Author : Robert Sprackland
Evolution is a subject about which many people have firm opinions, whether based on facts, hype, or poor resource materials. As a starting point for this book, I shall present a set of "FAQs" or "Frequently Asked Questions." Brief answers follow, with the reader being directed to other chapters for more detailed explanations.Q. Despite all the publicity about biological evolution, isn't evolution just a theory with no more evidence for its support than other origin theories?A. Definitely not. The theory of biological evolution has received support from over a century of intense research. The features that make biological evolution a scientific theory include strong support from the fields of biology, geology, chemistry, physics and even cosmology. In essence, it is arguably the best-supported theory in science, with evidence coming from every major branch of science.Furthermore, in science the term "theory" has a very specific meaning. A theory is an idea substantiated by an assortment of evidence, and that has not been invalidated after significant testing. Perhaps it is time for scientists to use a new term to replace "theory," because "theory" has such a commonly accepted definition that is virtually the polar opposite of what a scientist means by the term. Evolutionary biology's "Old Man" (the late Harvard Professor Ernst Mayr) has recently substituted the term "fact" for "theory" in his latest book (Mayr, 2001). Calling biological evolution a fact is one succinct way to stop the verbal confusion.Q. Isn't most evidence for biological evolution intangible, mainly like mathematical explanations rather than real or observable evidence?A. Almost every aspect of modern medicine, genetic engineering, insecticide and pesticide development, and agricultural sustainability exploits real evolutionary data. The very idea of descent with modification came from observing closely related species and, more recently, living with fossil specimens. From the 1970s onward, direct comparisons of protein and DNA sequences have strongly bolstered both observed and mathematical models of evolutionary theory. Finally, despite strong claims to the contrary by "creationists," many cases of evolution have been and are being observed today. Examples will be given throughout this text.Q. But how can evolutionary science be considered so accepted when we frequently hear about dissention and arguments by evolutionary scientists? Isn't there a secret cadre of biologists who actually refute the theory?A. Emphatically no. Biologists almost universally accept the fact that evolution is a real, ongoing process. The infighting often presented in the press is not about if evolution occurs, but about how it occurs. The biggest philosophical divide is a question of whether a) genes are an organism's way of making new organisms or b) organisms are a gene's way of making new genes! Sadly, with careers and ego at stake, some of the scientists involved, as well as their supporters/detractors, sometimes resort to name-calling and rather unpleasant written and verbal attacks on each other. In no way, though, do these people doubt the reality of evolution. (See Morris, 2001, for a review of the different schools of evolutionary thought.)As for the very few biologists who doubt evolution's reality, they are far from secretive and retiring: indeed, they are making noises far greater than their number would suggest possible. It is unfortunate that these scientists, especially the relatively few who are actually trained in and practicing biology, make the huge error of proposing that any biological function that awes/confounds/mystifies them must therefore be evidence of a God. This is, modestly, a leap of faith completely unworthy of a scientist while in the practice of science.Q. Every two or three years I read about another state that wants to ban teaching of evolution, and school boards that forbid teachers to present evolution in their classes. Certainly there must be some validation for these actions.A. There is no scientific validation for these actions. So far, each case of repression has eventually been determined by courts to be attempts to replace science education with religious proselytizing. The National Academy of Sciences has even published a short and definitive statement explaining the Creationism is religion, not science. The major courts of the land have so far upheld this distinction. The result is that such religion-based actions by states or local school board to prohibit the teaching of evolution (or including "creation science" as part of the science curriculum) are eventually overturned. It is for precisely this reason that the religious zealots are trying to clothe their case as Creation "science," hoping that a gullible public will believe that a name change makes all the difference.Remember that legislatures, courts and school boards rarely have scientists as part of their makeup, and decisions are often based on popular—or perceived popular—conceptions of what the public wants. However, science, truth, and other values are not based on popularity polls, but on testable or observable evidence. People frequently try to forget complicated or unpleasant events and discoveries. Consider how many of us would like to deny that Adolph Hitler ever lived: alas, no legislation or opinion poll can erase his reality or his ghastly legacy. Hitler lived and that is a truth. Similarly, many people would like to forget the terrible end that came to the space shuttle Challenger that fateful day in January 1986. But from that disaster NASA learned many useful and important lessons so that the United States now continues with a very active and important space shuttle program.In short, truth may not always be pretty. Many people, including me, see evolution as a beautiful and wondrous explanation for life's variety, while other will always be disgusted by the implicit, though distant, kinship with apes, fishes, and slime molds. Truth, however, is not subject to opinion, fad or favor. Despite any negative legislation, evolution will remain a fact regardless of court orders or religious wishful thinking.Q. But if evolution is true, and if humans did evolve from apes, why are there still apes? Shouldn't they all have become humans?A. This is a persistent question that is simply a reflection of not understanding lineages. For example, if I have a daughter who marries a Mr. Smith, does that mean all the living Spracklands from which she came must either drop dead or also become Smiths? Just as one daughter (representing a single lineage) can in turn become and hence produce little Smiths, my hypothetical son will continue to be a Sprackland, and his male children will be and remain Spracklands.In biological evolution, the same idea is at work. One group of apes gave rise to a lineage that would (through many steps over millions of years) become humans. The offspring of the other young apes would continue to produce only apes. In time, some of those descendant apes might produce new species of apes, but the human/ape lineages would have long since diverged and will not cross again.Followed to its "logical" end, the Creationist idea that the presence of humans should mitigate against any living apes would ultimately mean that only humans should be present on earth. After all, evolution claims that all living things spring—if we look back far enough—from a common ancestor. If each new species could only exist if the parental species died out, then there would be no life today, for we could not live in a world without plants, bacteria, and other animals!My high school Latin teacher, Mr. David A. Elms, used to remind his classes daily that "you can lead a fool to knowledge, but you can't make him think." Despite centuries of intense educational efforts, many people in our society remain, by choice, ignorant of a great many things. Ergo, just because something is true or known doesn't mean all people will all rise above base ignorance. There are still apes and there are still willfully uneducated people, yet the rest of us still survive.
Keyword : Evolution, education, biology
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