Editorial - May 2009 - Volume 109 (5)

Teaching the Pros and Cons of Evolution in the 21st Century

Joel Kirschbaum, Guest Editorial

The ability of administrators and policymakers to discourage public school science teachers from presenting the objective evidence for evolution is continuing. We all know that the past barring of the theory of evolution from the classroom is now illegal. But then the idea of “intelligent design” was introduced as an alternative theory. This scientifically discredited theory of the origin of life was examined in court and now cannot be legally taught in most public schools. However, believers in biblical creation want educational “balance” by asking teachers to include either the controversies or the weaknesses of evolution when its strengths are taught. This editorial emphasizes 21st century data supporting evolution and also presents the scientific “cons” to the theory. Current evidence is essential because many believers in the special creation of life on Earth impose artificial interpretations on older archeological, embryological, and anatomical evidence for evolution. For example, they consider dinosaur bones to be merely a few thousand years old and to be the by-products of Noah's flood. To biblical fundamentalists, fossils must be forced to follow faith, not facts.

The major anti-evolution arguments involve the origin of complex molecules and cells. However, experiments have shown that many simple bio-chemicals can be synthesized using the likely atmosphere and catalysts thought to exist on an early Earth. Still to be replicated in the laboratory is the formation of macromolecules like DNA, RNA, and proteins from these simple precursors. In addition, evolutionary scientists need to produce the mechanisms of how DNA and RNA evolved reproduction, and came to be packaged in cells. Also unknown is how cells evolved reproducible replication, assembly, specialization, and, of great importance; how one or more cells can send signals or messages to other cells, which then respond. These are all questions about what happened at the beginnings of life. This problem is shared by astrophysicists who are questioned both about what existed before the “big bang”, and what happened just afterwards.

Before considering the modern evidence for evolution, we must mention that radioactivity, the basis of both nuclear weapons and some medical treatments, proves conclusively that the Earth is old enough for evolution to occur. The decay of a chain of both short- and extremely long-lived isotopes (as measured using equipment like mass spectrometers which are familiar to viewers of true-crime TV programs) shows the Earth to be about five billion years old. These eons of existence show that there was sufficient time for humans to evolve.

The probability of life occurring is analogous to the frequency of one golfer hitting two holes-in-one in one week. The reason that this rare event can happen is that millions of golfers daily are playing 18 holes worth of balls. Similarly, there were many chances for life to originate because there are about a hundred billion suns in our galaxy and billions of galaxies in a universe dated to be about 14.7 billion years old. About 30% of observed suns have planets, as shown by side-to-side solar wobbles due to the pull of gravity on the sun by an orbiting planet. So life on our planet is a rare but not statistically impossible event!

The all-important, overwhelming argument for evolution is DNA. This molecule, and its related cousin RNA, provide the genetic links all life lies along, as well as the means of mutation and the mechanism for evolution to occur. It also provides a tool for identifying the degree of relatedness of all biological organisms that have ever lived, including humans. For example, consider the situation where DNA is found at a crime scene. All humans have 99.9% similar DNA but different individual's DNA can be distinguished from each other. The police get DNA samples to compare with those that are identical to DNA already on file from a felon. They also obtain DNA from family members in order to eliminate or identify them as possible suspects. Every criminal cold case solved is another point proving evolution. So far, DNA evidence has freed from death row more than 40 prisoners who were wrongly sentenced to be executed. Incidentally, a well-known governor recently signed a bill increasing funding for DNA studies in state criminology labs but, paradoxically and illogically, the governor publicly rejects evolution.

Evolution doesn't propose that monkeys are our great grandparents - only that we have common ancestors. DNA studies show that the further removed in lineage one creature is from another, the more dissimilar is the DNA. The primate, who has 98.5% of its DNA in common with humans, is eating a banana that is about 25% related to human DNA. Indeed, there are no controversies about evolution among objective thinkers. For example, the false demand to produce “intermediate species” was easily dismissed because no present-day species is the ancestor of any other. We also now understand the evolution of such complex structures as the skull, eye and the three-bone cochlear apparatus, as well as the interrelatedness of the molecules involved in blood-clotting. The continuous expansion of our understanding of these and other biological structures provides mounting evidence that evolution is a sound theory that all students should learn.