• Science: Evolving knowledge
Science: Evolving knowledge
St. Louis, Post-Dispatch, Tuesday, Oct.
Belief in evolutionary theory is a kind of faith, its critics argue. Like belief in God, it cannot be objectively proven.If one accepts that premise, then why shouldn’t schools teach “alternative theories” like “intelligent design”? That question is at the heart of challenges to evolution now playing out in a Pennsylvania courtroom, the Kansas Board of Education and state capitals across the country, including Jefferson City. But they are equivocation, a linguistic game based on popular misunderstanding of science. Evolution can – and has – been objectively tested in a variety of ways. One of the most recent confirmations can be read in the DNA of chimpanzees.
Last month, researchers announced they had mapped the exact order of all 3 million bits of chimp DNA. As Darwin would have predicted, it is remarkably similar to human DNA. But this new confirmation goes well beyond similarity.
Having already sequenced the genomes of mice, dogs, flies and humans, biologists developed a mathematical model to predict the range of harmful mutations in a particular animal’s genetic code. The formula is based on results of earlier sequencing work and population size. They put it to the test when chimp DNA was mapped. The results were as had been predicted.
That’s crucially important. The true test of the validity of a scientific theory is its ability to not only explain the past, but also “predict” future discoveries. By the middle of the 19th Century, for example, scientists had theorized that germs spread disease. That insight was the foundation of modern medicine. It came decades before sophisticated microscopes that could detect microbes.
In the same way, Darwin’s theory, advanced in the 19th Century, best explained evidence of species changes over time, even though Darwin himself had no idea precisely what caused the changes. New discoveries since then – such as the existence and structure of DNA – fit neatly into it. Darwin’s theory explains both well-established processes, such as antibiotic resistance caused by mutations in bacteria, and esoteric new discoveries, such as the number of harmful mutations in chimp DNA. Intelligent Design offers no such insights.
Religious fundamentalists in Pennsylvania, Kansas and the Missouri Legislature insist that schools teach the evolution “controversy.” In the name of free inquiry, they demand that students be exposed to alternative theories. The only controversy here is political, not scientific; that may well be taught in American history classes exploring the growth of religious fundamentalism in the late 20th and early 21st centuries.
But from the perspective of sound science, there is no alternative to teach. The only controversy is whether public school students should be taught religion or science in science class. That answer should be obvious.