinian evolution is still absolutely theory. Stephen. |
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berengar Member
since 2004-01-02
Posts 86 |
Stephen, I have enjoyed reading your replies to Brad. What I note is that Brad offers a scientifc theory that is open to critiques, whereas I am mystified over what your own theory is. May I ask for your explanation of current biodiversity? Have a nice day. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
quote: Well, you're doing it again too. What I'm comparing is the slight difference in a finch's beak size to a slightly more sensitive 'light spot'. Over time, say two or three million years, these processes can turn into the beak of a giant moa or the eye of a fish. Here's a quick summary of the intermediate stages for a fish eye: http://www.cs.colorado.edu/~lindsay/creation/eye_stages.html quote: Randomly, you are correct, but the theory of natural selection is not random. Again, the metaphor of jumping and of canyons, but on evolutionary scales canyons weren't there that are there now. Again, the confusion of time scales. quote: I mean that we haven't found any evidence to indicate a designer, a design signature if you will. Believe it or not, design companies have started putting their own design signatures into their genetic codes. Why not this designer? Have we found a quote from the Bible, say in Hebrew, in any naturally floating DNA? Not yet. quote: We see intentionality because we are intentional creatures. Doesn't that make sense? But we have plenty of examples of elegant 'design' resulting from a few well placed instructions. Migrating birds, for example, don't intentionally make that beautiful 'V' shape, they follow a few simple rules that results in a 'V' shape. During the summer, something like five to ten thousand birds (I think they were swallows) perched on the telephone and electrical wires just outside my house, they were beautifully symmetrical. Design? Nah, they had an instinctive space mechanism that didn't allow them to get too close to each other (and indeed they often fought each other over this space). The appearance of design was just that, appearance. quote: Hmmm, maybe we can make some progress here. I said Darwin's mechanism was a theory for the fact of evolution. Now, I've attempted to defend both, but in the back of my head, this distinction has always been clear. Behe himself says, I think the term he uses is 'fairly convinced,' of common descent. That is, he doesn't dispute that evolution happened, but that the mechanism of natural selection doesn't cover everything. My point is that, even if true, you still don't throw out the baby with the bathwater (as many on your side of this debate seem desperately at pains to do -- not you personally of course). What seems to happen, then, is the eternal search for the smoking gun, the one knock down argument that proves evolution wrong. But there is no smoking gun, there just isn't one argument that will dislodge it. Take the genetic signature, for example. Let's say you find it in one place, what you then have to do is find it everywhere. This will take time, at least as much time as it has to amass the evidence for evolution. Why? I said: quote: And you responded: quote: But this is a misinterpretation. What I meant was that directed evolution does not in and of itself disprove evolution through natural selection. We already have evidence for both. We're the directors. quote: Evolution is the process of small changes becoming big changes over time. That's a fact. The Darwinian theory of evolution is that this is accomplished through natural selection. There's a huge amount of evidence to support this theory. Is it complete? Of course not, we have a lot more work to do. If evolution is not all encompassing, if natural selection doesn't fit every situation (and, as I've said, we already know it doesn't), I suspect that it will be those who do the work in evolution that will show this. Let's let them do the work and see what happens. Now, I want to end with a return to berengar's point about Design Theory. If we concede a designer, shouldn't we then ask how he or she did it? |
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Local Rebel Member Ascendant
since 1999-12-21
Posts 5767Southern Abstentia |
 Thought the previous discussions could use some review in light of the recent alley thread... |
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