The Fact of Evolution: Implications for Science Education

Abstract

Creationists who object to evolution in the science curriculum of public schoolsoften cite Jonathan Well's book Icons of Evolution in their support (Wells2000). In the third chapter of his book Wells claims that neither paleontologicalnor molecular evidence supports the thesis that the history of life is an evolutionaryprocess of descent from preexisting ancestors. We argue that Wells inappropriatelyrelies upon ambiguities inherent in the term `Darwinian' and the phrase `Darwin'stheory'. Furthermore, he does not accurately distinguish between the overwhelmingevidence that supports the thesis of common descent and controversies that pertainto causal mechanisms such as natural selection. We also argue that Wells' attemptsto undermine the evidence in support of common descent are flawed and hischaracterization of the relevant data is misleading. In particular, his assessment ofthe `Cambrian explosion' does not do justice to the fossil record. Nor do his selectivereferences to debate about molecular and paleontological phylogenies constitute a caseagainst common descent. We conclude that the fossil and molecular evidence is morethan sufficient to warrant science educators to present common descent as a well-established scientific fact. We also argue that diagrams depicting the `tree of life' can be pedagogically useful as simplified representations of the history of life.