Wednesday, June 27, 2007

More ID debunking, 10 shots across the bow

kw: book reviews, nonfiction, evolutionary debate

I must be getting saturated. For the first time, I've read a book that had nearly nothing new for me. This is not to fault the authors; it is a sign to me to reduce my attention to the creation-evolution debate.

Cameron M. Smith and charles Sullivan, both professors, both popular science writers, both of whom write for Skeptical Enquirer, collaborated on ten essays under the title The Top Ten Myths about Evolution. I can summarize the ten chapters thus (in my own words):
  • Survival of the Fittest — As Solomon said, "The race is not always to the swift, nor the battle to the strong"...and a wag added, probably Ambrose Bierce: "...but that's the way to bet." The common understanding of "the fittest", taken to an extreme, would result in a planet with a very simple ecology: Lots of some plant, probably a grass, lots of some grazer, and a single hermaphroditic predator who gets to have it all to Urself. The 10-20 million visible-sized species that inhabit this planet show that there are many ways to define "fit". My favorite example: the common blacksnake is a more efficient predator than any rattlesnake species in a ranch setting, which is why rattlesnakes are seldom found near dwellings.
  • It's Just a Theory — So is every single scientific principle, but we bet our lives on the Germ Theory of Disease, and on Antibiotic Theory, all the time (except Christian Scientists); the Engineering principles used to design the bridge you just drove across are based on either the Theory of Trusses, or on Finite-Element Theory of Stress (if it looks like a trestle, it is the former). A theory is a model of the way something works, which has been tested by a lot of scientists who'd just love to get a Nobel Prize by proving it is a bad, incomplete, or inadequate model...but so far they can't do so. The "theory of Evolution" is actually "descent with modification" (Darwin's first term for it) or "natural selection" (his second). These are proposed mechanisms to explain why life changes...and it has been shown to change. Evolution is a fact, or actually, a collection of millions of facts; it is Natural Selection that is the theory used to explain the facts.
  • The Ladder of Progress — Where are all the Trilobites? The last one died out a quarter-billion years ago, and every ecological niche that once supported a Trilobite now supports a Crab, a Lobster, or some similar critter with a lot of legs and a hard exterior. Where are the Neandertals? There are three choices: our ancestors ate them or slaughtered them (depends on taste); or ate everything they could eat (sort of like the blacksnakes and rattlesnakes above); or interbred with them but swamped their characteristics by outbreeding the mixed descendants. When Cro-Magnon came on the scene, it was one of at least four hominid species running around; the others gradually vanished, like all other apes are vanishing today. Cro-Magnon went through a few significant changes in social behavior and tool use to become "modern humans". But is this some kind of directed progress? No, rerun the scene, perhaps with a slight delay in C-M development, and today Neandertals might be running the show (see relevant Geico ads for a cute take on their abilities).
  • The Missing Link — There are a few sedimentary sequences that show a set of species changing through time. In one case I've seen, the clams near the bottom of the layer have lots of ridges on their shells, perhaps 25 or so, but the number varies from 20 to nearly 40. Midway through, there are fewer ridges, and they are a little thicker and more pronounced. The range is about 15 to almost 30. Some clams at this level look nearly identical to some deeper ones. At the top, the number of ridges ranges from 12 to at most 20, and they are much heavier. Some of the "top" clams with 20 ridges look a lot like the "bottom" clams with 20 ridges, except for having thicker shells. Such a sequence is called a Cline. Over less than a million years, the environment gradually changed to one with heavier surf (steeper coastline?), and the clams changed to accommodate. OK, now. You are given a heavy-shelled 15-ridged shell and a thinner-shelled 28-ridged shell, and told only that the second one is a million years older than the other. Are they members of the same species? Suppose you are then shown a shell identical to the 28-ridged one, taken from a layer the same age as the younger one, but several miles away, where the environment didn't get as rough. Is this clam a different species from the 15-ridged clam of the same age? Answer questions like that first, then consider where on some "ladder" of progress these clams fit. There is no ladder.
  • Evolution is Random — When energy flows, things tend to self-organize. Life has been defined as a self-replicating, evolving phenomenon that is powered by energy flows in environments that are far from equilibrium. Nearly all life on Earth is powered by sunlight, and less than 2% of the sunlight that hits the planet, at that. Photosynthesis is only 1-2% efficient, and nearly all life depends on green plants and other photosynthetic things (like purple seaweed, which isn't a plant, strictly speaking). Get water spinning in a bucket, then drop in some sand in as random a way as you like; all the sand will wind up in a pile in the middle of the bucket. Sand can't reproduce, nor can whirlpools. But living creatures can. Natural Selection has three elements: reproduction, variation, and selection. Reproduction isn't random (except for promiscuous adulterers). Asexual species produce near-perfect copies of themselves. Sexual species produce offspring that are "half like mom, half like dad, but with grandma's nose". If a couple had twenty babies (it has happened), then statistically 99.9999% of both Mom's and Dad's genes are represented in those twenty offspring...but it's a tossup as to which genes went where. Since both Mom and Dad have some 30,000 genes, it is a pretty sure bet that every gene of both parents is out there in at least one child. However, minor changes to the genes occurs with sufficient frequency that every child has 50-100 differences scattered along his or her DNA, that are not present in either parent...or weren't when they were born, anyway. Since only 2% of our DNA is used for making proteins or regulating their production, it is likely only one or two genes are actually affected. Most such mutations make no difference. Some are bad (a very few kill), some are helpful (better digestion, or eyesight, or strength). These variations are truly random. OK that is reproduction and variation. Now, how about selection? Put a child out into the world, provide education and training, and what do you get? You hope to get grandchildren. Maybe you don't. If not, whatever genetic inheritance that child had was selected against. An elm tree produces billions of seeds every year. Only one or two seeds, of all the seeds in a 150-year lifetime, is likely to become a mature tree. For elms, selection is a huge factor. It is not random, by any means. The environment destroys 99.99999999% of all elm seeds; only a very lucky few go on to produce grand-"children" for the old elm. Were selection less intense, an aged elm would not grow eighty feet tall, would produce just a few seeds, would not need much strength to withstand wind or rain or herbivores. It would look more like a moss, which is adapted to a much less "selective" environment. If there is a direction to evolution, selection provides it.
  • People Come from Monkeys — It is more accurate to say that people come from apes, but it is most accurate to say that people are apes. Humans aren't the largest apes, gorillas are; they aren't the strongest apes for their size, orangs and chimps are neck-and-neck for that distinction; humans aren't the fastest apes, gibbons are (when swinging through the trees in a way Tarzan could only envy). Humans have these special characteristics: upright stance, which helps them see farther without climbing and frees the hands for carrying or working while walking; nearly no hair, so they can befriend fire safely; high intelligence so their social skills are unsurpassed; memory (including for thousands of the noisy symbols we call words) that enhances both social and technical skills; the most efficient hand among apes and good hand-eye coordination; and great endurance so they can run down everything except the dog and the horse. The sense of smell is less acute, a benefit in crowded social conditions, but the other senses are the same as the other apes: good color vision, binocular vision, keen hearing, taste and touch. Every ape species is seen to be much more like humans than any monkey species.
  • Nature's Perfect Balance — Give any environment a few millennia of stability, and it will develop a well-balanced ecology. Ever hear of ecological succession? After a forest fire or landslide, the disturbed area goes through several stages; one common sequence is shrubs-birch/poplar-oak/maple. At any point in the sequence, it may look like a balanced, stable ecology over a period of a decade or two. But over a longer period, it is seen to be an ecology in transition. Old growth forest appears stable, and it is, until the climate changes, or a wildfire clears some hillsides. A rising water table will force conversion of a temperate hardwood forest into a willow/birch stand, then cypress swamp. Nothing is static, including the purported "perfect balance" of nature at any one spot.
  • Creationism Disproves Evolution — Creationism requires a supernatural element. Evolution seeks to explain with no supernatural element. Therefore, they cannot be compared, and neither one can disprove the other. However, no explanation that partakes of supernatural elements can be called a science, because science by definition appeals only to natural phenomena. There is no scientific explanation for a miracle. There is no need to do so. Those who have given their lives to "disproof" have wasted them.
  • Intelligent Design is Science — Intelligent design is negative in emphasis, not positive. ID proposes no natural explanation for the existence of any living beings, and no mechanism other than supernatural intervention for the production of any species now living that did not exist in the past. This reliance on supernatural agents or agencies places ID firmly outside science. This is why ID supporters try instead to show problems with evolution, claiming to be the only alternative. ID is but one of a number of alternatives; the scientific ones have already been disproven, and the nonscientific ones—including ID—aren't in the scientific arena.
  • Evolution is Immoral — Evolution is like the weather. It just is. Whether someone believes in God or Allah or Alien Gene Designers can make no difference. The dinosaurs and trilobites are just as extinct. Life has changed over time. The modern TB bacterium is quite different from the one that existed in the 1800s; antibiotic use has been a selection pressure that resulted in resistant germs that did not exist 200 years ago. The Anopheles mosquito has changed; certain species are DDT resistant, and these didn't exist 100 years ago as they are now; it seems they are new species. Evolution proceeds rather quickly when a new selection pressure emerges. Evolution, or Nature with a capital N, also provides no guidelines for deciding moral questions. The lion that eats a baby gazelle is not immoral. The "natural" is neither good nor bad; the lion must eat to live, and is equipped to eat gazelles and gnus. Murder is a human invention. When a chimp kills another chimp, that is not murder, though it looks uncomfortably similar. However, chimps do have an emotional response to such events, which are similar to our emotional response to murder. Thus, chimps avoid a chimp-killer just as humans avoid or shun a murderer (if we don't imprison him or her). But, this one thing I learned from the book: Plato proved that "God Says So" is not a proper foundation for morality. This seems surprising, but follow the logic. Is God's command the only thing we can rely on to determine that killing another person is immoral? If so, then before God spoke, killing was not immoral and there was no such thing as murder. But if we say instead that killing is immoral, and God has prohibited it for that reason, then we don't need God's order to say that it is immoral; it is immoral whether God says so or not. Some say that great harm has been done because of evolutionary ideas. No doubt this is true. Equally great harm has been done because of religious ideas (do I hear "crusades", the great tragedy of medieval times?). I said evolution, like weather, just is. The persistent, tragic failure of Russian central planning of agriculture for seventy years showed that great evils can be promulgated even by misusing the weather. Morality is about relationships, and our emotional response to them. One fellow was orating about how prostitution ought to be legal; a heckler said, "OK, send me your daughter tomorrow."
That's my take, told my way. The authors go into more detail (in 160+ pages).

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