Monday, November 2, 2009

Evolution In A Can

As I returned to town hall after another day of serving the local citizens, I stopped in the restroom, as I often do, to finish the processing of some of the day's coffee and iced tea. As I closed the door, I saw a can of Lysol on the shelf by the sink. It said, quite proudly and in big letters, "Kills 99.9% of germs." I looked at it and said "What about the last point-one percent?" (SEE NOTE 1)

That got me to thinking about how easy it is to show evolution to people, and why it is important that we understand it. It is this simple:

If we spray that Lysol on a germ population, we knock out 99.9% of them (SEE NOTE 1, if you have not yet done so). That last .1% then has no competition for resources (space, food, etc.) and can reproduce more freely -- all this as a result of a genetic coding that gave it a competitive advantage at this point in spacetime (that genetic coding may or may not have ever had any influence on its reproductive ability before now -- SEE NOTE 2).

With that resistant strain having the chance for wider distribution on that surface, it also gains a better chance of coming into contact with something -- like you -- that might transfer it to another surface where it can establish itself and start the whole process over again.

This is evolution in a nutshell (or on a doorknob, if you will). It is, at its core, a very simple process, and one that is easy to show. Where it gets more complicated is with, of course, more complicated organisms. This is why you don't see major changes in a species from one day to the next. It takes place at the level of DNA -- of the many combinations of just four nucleic acids contained in two polymer strands (I'm trying to keep this simple, so I will stop there). For DNA changes to survive long enough to express themselves at the species level of complex organisms take huge amounts of time.

If evolution is this simple, why don't more people understand it? The answers are manifold and complicated, but I will give you the main ones:

1. Scale. Humans have evolved to deal with things on a medium scale. That is, our senses pick up certain-sized things (including sound and light wavelengths). We cannot see DNA with the naked eye, nor are we alive long enough to easily grasp things that take more than our lifetime (SEE NOTE 3). Evolution involves both the very tiny AND the very large. Double whammy.

2. Education. It is no coincidence that evolution is least understood in populations with lower education levels. It takes a certain level of basic science education to understand evolution, and many other important aspects of the real world (SEE NOTE 4).

3. Fear. Humans are afraid of things we don't understand, of the unknown, and of change (change often means an unknown future, after all). Evolution presents all of these things. It can be hard to understand (mostly, IMO, because of inadequate education and/or scale issues), it involves an element of the unknown (of the past and the future), and it IS change. The real world is a scary place, and evolution brings much of that scariness to the forefront. Some people prefer to pull the blankets up over their heads and hope/pray the monsters will go away. Denial, however, is not a valid strategy for survival.

If you find evolution to be a fuzzy concept (even after my explanation), you should start with Richard Dawkins' book, The Selfish Gene. It will help you to understand the process much better, and just may change the way you look at the world... including a can of Lysol in the bathroom at work.

XXX

NOTE 1: The more astute reader may ask what that 99.9% actually means. Is it 99.9% of the number of individual organisms? Or is it 99.9% of the types of organisms? Those are two very different conditions. Checking the Lysol web site (http://www.lysol.com/products/disinfecting-sprays/lds-disinfectant-sprays/) gives us the following relevant information: "LYSOL® Disinfectant Spray is an EPA registered disinfectant that kills more than 99.9% of illness causing bacteria and viruses on environmental surfaces in your home. " It doesn't really answer our question, does it? Either way, we see that it gives a competitive advantage to the more dangerous germs.

NOTE 2: This particular coding may very well have been a random mutation, either old or recent, due to things like exposure to the sun (radiation causes genetic mutations) or just a plain old screw-up in the genetic replication process of the organism. It happens, and this is an important point in understanding the process of evolution -- not every change is a result of selection pressures.

NOTE 3: I view this as a sort of wavelength issue, for illustrative purposes. If one were to plot the average human lifespan and the time it takes for a given species to become another species (something that is a matter of great debate and study), as waves on a graph, the wavelength of evolutionary change would be so much larger than that of a human lifespan (yet tiny compared with a wavelength representing, say, the age of the planet) that it would be extremely rare for them to intersect. Add to this the fact that such changes are extremely hard to detect and you can get an idea of why we don't see speciation in complex organisms. It's largely a matter of basic math.

NOTE 4: Americans are lagging behind in this important area. Our overall substandard science education hurts our nation's ability to cope in the world economy, which hurts our social and political power. American "patriots" should be putting science education at the very top of the priority list if they want to see a strong America with a leadership role on the world stage in the future.

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