Thursday, May 1, 2008

113. Skirting evolution doesn't change it

Our latest healthcare statements included an insert on antibiotics, entitled, "Know When to Say No to Antibiotics." This proclamation is two-fold. First, there is an overuse problem in the prescription of antibiotics- often for inappropriate illnesses, those which our bodies can handle naturally. Secondly, they are often described for illnesses in which they are ineffective, such as viruses. However, the motive is as much financial as it is good medicine, and, inevitably the health insurance company can save itself a considerable amount of money if these prescriptions are dispensed less often (some estimates are as high as $18.5 million per year for antibiotics).

But that is not what attracted my attention, rather it was the proceeding explanation, which reads, "Bacteria continue to change and grow into ‘superbugs' that do not respond to antibiotics, leading to a growing antibiotic resistance problem." Bacteria do change, but they do not "grow into superbugs." They genetically change over time in response to the selective pressure placed on their environment. They do not change into extraordinary microorganisms capable of leaping small buildings in a single bound, they change into a genetically different, or "variant" bacteria. In short, they "evolve." And I thought it was interesting that the insurance company avoided that word like the plaque.

More specifically, as the bacteria are attacked by the antibiotics, most are killed- which is fortunate, because it leads to our recovery. However, in the course of rapid reproduction, mutant bacteria, some of which may be resistant to the bacteria, are born (or replicated), and survives to reproduce and pass on its genetic makeup (other mutants die or offer no resistance to the antibiotics). Subsequently, these resistant bacteria, those that survive, are passed on to other individuals. In scientific terms, they are selected. And, obviously, since the mutant bacteria are resistant to the original antibiotic, the prescription is ineffective and scientists must now develop another antibiotic. Again, there is nothing "super" about them, except they are more resistant to our current antibiotics. There are more complicated methods in the resistive undertaking by the bacteria, such as transformation and plasmid exchange, but the effect is the same- its genetic makeup has changed. PBS has adeptly referred this process as the "evolutionary arm race."

The process I described is, granted, a bit simplified, as the entire endeavor is complicated by the intricacies of science, such as the debate to what extent the bacteria suffers a "cost of resistance." In other words, to what extent are the resistant bacteria less fit in the absence of antibiotics in the adaptation of their genotyopes? The entire exercise is a wonderful exploration into science- including our immune system, microorganisms, population genetics, mutations, and yes, that nasty word- evolution.

The religious perspective on the subject is a bit interesting, as this is of considerable importance in addressing and refuting the theory of evolution. The explanation from such groups as Apologetics Press, Answer in Genesis and The Discovery Institute, differ in how they attend to the idea. While most do not debate that the bacteria evolve, they dispute the mechanism and the significance of the change. For example, here is the conclusion drawn in answersingenesis.com:

"The mechanisms of mutation and natural selection aid bacteria populations in becoming resistant to antibiotics. However, mutation and natural selection also result in bacteria with defective proteins that have lost their normal functions.

Evolution requires a gain of functional systems for bacteria to evolve into man-functioning arms, eyeballs, and a brain, to name a few.

Mutation and natural selection, thought to be the driving forces of evolution, only lead to a loss of functional systems. Therefore, antibiotic resistance of bacteria is not an example of evolution in action but rather variation within a bacterial kind. It is also a testimony to the wonderful design God gave bacteria, master adapters and survivors in a sin-cursed world."

This explanation clearly focuses on the debate I referred to previously on the "cost of the resistance." It is a "gap argument," in which one aspect of science is used by non-scientists to justify their religious conclusions. It is obvious that science has it right otherwise antibiotics and other treatments would not be as effective as they are. And even if there is debate on the exact mechanism of mutation (scientific studies indicate that microorganisms are able to overcome the harmful side-effects of resistance), I cannot help but to wonder the outcome if they would apply the same scrutiny to their own beliefs and principles.

In the 2006 Organization for Economic Cooperation and Development (OECD) study, American students ranked 29th in science in comparison with 57 other countries. As exemplified by my medically-based insurance company avoiding and sugar-coating the science that affects our own bodies, perhaps part of the problem is that we are even afraid to admit that science exists. Maybe it could be better understood in a comic book, or video game- "Superman versus the Superbugs!" The point is that you can only "dumb it down" for only so long before people become...well, you know.

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