Tuesday, August 09, 2005

Once More Into the Primordial Swamp

As the active trackbacks on my previous posts on the topics of creationism, intelligent design, and evolution are showing, my viewpoint is being spread across the web to several interesting locations.

One of the more vocal ones seems to be KipEsquire of A Stitch in Haste, who blogged the following:

It's interesting to watch the flames of fraud jump from the totally debunked "irreducible complexity" fallacy to the new nonsense of "sticky species," the idea that, since we have never seen a species "morph" from, say, a fruitfly into a fruit bat, we are therefore guilty of "faith." Again, it took nature a billion years to make a bacterium and 4.5 billion to make us. Any progress we've made, even going from wild boars to domestic pigs or from prehistoric maize to modern-day corn, is pretty damn impressive and pretty damn conclusive given the sheer enormity of geologic time. "Faith" has nothing to do with it.

Kip's argument in this case is that the fact that human beings, through selective breeding, have been able to change maize into modern corn and wild boars into domestic pigs. That is a true statement.

However, Kip then generalizes those changes to indicate that evolution (as strictly defined, the fact that expressions of observable traits in a population over time tend to change in response to environmental pressures) is solely responsible for the diversity of life on our planet. That has rather significant difficulties that require a strong degree of "faith" to accept.

The problem with using the change of maize into corn, for example, can be summed up very simply in this reference, which talks about the changes (emphasis points mine):

"In the genes we looked at, early farmers did not 'change' anything within the gene," said Viviane Jaenicke, a researcher at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. "All (of the genes) were already present in the teosinte (corn's precursor) populations. All the early farmers did was to select teosinte plants which carried the alleles they were interested in. And this selection process created then the maize. So it is not 'engineering' but a selection process."

More exciting to Jaenicke is the fact that she and her colleagues were able to gather enough DNA from a 4,400-year-old ear of corn to study. They were surprised to find that genes found in modern-day corn were already present in the ancient corn.

What Kip is talking about is selective breeding, which is identifying traits that you want to perpetuate in a given population and arranging mating patterns to do so. This intensifies certain traits, but at the same time, increases the dependency of the population on outside assistance. For instance, teosinte, the genetic precursor of corn, grows almost anywhere, including areas of very poor soil and low rainfall. Modern corn, as anyone else who grew up on the prairie knows, requires very nutrient-rich soil and an enormous amount of water to survive and to thrive -- both of which exceed the capacity of unassisted nature to provide under most circumstances. Furthermore, although maize can crossbreed back with other teosinte and its other derivatives, doing so reduces and dilutes the advantageous traits that maize has. Again, there are good reasons that college and high school kids are paid good money to go through and detassel corn in the summertime -- any mixing of genetics often results in a poorer, less-advantaged product. "Hybrid vigor" does indeed exist, as we see in the superior disease resistance of mutts as compared to purebred dogs, but a mutt is rarely, if ever, as good as its purebred parents in terms of their selected traits (i.e., crossing a Chihuahua with a Great Dane gives you a dog that's neither small enough OR big enough).

Importantly, though, as the article points out, in selective breeding, the net of the genetic material itself does not change -- only the way in which it is expressed. That is an excellent proof for evolution as strictly applied, since it shows definitively that environmental pressures (in this case, human intervention) can cause changes in the traits observed in a population, but it is an extremely poor one for arguing that evolution is responsible for both the vast observable AND genetic differences among life forms on this planet -- after all, the base genetic material does not change, the changes made in trait expression are often counterproductive to survival and reproduction, and the changes, assuming they do confer an advantage, are diluted when divergent lines are crossed.

In short, in order for selective breeding to be an absolute proof of evolution as they apply it, the only difference between any forms of life on the planet would have to be the expression of genes, not the number or type of genetic material. Furthermore, we would have to be able to crossbreed with any other form of life as well.

Clearly, that is not the case; thus, at this point, the evolutionists start bringing in the idea of "genetic change", meaning that the actual genes and chromosomes themselves of organisms were altered through mutation, addition (i.e., bacteria and viruses work by inserting their genetic sequences into the DNA of their host cells), or crossbreeding (donkeys and horses, which have different numbers of chromosomes, can be crossed to produce mules with the chromosomal characteristics of both parents).

However, genetic change is in and of itself a cantankerous process. When you consider what happens when you mess with the genetic material, the default answer is "lethal" (most individuals with genetic abnormalities die in utero), then "obviously impaired" (the laundry list of human genetic disorders), followed closely by "sterile" (i.e., a mule), then "impaired, but not immediately observable" (i.e. Huntington's disease), to "not impaired, but not advantaged", and finally to "advantaged by genetic change" -- a miniscule fraction -- you have to wonder how such a horribly inefficient process produced such enormous and functional diversity of life.

Of course, even an inefficient process can generate sufficient output if you do it often enough, which accounts for the next refuge of evolutionists -- "geologic time". According to their argument, since the earth has been around for 4.5 billion years, give or take a few hundred million, over that period of time, enough "advantaged by genetic change" has taken place that we made the leap from protozoa to primates.

Again, though, from what our friends the geologists tell us, we can see that there are a few issues with that. First off, no one knows exactly how long the earth has been temperate enough to support life in the first place. We know that bacteria can survive near the boiling point of water, for instance, but that's a far cry from the temperature of molten rock, which is at best how the Earth started under most theories. Furthermore, it is commonly believed that our planet, as it cooled and solidified, was atmospherically very similar to Venus -- again, not conditions exactly conducive to supporting life, and again, no one knows for how long. Finally, if that weren't bad enough, the geologists tell us that Earth has been racked by several sudden and cataclysmic events -- meteor impacts being one of the largest -- that so drastically changed planetary conditions, it is likely that almost all, if not all, life was wiped out during one or more of them.

In short, you don't have 4.5 billion years to explain the genetic diversity of life on Earth. Furthermore, you have to take into account not only that, but that you may have had to repeat the process multiple times from the ground up, taking into account the dizzying arrays of climatological, environmental, and bioprocesses that could have been involved. At some point, the probabilities of all these events converging simply become outrageously small.

Again, anything's theoretically possible. At some point in time, scientists may manage to create an organism from the aggregation of organic chemicals. But, from a selective-breeding-as-proof standpoint, the argument is stronger that life started out as a group of proto-critters that then diversified in traits via strict evolution, versus the "bacteria became humans" argument.

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