by Whit Gibbons

September 23, 2002

The beginning of the school year, coupled with recent evidence that creationists still exist, leads me to repeat parts of a column from the last century. My point in doing so is to emphasize that no one in the 21st century should hesitate to educate people about the concept of evolution.

The world is round not flat; it revolves around the sun and not vice versa. Those are scientific facts. So is evolution. Understanding the principles of evolution is critical to understanding a variety of environmental and medical phenomena.

Like many other scientific concepts throughout history, evolution has been challenged as heretical. Acceptance of evolution as a biological fact took awhile: Charles Darwin published his book "On the Origin of Species" a century and a half ago. But progress has been made. The book has a five-star rating on amazon.com.

Evolution is as real as gravity. If you want overwhelming evidence supporting evolutionary change in organisms, consider bacteria, which reside inside each of us. Bacteria have discernibly evolved in the last half-century. Remember penicillin, the wonder drug that extended millions of lives during and after World War II? Penicillin was medicine's weapon of mass destruction, stopping the pneumonia-causing streptococcus and other nasty bacteria dead in their tracks.

But guess what? When penicillin began to wipe out the bacteria we used to call "germs," the bacteria resorted to their secret weapon, one so secret it took years before we were aware of it. The bacterial arsenal--chromosomes and genes--was not the surprise. Scientists knew about that. What medical science did not know was how the arsenal was being deployed. That is, one in a billion or more bacteria had a gene (or acquired one through a process too complex to discuss here) that resulted in its being immune to penicillin.

Enter natural selection and evolution. A bacterium in someone's infected body part survived a penicillin dose. A single bacterium does not cause a problem, unless it reproduces. A surviving bacterium eventually becomes two, which become four, and so forth and so on. Of course it may take a few years for the bacteria to reach levels that could get a person's attention by causing an illness. In fact, before the medical profession was even aware of a change, the bacteria moved on to someone else's body or wherever bacteria spend their time. The first report that a strain of pneumonia-causing bacteria was resistant to penicillin appeared in 1967.

Meanwhile, bacteria were surviving penicillin all over the world. But all seemed quiet on both the Western and Eastern fronts because the bacteria had not risen to their full power. Now they have, and the effectiveness of penicillin has diminished. The important point is the process that occurred to create these strains of penicillin-resistant bacteria--evolution. The bacteria evolved. They changed. The streptococcus bacteria are not the same anymore genetically. They have been created anew, through the process of evolution.

Most educated people understand that the genetic makeup of every species on earth constantly changes as individuals die and others are born, and most of them understand that this is evolution. The controversy between some religious beliefs and the process of evolution revolves around what we humans were thousands or millions of years ago. The interpretation of evolution in the context of human origins is the central problem creationists have with the concept.

Whether we have changed genetically over the last few centuries in any perceptible and significant way I cannot say, but what our ancestors were doing and looked like in the misty past is intriguing to think about. How can anyone not think it is intriguing? Why should anyone feel threatened by scientists' examining the ancient origins of any species, including humans? Discovering what we were like genetically eons ago does not alter what we are today.

No one need be concerned about the study of evolution. We should, however, become apprehensive when any group of nonscientists begins telling teachers how to teach science. No good can come of that. Individuals who object to teaching evolution on religious grounds should ponder this question: Is your God powerful enough to have created a world in which organisms evolve? Mine is.

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