The Edge of Evolution: The Search for the Limits of Darwinism

EdgeOfEvolutionSuggested by Brad Nelson • Although Darwin’s theory can explain marginal changes, random mutation and natural selection explain very little of the basic machinery of life. The “edge” of evolution is a line that defines the border between random and nonrandom mutations. Behe argues that most mutations have been nonrandom.
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18 Responses to The Edge of Evolution: The Search for the Limits of Darwinism

  1. Brad Nelson Brad Nelson says:

    In my continuing education of the obscure and inexplicable, I purchased this book last night. It is the follow-up to Behe’s “Darwin’s Black Box.”

    I’m 20% into it, and not quite into the gist of it. Behe is building his case. He affirms the common descent of all life via delving into the similarity of DNA sequences from various species, including anomalies in that DNA. Yes, according to him, we share a common ancestor with the chimpanzees.

    Most of the early part of the book is a look at what random genetic mutation can be expected to do. The main driver for evolution is said to be like an arm’s race — one species (the lion) driving the gazelle to run faster and jump higher. And when the gazelle does so, this puts further pressure on the lion to up the ante.

    Behe makes the case that “arm’s race” is the wrong analogy. Rather, it is “trench warfare.” Instead of random mutations driving the building of new and robust structures, instead it is a case of degrading existing structures — of “burning bridges” in order to evade a pathogen, for example. And Behe looks into one of the greatest battles known to science, that between mankind and the malaria bug.

    This, he says, is a useful case in order to show exactly what random mutations can do for you. In the case of the trench warfare between humans and malaria, it has caused the human body to try to immunize itself from the bug by degrading its hemoglobin. A slightly weaker hemoglobin will cause the entire protein to “gel” when invaded by malaria, thus ruining the home for the invader (in the case of the sickle cell mutation). Or, in the case of other mutations, it will make the hemoglobin weaker so that any invasion by malaria will cause the spleen to weed out these cells as faulty (although biologist aren’t quite sure exactly how this works).

    The sickle cell defect (which accidentally gives one immunity from malaria) is caused by changing just one amino acid on the hemoglobin protein. And after thousands of years, the malaria bug has not evolved a response. But it did, within a matter of decades, evolve a response to quinine and other similar drugs. According to Behe, the reason it took so long was that not just one random mutation was needed but two. And the more mutations that need to appear at once, the longer it takes to achieve. Malaria can achieve these long odds because of its huge population size and the number of humans who are typically infected with the bug at any one time. But Behe says that any mutation, even for these bugs, that requires three mutations to appear at the same time in order to accomplish some function is all but impossible. Even so, malaria’s response to quinine was to degrade its own digestive system (which somehow keeps it safe from quinine), for when quinine isn’t present in the general environment, the strains of malaria without this mutation do better and predominate, thus showing that this was indeed a case of “trench warfare,” of a degradation of function.

    I have yet to range into the part of the book where he talks of “non-random” mutations and how they supposedly have been the instrument of construction and change. I’ll report back. But so far the book is highly readable and gives you a good background on some of the biological and genetic issues.

    • Timothy Lane says:

      Yes, that’s a very interesting book, and in fact one of my sources for my own comments on the subject (you may recall my mentioning of a human mutation that causes someone with 2 sickle-cell anemia genes to escape the disease, but also lose the immunity that doesn’t matter in many places anymore, which has appeared in New York).

      One thing I will point out as a flaw in the book: Behe looks at the difficulty of going from one genus to another, using a tall hill as an analogy. It’s a good analogy, at least today, but not so applicable in the Cambrian period (when the hills would be much lower).

      • Brad Nelson Brad Nelson says:

        Here’s an article about a full-fledged fish being found in the Cambrian explosion, and the earlier part of it, to boot. Looks like Darwin’s got some ‘splanin to do.

        I suspect we will find some mechanism quite outside of random mutation. The difficulty for any other explanation (which is why they are inherently teleological) is that the creature (or someone) must look forward toward building something useful. Unless, of course, there is another way to do gradualism other than via random genetic mutations — a process that I think Behe is showing (and is going to show) is just not going to get it done in the time allotted.

        Also, Behe makes a singularly interesting point that natural selection is not going to be forward looking enough to get you to the Big Hill way over the horizon (which represents some fancy new system). He notes that if there is any natural gravity, so to speak, toward selecting for “better” traits, then natural selection will just as easily drive you to the top of some small mound that is close by (to a longer beak, for instance)…from which the larger hill is inaccessible. You’re already at the top of something. You’re getting ever-specialized but are not driving toward, say, something as complex as the human immune system.

        • Timothy Lane says:

          Yes. As I said, this would be less of a problem 500 million years ago, when the hills were smaller, but it explains why the only examples of natural evolution today (aside from the likes of Luther Burbank, which even Richard Dawkins may realize didn’t engage in Darwinian processes) are the sort of micro-evolution that even most creationists accept. This is why the Darwinists have to smear the creationists by lying about their beliefs.

  2. Brad Nelson Brad Nelson says:

    I can see why Behe is so hated by the Church of Charles crowd. He doesn’t deny evolution. He doesn’t even deny the common ancestry of all life. Nor does he deny natural selection and gradual change via random mutations. He’s quite reasonable in his explanations.

    What he’s doing in this book is spelling out the limits of the Neo-Darwinian theory — a theory that I would say is more of a matter of a type of secular faith then it is of reason and evidence.

    Roughly speaking, the limits of gradual natural selection via random mutation is either more than two mutations at one time occurring or more than several simple stepwise mutations that do simple (usually destructive) things. In one of the best cases known of gradualism, he cites a certain kind of antarctic fish that evolved the ability to not freeze solid. The repeated duplication of a gene (a common occurrence, something that doesn’t generally create any new information) caused the coding for a protein that stopped the crystallization of ice inside the fish’s body. If you can’t form ice crystals, no matter how cold the water is, you won’t freeze.

    Behe likened this type of mutation is not the building of any new structure but of garbage piling up behind a damn. This flotsam and jetsam of sticks, leaves, and other detritus would be recognized as distinctly different than the Hoover dam, for instance, even if both held back water. Both can dam a river, but one is clearly a more complex structure while the other is just junk that accumulates that accidentally has a useful function.

    In making his case, Behe is citing the most recent research in biology. Apparently science has learned a lot — including about the subject of his earlier book, “Darwin’s Black Box.” In that book, Behe cites irreducible complexity as a barrier to standard Darwinian theory. And he cites the cilia and flagellum as examples of irreducible complexity.

    Behe goes into more detail on both. And science has learned more about both. And what at first look seemed “irreducibly complex” now looks doubly if not triply so. Following descriptions on the ability of some stepwise mutations via natural selection to do something (no matter how simple), his message hits home when delving into the intricacies of the cilia and flagellum. These structures beg for an explanation other than “dumb’ natural selection via stepwise and gradual mutation. You don’t have to be a bible-thumping snake-handling theocrat to think so.

    But you do have to be a Origin-of-Species-thumping Darwincrat to dismiss all the problems of Neo-Darwinism to a mere religious impulse. There may yet be some naturalistic solution to the making of these highly complex structures. Behe insists that “non-random” mutation is behind the building of them. I’ll see what kind of case he can make for that when we get to that point. And I don’t wonder if such an explanation will leave me with the same sense of dissatisfaction of Stephen Meyer’s books when, standard Darwinian theory being totally demolished, the answer was then a carte blanche “intelligent design.” Whatever the truth of the matter, saying “God did it” doesn’t leave much else left to say.

    But I shall continue to report back as I read this book. Suffice it to say, I think Behe’s case against the power of Neo-Darwinism beyond the mere margins is a good one. Whether we are then left with “non-random mutation” (whatever that means) remains to be seen. He does emphasize an implication of natural selection that others had noted at the time.

    One should note that Richard Dawkins’ “Mount Probable” was an analogy for what stepwise natural selection via random mutation could supposedly do. You didn’t have to climb to the top of the mountain in one leap. You could get there in steps. But the problem with this notion, as Behe points out, is that there is not just one mountain as in the Dawkins analogy. That one big mountain would represent just one trait — say, the giraffe’s neck getting longer or the cheetah running faster. But there are many ways at one time for an animal to improve. There are many mountains, mounds, and low hills. And once one has climbed up one, it may preclude ever climbing down again (at least according to Darwinian theory).

    For instance, Behe notes the analogy of trying to build a 20 story building. One may start with a wood-framed building that one can then extend to several stories. But at some point, you will reach the limit on how high you can build with wood. But once you have, you can’t simply demolish what you’ve done in order to start again with steel beams. Darwinism forbids a movement to reduction of function.

    So the point is, it may indeed be theoretically possible to step your way up some hill. But you have to do so by picking your way through all the other hills and basically ignoring them. Again, we run into a situation, according to Behe, where something may be theoretically possible but the odds are extremely stacked against it. Behe notes how ingrained storytelling is to the Darwinian mode of thought. But the details underneath (particularly at the molecular level) are what matter.

    • Timothy Lane says:

      I think you do a bit of misphrasing there. One can certainly demolish a building to rebuild it with new materials capable of supporting a much larger structure. But that would be equivalent to some sort of creator (or intelligent designer), not Darwinian evolution. The Darwinian equivalent would involve gradually converting a wooden structure to a modern skyscraper without at any point making the building less functional than it already is.

      • Brad Nelson Brad Nelson says:

        Perhaps I didn’t make it clear that I was paraphrasing Neo-Darwinian evolutionary theory. Did you read the ending sentence in that paragraph, “Darwinism forbids a movement to reduction of function”?

  3. Brad Nelson Brad Nelson says:

    Here’s an interesting quote from the book, typical of the kind that take the assumptions of Neo-Darwinism head-on:

    Time has always figured prominently in Darwinian explanations . Although few changes can be noticed in our own age, Darwinists say, over vast stretches of geological time imperceptible modifications of life can add up to profound ones. It’s no wonder that we don’t see much coherent variation going on in the biology of our everyday world— evolutionary processes are so slow that a human lifetime is like a moment. The work on malaria and HIV upon which I base much of the argument for the edge of evolution has mostly been done in just the past fifty years. So how can it tell us anything reliable about what could happen over millions or even billions of years? Time is actually not the chief factor in evolution— population numbers are. In calculating how quickly a beneficial mutation might appear, evolutionary biologists multiply the mutation rate by the population size. Since for many kinds of organisms the mutation rate is pretty similar, the waiting time for the appearance of helpful mutations depends mostly on numbers of organisms: The bigger the population or the faster the reproduction cycle, the more quickly a particular mutation will show up. The numbers of malaria cells and HIV in just the past fifty years have probably greatly surpassed the number of mammals that have lived on the earth in the past several hundred million years. So the evolutionary behavior of the pathogens in even such a short time as a half century gives us a clear indication of what can happen with larger organisms over enormous time spans. The fact that no new cellular protein-protein interactions were fashioned, that mutations were incoherent, that changes in only a few genes were able to help, and that those changes were only relatively (not absolutely) beneficial— all that gives us strong reason to expect the same for larger organisms over longer times.

    “God of the Gaps” arguments are often thrown into the faces of the religious, and often rightfully so. But evolutionary theory is full of “Darwin of the Gaps” arguments or rationalizations. Whatever material difficulties occur in regards to evidential and logical support for the theory, Darwinists can always fall back on, “Well, these things are always hard to see in the present. But if you add up what can happen over million of years, its inevitable.”

    I think Behe does a great job of exploiting this weakness. As he notes, there has been a universe of evolution (at least regarding mutations and survival-of-the-fittest scenarios) in the life cycle of the HIV virus and the Malaria parasite since science began studying them. And in all that time not one new protein combination (the base and real level of new structures) has emerged. Notta. Zip. Zilch. And as Behe notes in particular about the Malaria protozoa, it would be enormously beneficial to this parasite if it could evolve the ability to live in cooler climates. But it hasn’t. Why not? That one fish I mentioned earlier certainly did find a way to live in arctic waters via a rather dumb sequence of mutations (what Behe referred to as “garbage piling up”). This would suggest that real structural changes are beyond mere “garbage” or “dumb” random mutations and natural selection.

  4. Brad Nelson Brad Nelson says:

    Here’s another excerpt that is well worth presenting and reading through:

    Still, are the numbers we’ve examined enough? A hundred billion billion (1020) malarial cells and HIV viruses is certainly a lot, but it’s minuscule compared to the number of microorganisms that have lived on the earth since it first formed. Workers at the University of Georgia estimate that 1030 single-celled organisms are produced every year; over the billion-year-plus history of the earth, the total number of cells that have existed may be close to 1040. Looked at another way, for each malarial cell in the past fifty years there have been about 1020 other microorganisms throughout history. Can we extrapolate from malaria and HIV to all of bacteria? To all of life?

    Sure. We do of course have to be cautious and keep in mind that we are indeed extrapolating, but science routinely extrapolates from what we see happening now to what happened in the past. The same laws of physics that work here and now are used to estimate broadly how the universe developed over billions of years. So we can also use current biology to infer generally what happened over the course of life on earth. Since we see no new protein-protein interactions developing in 20 cells, we can be reasonably confident that, at the least, no new cellular systems needing two new protein-protein interactions would develop in 40 cells—in the entire history of life, as illustrated in Figure 7.4. The principle we use to make the extrapolation— that the odds against two independent events is the multiple of the odds against each event— is very well tested.

    We can be even more confident of extrapolating over all of life, because in some ways HIV itself has mutated as much as all the cells that have ever existed on earth. The mutation rate of HIV (and other retroviruses) is at least ten thousand times greater than the mutation rate of cells. The much higher mutation rate of HIV gives it an evolutionary advantage over cells that increases dramatically if multiple changes are needed. For cells of higher organisms, each nucleotide of DNA has at most a one in a hundred million (108) chance of mutating. 7 The odds of getting any two particular nucleotides to change in a cell in the same generation is that number squared, or one in 1016. Any good bookie could do the math to see that it would take about 1040 cells to generate all possible six-nucleotide mutations. 8 On the other hand, when HIV replicates, each of its nucleotides has a one in ten thousand (104) chance of mutating . Two particular nucleotides changing at the same time in the virus would have odds of that number squared, one in 108, and so on. So to generate all possible six-nucleotide mutations in HIV would require only 1020 viruses, which have in fact appeared on earth in recent decades. In other words, while we have studied it, HIV has run the gamut of all the possible substitution mutations, a gamut that would require billions of years for cells to experience . Yet all those mutations have changed the virus very little. Our experience with HIV gives good reason to think that Darwinism doesn’t do much— even with billions of years and all the cells in the world at its disposal.

    Incidentally, the results with HIV also shed light on the topic of the origin of life on earth. It has been speculated that life started out modestly, as viral-like strings of RNA, and then increased in complexity to yield cells. The extremely modest changes in HIV throw cold water on that idea. In 1020 copies, HIV developed nothing significantly new or complex. Extrapolating from what we know, such ambitious Darwinian early-earth scenarios appear to be ruled out.

    There are some very powerful statements and assertions in there by Behe. But of particular note is the concluding paragraph. There would seem to be very good reason to believe that if some self-replicating viral-like strings of RNA “emerged” (however they emerged) that they would do little more than spin their wheels and run in place as the HIV virus has done — if the only motivating force is random mutation and natural selection.

  5. Brad Nelson Brad Nelson says:

    Behe has now entered the part of the book where he is explaining “non-random” as the most likely explanation for the cell’s complex systems. Near the start of his explanation is this:

    Instead, I conclude that another possibility is more likely: The elegant, coherent, functional systems upon which life depends are the result of deliberate intelligent design. Now, I am keenly aware that in the past few years many people in the country have come to regard the phrase “intelligent design” as fighting words, because to them, the word “design” is synonymous with “creationism,” and thus opens the door to treating the Bible as some sort of scientific textbook (which would be silly). That is an unfortunate misimpression. The idea of intelligent design, although congenial to some religious views of the universe, is independent of them. For example, the possibility of intelligent design is quite compatible with common descent, which some religious people disdain. What’s more, although some religious thinkers envision active, continuing intervention in nature, intelligent design is quite compatible with the view that the universe operates by unbroken natural law, with the design of life perhaps packed into its initial set-up.

    • Timothy Lane says:

      Properly speaking, intelligent design as a theory (to the extent that it has yet reached that status; it certainly hasn’t been validated yet) makes no assumption about who or what the designer is. Some years ago, there was a short seminar on the subject at ConGlomeration (the regular SF convention in Louisville) on the subject, and at one point the speaker (an SF fan also noted for urging that the movie 1776 be shown at InConJunction, held yearly at Indianapolis on or around July 4) noted that someone who pushes a specific form (such as the Genesis creation story) isn’t really talking ID theory.

  6. Brad Nelson Brad Nelson says:

    Check out this flow chart of endomesoderm network. As Behe notes, this is “an illustration of the genetic regulatory system that turns on the genes that control the construction of a tissue called the endomesoderm in sea urchins. Notice the obvious, impressive coherence of the drawing. The figure is intended to be strikingly reminiscent of a complex electronic or computer-logic circuit, because in essence that is what genetic circuits are.”

    Holy smokes. Remember, this is just one tissue, an it’s the control system for the building of the one tissue, not the actual instructions to build it. It is analogous to the foreman instead of the workers.

    • Timothy Lane says:

      That looks like a flowchart for how Obamacare operates. Come to think of it, does Obamacare prove that random mutation can create complex systems? It certainly doesn’t qualify as intelligent design.

      • Brad Nelson Brad Nelson says:

        Yes, no doubt a flow chart on its own is not proof of a *working* design — as is likely the case for Obamacare.

        But what even those who don’t espouse intelligent design admit is that you take one protein out of that entire network of control proteins (which are part of a complex system that does indeed work) and the whole thing falls apart.

  7. Brad Nelson Brad Nelson says:

    I’ve made it to about the end of this book. Or, I should say, I’ve made to the end of the relevant stuff (although the appendix might have some very good and detailed information).

    It seems only a matter of time until these types of books fall of a cliff. This one eventually did about 4/5 ths of the way into it. But to Behe’s credit, it was a large cliff from which to fall.

    I highly recommend this book whether you are into intelligent design or not. Although Behe’s alleged purpose is to make an argument for intelligent design (more on that later), what you get in the midst of this is one fascinating discussion on the latest discoveries in cell biology. You will learn a lot about the basics of what is going on inside the cell. You can treat this book as a biology overview.

    And Behe does a very credible job of fairly and concisely showing “the edge of evolution.” That is, he shows where and why evolution by natural selection, driven by point mutations, works. And he credibly shows where Darwinism doesn’t work. And he does so on both counts in a fairly easy-to-understand manner. I would willingly volunteer to edit his next book and help get rid of some of his ambiguity and obscure phrasings which are unnecessarily sprinkled throughout the book. But for a book of this type he has generally done an excellent job.

    Where the book falls off the cliff is at the end where it seems he doesn’t even believe in his own theory. If there is an intelligent designer, I would expect him to do some designing. And that means erasing the blackboard and writing in what you want, etc. But Behe, while making a case throughout the book of intelligent design, at the end reduces this designer to working through the laws of physics. It was the designer who gave a nudge to the planetoid that hit the early earth and created the earth/moon system – another of the “fine tuning” aspects of the universe. This seems a clumsy use of I.D. theory. And as soon as he presents the designer as basically being a great pool shot artist by playing planet pool (shades of the Red Dwarf episode “White Hole”) then it all just seems a little silly and improbable. If the designer is simply going to act through natural means, what use then is there for a designer?

    This led me to wonder if Behe actually believes in his own subject. Is this just a way to sell some books to a Christian audience? And when it comes to positing how life started, again he simply has the designer playing a game of cosmic target shooting where the designer, using the existing laws of nature, causes a few molecules to come together in the right way via cosmic rays blasting in the right place and at the right angle. But this idea seems absurd and out of phase with the entire intelligent design theory, including Stephen Meyer’s critiquing of the various supposed “natural” ways that life could have started (which all seem very improbable). And although Meyer’s views came in a later book (I think), those views were certainly generally known by those in and around intelligent design.

    Near the end of this book, after falling off what now seems like an inevitable cliff for these type of books, Behe, for some strange reason, goes on and on talking about the theory of the multiverse. Why? I don’t know. My hunch is that after one is done punching holes in Neo-Darwinism, there isn’t all that much one can say positively about intelligent design. This may be why these books, after they are done with the critique of Darwinism, basically have little else to say.

    But I will say that in this book that Behe at least goes further in articulating the implications of ID then Meyer ever has. Behe traces the “edge of evolution” down to the “Class” level of biological classifications. This is the level where there is obvious cell specialization (tissue specialization, I guess) which would, in his theory, require a specific design for this type of cell. Below that (to the classification of Order and then Family) he does not say because he says there is still much to learn (fair enough). Natural selection may or may not be enough to account for the biological changes on the level of Order, Family, Genus, and Species.

    You will walk away from this book with an awe for biology. And you will come away knowing fairly certain that the idea of gradual change is problematic regarding some of the more complex structures (which defines nearly all of the cell). This chart showing just the mode and method of the proteins to regulate the building of one type of tissue (just the regulation, they don’t do the actual building) in a sea urchin looks very much like an electronics schematic. This is like a complex wiring diagram. A program. Imagining how something like this is put together in a stepwise fashion is problematic. Whether an intelligent designer is needed or not is another issue. Behe thinks that one is required (which he coyly first calls “non-random” mutation).

    But one of the problems inherent in the idea of an intelligent designer is that so much of the history of life on earth is given to chance and contingency. One can imagine a designer getting things rolling 4-1/2 billion years ago, creating a cell, and plunking it in the oceans. And then this designer perhaps tinkers with his creation every few million years, steering it here or there as desired. He then gets an inspiration (which is his due) and creates a whole bunch of different basic body plans and sets them going to start the Cambrian explosion.

    But, at best, we get the image from this as an intelligent designer tinkering with his ant farm, not God Almighty. If this designer is specifically interested in Earth as the cradle of life — perhaps unique in all the universe, as Behe posits — then why let destructive astroids or comets wipe it out every few million years? The problem, as I see it, eventually becomes having to impart too many motives and small adjustments to the designer — when we are actually in the field of creation, and not just letting things remain theoretical with a word such as “intelligent designer” — that it might have been more parsimonious to just put it all down to natural laws operating in ways we haven’t thought of yet.

    Behe may be the best proponent of intelligent design but at the same time its worst. The critique of Darwinism seems solid and comprehensive. But when you hand off to the concept of “intelligent designer” then one has circled right back round to the inherent problem faced by Neo-Darwinism where details are glossed over and all contingencies are covered by just saying “things evolved.” That seems to be inherent to the ID movement as well. They just say “things were designed.”

    I’m not satisfied with either, which makes sense at this point because we have so much more to learn. Either theory has huge weaknesses. Perhaps some third or fourth theory will be a better fit with the facts. As it is now, it all seems speculation of the type one would hear on the Art Bell show.

    • Timothy Lane says:

      I can’t remember if it was Behe or someone else who mentioned this, but it has been noted that Yahweh tended to prefer using natural processes for his own miracles when possible — for example, using a strong win to blow the Red Sea (or whatever) aside for the Hebrews to cross.

      • Brad Nelson Brad Nelson says:

        Well, that certainly could be the case. I found it fascinating, however, that Behe (a Catholic) so shied away from the idea of God Almighty just twitching his nose (Bewitched-style) and thinking something into creation. The end doesn’t ruin the thinking he did in previous chapters. But it did seem to let the air out of his entire argument — even to the point that it had me sincerely wondering if he was just writing to an audience.

  8. Brad Nelson Brad Nelson says:

    One thing I will say is that I am persuaded (but not yet convinced) that some kind of “forward-looking” apparatus (including mind and intention) is needed in order to explain the complex systems that we see in the cell. Given that you can send a single electron through a double-slit experiment and it will actually somehow interfere with other electrons (creating a wave interference pattern) that are not yet sent through the slits is testament to the apparent fact that even an electron can be “future looking.” There may be other ways to explain that experiment but that is certainly one implication. Time is indeed like rubber.

    But if Behe is correct, and I think he is, in order to explain life as we see it we have to combine Darwinian processes with other processes — known or unknown. And as he says about evolution, of course it happens and is a formative influence via the simple idea that that which survives will then tend to multiply. This is the aspect that is probably quite repugnant to many, an issue that Behe does at least address when he says, and I paraphrase, that the harshness of life is not an argument against the way things are.

    And the way things are that death is actually a huge driver in regards to shaping life — the real essence of Darwinian theory. Is there something pushing from the other end, something that intentionally pushes life-giving attributes into the cell and thus into life? There could be. Be either way, the story of life and our existence isn’t all sunshine and roses, intelligent designer or not.

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