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Evolution vs. Common Sense
Once again "evolution" has been forced onto the stage as Exhibit A for both sides in the Culture War. It seems the State of Kansas has decided to leave it up to local school boards whether or not to teach evolution as fact. This, naturally, has enlightened sorts in an uproar. I will not take sides in that specific battle, but this seems an opportune time to say a few things about evolution that need saying.
Evolution is a theory. It is a theory of natural development which seems reasonably well supported by the physical evidence. But, as theory, it cannot be treated as received truth. So many on the "progressive" side of this debate appear to want desperately treat evolution as religious belief, as something that cannot be challenged. To seriously express doubts as to the soundness of evolutionary theory is akin to putting on a tractor cap, turning on NASCAR and marrying your sister. Surely only a redneck/fundamentalist/moron could seriously doubt evolution.
I myself am rather agnostic on the core issue. Both the physical evidence of fossils and the theoretical framework laid out by Darwin and his successors seem convincing. On the other hand, logical inconsistencies seem to keep popping up that cause me to think that evolutionary theory cannot be as neat and tidy as we are led to believe. I would like to take a moment to look at a couple of these inconsistencies that I cannot ignore, and cannot quite get around.
But first some definitions. "Evolution" by itself is a relatively harmless concept which suggests that species change over time, and that a careful study of the physical evidence indicates that these changes have proceeded steadily from the dawn of life on earth to the present day. The most commonly accepted "engine" of evolution, the agent of change, is "natural selection". Commonly known as "the survival of the fittest" this theory says that random genetic mutations produce physical or behavioral characterisitics which allow some members of a species to better adapt to changing natural conditions. Those whose characteristics are most suitable to a given environment are most likley to thrive, hence more likely to reproduce and pass those characteristics along to the next generation. While this notion makes no sense at all when viewed up close, its relentless proceeding over millions of generations and hundreds of millions of years in theory provides enough opportunity for change to explain evolutionary change.
I am not sure that natural selection holds up under scrutiny. First, as theories go, it is inherently logically flawed. It is at heart a tautology, a circular truth. Its operating premise is that whatever creature survived was by definition more fit than the one that didn't. It thus uses the results of evolutionary history to posit the cause of evolution, rendering it essentially unprovable as a causative theory. This confusion of cause and effect is rampant in evolutionary theory.
For example, many scientists have recently begin to suspect that birds in fact evolved from the dinosaurs, specifically from quick and nimble later dinosaurs such as Velociraptor. The physical similarities are striking, and the evolutionary timing seems to makes sense. But if you sit down and try to understand how this evolutionary path would have worked in the context of natural selection, you run into problems. From an evolutionary standpoint, flight must have preceded feathers and extra light bones. One can justify flight in the absence of feathers from a natural selection perspective, but it is almost impossible to justify feathers in the absence of flight. It is very difficult to see what possible evolutionary advantage feathers offer on their own terms, a suspicion affirmed by the fact that no creature exists today with feathers that does not fly (or whose ancestors did not fly). The development of feathers prior to flight would indicate "planning" for flight, which would run completely against the premises of natural selection.
There were dinosaurs who developed the ability to fly without having feathers, so let us assume that the evolutionary path of birds led first to flight, and then to feathers for faster, higher, and more flexible flight. The physical record doesn't necessarily support this, but let us accept it for now, for the sake of the argument. This leaves us with a first step of understanding how dinosaurs developed wings. This is a curiosity, because wings are a very particular thing. The physical characteristics required to allow the flight of a very heavy boned and unfeathered animal would seem remarkably unlikely to have occurred by random selection based on genetic mutation. This is especially so since wings in theory evolved from arms, or forelegs. The timeframes of natural selection would mean that a very long time would have elapsed during which these appendages were rather useless as legs/arms, and not yet usable as wings. This sounds to me like a recipe for extinction, not evolutionary advantage. It is precisely this transitional period of trans-species evolution that nobody likes to talk about.
The key to natural selection is that it occurs in small pieces over a large period of time. There was not a dinaosaur born one day who just so happened to have a pair of mutated legs that also just so happened to be perfect wings. It would have had to happen over countless generations of dinosaurs. And this again makes us run into the planning vs. natural selection idea. What possible natural advantage could a dinosaur have from wings that were half-formed but not yet useful for flight? I can't think of any. What I am left with is a physical record that pretty clearly shows that birds and later dinosaurs are related, but no satisfactory way to explain that dinosaurs became birds through the process of natural selection. This is one small example of the sorts of conundrums one runs into frequently when thinking about evolution and natural selection. It may be that there are very logical explanations, but that I am simply too ignorant to have heard them. I just wish that the questions would be asked out loud and in the open.
The reluctance of the scientific community to allow debate on this subject, or even to allow questions to be asked, is most unscientific. Their hysterical reaction to any effort to provide an alternative point of view has the whiff of a jihad about it. It's almost enough to make one suspect that the desire to remain ensconced in their comfortable paradigm outweighs their committment to truth.