Although scientists view evolution as an indisputable feature of the natural world, most Americans simply do not believe that it occurs, or they reject naturalistic explanations for biotic change. Empirical studies have revealed that students and teachers often know quite a bit about evolution but still do not accept it. This somewhat counterintuitive finding has been empirically corroborated and has led science educators to investigate this pattern in order to provide suggestions for effective evolution instruction (e.g., Rosengren et al. 2012). Within the lucid, compact, up-to-date, and highly readable pages of The Evidence for Evolution, author Alan R. Rogers takes an approach that most science educators have found inadequate: exclusively using logic, parsimony, and the force of evidence to precipitate conceptual change about evolutionary belief. Reactions from both supportive and dissenting readers to this nicely written text will depend on how much faith they place in the use of logic to challenge the worldviews of intelligent-design creationists.
Two premises appear to frame this short book: Biology courses and textbooks are focused on evolutionary mechanisms at the expense of the evidence for evolution, which most people are not aware of, and once disbelievers of evolution are exposed to the massive amount of evidence that exists, they will change their beliefs. I am not sure whether most biologists would agree with the first premise, given the increasingly elaborate coverage of evolution in textbooks. Indeed, having reviewed some of the bestselling introductory biology books (Nehm et al. 2009), I know that many topics that Rogers discusses are, in fact, covered in these texts. I am also doubtful as to whether science educators would agree with the second premise: Empirical studies have shown that learning more about evolution often fails to precipitate a meaningful belief change.
Within the 10 chapters that form the structure of The Evidence for Evolution, the choice of topics is excellent. Also noteworthy are the use of fresh empirical examples, the integration of phylogenetic trees, and the inclusion of paleontological patterns, radiometric dating, and genomic data. The evidence for evolution is vast, and choosing appropriate examples for a short book is no small task.
Writing about evolution can be quite challenging, given that many students and teachers view teleological factors as sufficient explanations for evolutionary change. It is important, therefore, to clarify what we mean when we use such language (Rector et al. 2012). At times, Rogers uses intentional or teleological language: “Every living thing must solve many engineering problems just to stay alive” (p. 34). Although biologists will understand what Rogers means, the same may not be true of novice readers. Individual organisms cannot willfully change the traits that they have (e.g., they cannot intentionally modify a phenotypic feature).
Language may also invoke ideas that are at odds with current scientific thinking, and although Rogers writes with precision and clarity, some exceptions are worth mentioning. Trait loss, for example, has been shown to be a particularly difficult concept for students and teachers to understand (Nehm and Ha 2011). When describing the loss of whale limbs (“Over the next few million years, whales relied less and less on their legs,” p. 20, or “Hind limbs dwindled,” p. 22), his language may be in greater alignment with common misconceptions about use and disuse than with natural selection. When writing about evolution, scientists need to be more cognizant of readers' potential interpretations of the language that we use.
One literary device employed throughout the text is the contrast of supernatural explanations (e.g., “Perhaps we sprang from the hand of God,” p. 81) with naturalistic, evolutionary explanations. Although this approach makes the text engaging, it makes little sense from my perspective and has the potential to exacerbate readers' existing confusions about core ideas relating to the nature of science (NOS). Most students and teachers remain unaware of the ontological presuppositions that undergird the scientific process (e.g., methodological naturalism). By definition (e.g., from the National Academy of Sciences), science cannot speak to or evaluate the relative merits of supernatural explanations; no amount of evidence will ever be able to tip the scale in favor of a naturalistic explanation relative to a supernatural one or vice versa. It is not clear why Rogers takes this approach.
Students' and teachers' evolutionary acceptance levels are known to be related to their understanding of the NOS. Because many Americans are deeply confused about NOS concepts such as observation, inference, testability, theory, law, model, proof, experiment, and hypothesis (Lederman 2007), addressing NOS misconceptions has become de rigueur in evolution education. I was surprised, therefore, to find that The Evidence for Evolution does not discuss what evidence is or how the term is used in evolutionary science. More problematic is the somewhat careless use of NOS terms (e.g., “this experiment proved that,” p. 12, emphasis added, and “we can also see new species forming” p. 16, emphasis added). In order to prevent the reinforcement of such NOS misconceptions (e.g., that scientific knowledge is certain because it is proven; or the conflation of observation and inference), the meanings of everyday and scientific terms must be carefully distinguished for readers.
To make the most of Rogers's important contribution, pairing The Evidence for Evolution with a textbook about the NOS (e.g., Espinoza 2012) is much more likely to achieve what the author admirably aspires to: an understanding, acceptance, and appreciation of evolutionary science. Facts, logic, and parsimony are unlikely, on their own, to affect most people's perceptions of the plausibility of evolution.