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Friday, December 25, 2015

The Difficulties in Explaining the Big Leaps in Life's History

I read Bill Nye's book Undeniable: Evolution and the Science of Creation to give a well-known author a chance to change my opinion that there is no compelling evidence for the claim that the blind process of natural selection can explain the astounding wonders of biological complexity (for the kind of reasons I discuss here). Looking at the book's index, I found that only 8 pages in the 298-page book discuss natural selection. I didn't find this surprising, because while there is lots of evidence that evolution (or a succession of life forms mimicking evolution) has occurred, the evidence that natural selection is the main explanation for this progression is actually very weak. Natural selection is a real biological effect, which can explain a few things, such as a change in a population of organisms in which a trait held by the minority becomes a trait held by the majority. But natural selection is not very good at explaining the origin of new forms of biological complexity, contrary to what is often claimed.

Looking at the index's first reference to natural selection, I found immediately a very misleading statement by Nye. He states, “Evolution is also not random; it's the opposite of random” (a misstatement he repeats later). No, orthodox Darwinian evolution is, in fact, quite random. When I do a Google search for “definition of random,” the first definition that comes up is: made, done, happening, or chosen without method or conscious decision.” The synonyms that are listed include “unplanned” andundirected.” Evolution as described by Darwinian orthodoxy is therefore quite random, as very many evolution enthusiasts have themselves told us over the years.

Nye suggests that evolution isn't random because it “selects” fitter organisms. Using the same type of reasoning, we could argue that hurricanes aren't really random, because they “select” lighter buildings to destroy rather than heavy buildings made of steel and brick. We could also argue that forest fires aren't really random because they “select” wooden buildings to destroy rather than heavy steel buildings. Such reasoning about hurricanes and forest fires would, of course, be quite erroneous and sophistical. It is just as erroneous and sophistical for Nye to claim that evolution (as described by Darwinian orthodoxy) is not random just because it “selects” fitter organisms. The real issue in whether something is random is whether it is blind and mindless, without a plan. The type of evolution Nye believes in is utterly blind and mindless, without any plan; so it is extremely misleading for him to describe it as the “opposite of random.”

The first four pages in which Nye discusses natural selection do not give anything like a coherent argument that natural selection can explain biological complexity. In fact, Nye seems to repeatedly veer into attempts to explain natural selection by discussing marketplace and corporate behavior. This is misguided, because corporate and market behavior (such as the “survival of the fittest” of well-designed products) are examples of what is known as artificial selection , which involves conscious decision making and is entirely different from unconscious natural selection. You can in no way validate the power of natural selection by giving examples of artificial selection.

The main problem with believing that natural selection is the main explanation for biological complexity is that the biological world has a thousand marvels of immense coordination, in which components are arranged in extremely coordinated and complex groups of components; but neither natural selection nor random mutations offer any mechanism for coordination. Random mutations can explain why different small components might occasionally arise, but orthodox Darwinism offers no mechanism by which these components would arrange themselves into highly coordinated and complex groups of components. For the orthodox Darwinists there are countless problems of this type: how did nature “climb the staircase” to reach some top level of complex coordination, in such a way so that each step added to the reproductive value or survival value of an organism, so that each step was useful? Under Darwinian assumptions, each step must be useful, or we can't explain it.

One such “climbing the staircase” problem involves the evolution of wings. To the naive mind, it does not appear that a small part of a wing would have any use. Nye tackles this problem, but fails to explain it away. For one thing, his approach involves a kind of cheat. His chapter on the topic is entitled “What Good Is Half a Wing?” Trying to explain just that is cheating, because it is starting halfway up the stairway, when you should be starting at the bottom of the stairway. The question that should be asked is not “what good is half a wing” but “what good is an eighth of a wing” or “what good is a wing stump.” To explain this problem under orthodox Darwinian assumptions, one would need to offer a scenario by which a species might progress through this series: (1) no wing; (2) an eighth of a wing; (3) two eighths of wing; (4) three eighths of a wing; (5) four eighths of a wing; and so forth. One would need to explain how each of these progressions involved an increase in either reproductive value or survival value.

Nye is unable to explain such a thing. He offers two ideas to try to help explain the evolution of wings. The first is that organisms began to develop wings to keep them warm. This doesn't work, because that can't explain the first two steps in the stairway; it can't explain why a species would start to evolve a wing stump or just an eighth of a wing. A wing stump or an eighth of a wing is worthless for keeping you warm. If you doubt this, I suggest the following experiment. Break a chopstick in half, and paste a few feathers on it. Then tape that feathered half chopstick on your shoulders, and go out on a cold night. You will not feel any warmer.

The second idea Nye offers to try to explain the evolution of wings is to suggest that partial wings were useful for gliding. This does not work, for two reasons. A lesser reason is that gliding is only useful for certain types of animals (such as tree-dwellers); but it is believed that birds evolved from reptiles that did not live in trees. The larger reason is that to get even a capability for gliding, a wing must be quite well developed, much more than just a wing stump. So a gliding hypothesis cannot explain why an organism would evolve the first eighth of a wing or a wing stump.

For the orthodox Darwinian, there are countless problems like this wing stump problem – problems of explaining how blind evolution could have reached some improbable target involving a great complex coordination of components. If you shrink the scale, things get much, much worse. The problem of explaining the mechanisms of cellular machinery are vastly more difficult. For example, the basic cellular operation of protein synthesis involves at least six different very complicated components which must all be tightly coordinated: a genetic code, DNA, messenger RNA, ribosomal RNA, transfer RNA, and proteins. The degree of coordination at this microscopic level makes the coordination of muscles and bones in a wing look very trivial in comparison.

How can all this coordination be explained when Darwinian orthodoxy offers no mechanism for coordination? Nye offers no hint, and I do not find “coordination” in the ten-page index at the back of his book. I see in his index only two pages that discuss biological complexity (pages 60-61), and those pages offer nothing to explain it (other than the not very helpful claim that the “speed of sexual selection” may contribute to biological complexity). I also see no mention of “coordination” in the index of Ridley's 600-page textbook on evolution. But I guess that's not surprising, since explaining biological coordination is not something that Darwinian orthodoxy does in any substantive way.

A better book on evolution is Nick Lane's book Life Ascending: The Ten Great Inventions of Evolution. Lane talks about ten leaps that life had to make to get to where it is now, but he sure doesn't persuade a probing reader that natural selection was all that was involved. One of the great leaps he talks about is the leap of prokaryotic cells to eukaryotic cells. Prokaryotic cells are primitive cells, and eukaryotic cells are the vastly more complicated, feature-rich cells which we are made up of. The move from one type to another has been described as like moving from a one-room studio apartment to a millionaire's mansion. We could also explain it as like upgrading from a 1980's version of MS-DOS to the current version of Windows (Windows 10). 


Here is how Lane attempts to describe this change, using not natural selection as the explanation but the weird theory of endosymbiosis.

The world is split in two. There are the eternal prokaryotes and the kaleidoscopic eukaryotes. The transition from one to the other seems not to have been a gradual evolution, no slow climb to complexity...Only a rare and fortuitous event, a collaboration between two prokaryotes, one somehow getting inside the other, broke the deadlock. An accident. The new chimeric cell faced a host of problems...A happenstance solution may have given rise not just to the cell nucleus but also to a tendency to collect DNA and to combine it it in the endless constellations of the magical world around us. Another accident. The world of marvels around us, it seems, springs from two deep accidents. On such tender threads hangs fate. We are lucky to be here at all.

This is the weird theory that seems to be that a very complicated cell arose after one simple cell ate another simple cell and they somehow magically became a nice coordinated cell that was vastly more complicated. It's extremely hard to believe that this would happen by chance. “A quantum leap in complexity by digesting something” is not a plausible theory, particularly since eukaryotic cells are a hundred times larger in diameter than typical prokaryotic cells such as bacteria. That such a theory must be resorted to is further evidence that natural selection is not up to the job of explaining the origin of biological complexity.

Lane's book highlights the fact that the growth of biological complexity is a story of “great leaps.” These leaps include:
  1. The appearance of the first self-replicating molecules.
  2. The appearance of the first primitive cells, and the genetic code they required (a system of symbolic representations).
  3. The appearance of photosynthesis -- quite the marvel, judging from the complexity described by Lane, who describes it as five “complex interrelated systems” that “work in sequence...it's an enormously complicated way to crack this particular nut.”
  4. The appearance of eukaryotic cells vastly more complex than prokaryotic cells – a quantum leap which Lane suggests cannot be explained by a gradual progression.
  5. The transition of life from the sea to the land (hard to explain under current thinking, rather like explaining an evolution from earth-based organisms to organisms that live in a vacuum of outer space).
  6. The appearance of birds, which has the wing stump problem.
  7. The appearance of the human mind (with lots of features that natural selection doesn't explain, because they don't have survival value, as explained here).
Overall, the ability of natural selection and mutations to explain these things is poor. If scientists think otherwise, it's partly because they have long had a habit of underestimating requirements, as Lane does rather laughably when he makes this reductionist claim about the famous “hard problem of consciousness” emphasized by philosopher David Chalmers: “Surely Chalmers' hard problem is actually a problem in biochemistry.” As if some chemical equation could explain how Mind arises from matter.

But the very clannish and dogmatic community of evolutionary biologists will probably continue for quite a while to push the Official Party Line that natural selection explains the origin of biological complexity, in a way rather similar to the way that Marxist dogmas (an Official Party Line) would be handed down authoritatively from Moscow in the years of the Soviet Union. 

Postscript:  See this link for a list of about 50 researchers who are described as "a list of researchers and authors who have one way or another expressed their concerns on natural selection’s scope and believes that other mechanisms would better explain evolution processes." It's a very distinguished group (mostly scientists and professors), and each of them has written a book describing their views. 

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