Working backwards through our four reasons to ignore evolution, we have shown that smart people don't necessary converge on the facts of the matter from different starting positions (4) and that reasoning on the basis of design benefits from knowledge about the designing process (3). Here is our next reason for ignoring the E-word (2):
A reasonable research strategy is to study what is, without worrying much about how it got that way. After all, something like the brain is available to be studied in minute detail, whereas how it got that way is more speculative. Why speculate when we can study the real thing?
This statement can be true in a limited sense. All of Tinbergen's questions can be studied independently, including questions about proximate mechanisms. Insofar as science involves division of labor, individual scientists can spend their entire careers studying proximate mechanisms without thinking about the other three questions.
Yet, what's sufficient for a specialist can be woefully inadequate for a field as a whole. In the course of writing these posts, I have been emailing my colleagues for their thoughts. Herb Gintis offered this observation: "Some researchers only care about proximate mechanisms. They don't care about 'why' but rather about 'how'. This is why a molecular biologist could be a creationist, for instance."
Herb's example of a creationist molecular biologist perfectly illustrates how a reason for ignoring evolution can suffice for a small minority of individuals but fail miserably for a field as a whole. If all molecular biologists were creationists, that would be a disaster. If all biologists were creationists, that would be more disastrous still. Yet, the issue before us is whether entire human-related subjects such as psychology, economics, or education, need to be approached from an evolutionary perspective. The argument that everyone can restrict themselves to proximate mechanisms fails as miserably for these broad fields of inquiry as for molecular biology and biology as a whole.
Moreover, the study of proximate mechanisms is always founded upon a set of assumptions about function or lack of function. The only reason that a creationist can function as a biologist is if the function (or lack of function) of the particular mechanism being studied has been correctly inferred. You can't ask "how" questions unless you are in the ballpark of the right "why" question.
To illustrate this point with a biological example, some bird species are genetically adapted to migrate south during the winter. The proximate mechanisms that enable them to do this include the ability to memorize the night sky as nestlings. Other bird species are genetically adapted to overwinter in cold climates. The proximate mechanisms that enable them to do this include the ability to memorize hundreds of locations where food has been stored. Imagine that I give you a bird species to study without telling you anything about its ecology or migratory habits. How many decades would it take you to discover its particular adaptations, just by studying its brain? This is why asking "how" and "why" questions in conjunction with each other, along with phylogenic and developmental questions, is so essential for evolutionary biology as a whole--and just as essential for human-related subjects.
The human-related disciplines abound with examples of "how" questions founded upon the wrong "why" questions. Consider an article titled "Why do humans reason? Arguments for an argumentative theory", by Hugo Mercier and Dan Sperber, published this year in the journal Behavioral and Brain Sciences. I cannot improve upon their language:
How do humans reason? Why do they reason? These two questions are mutually relevant, since the mechanisms for reasoning should be adjusted to its function. While the how-question has been systematically investigated...there is very little discussion of the why-question. How come? It may be that the function of reasoning is considered too obvious to deserve much attention. According to a long philosophical tradition, reasoning is what enables the human mind to go beyond mere perception, habit, and instinct.
Mercier and Sperber propose that human reasoning abilities evolved largely for the purpose of producing and evaluating arguments in communication. This provisional answer to the why-question makes sense of empirically documented phenomena that appear anomalous and paradoxical against the background of different answers to the why-question that have guided philosophical inquiry on reasoning for centuries and scientific research for decades. The lively open peer commentary that follows their target article reinforces the main point of this post--you can't ask a good "how" question if you're not asking the right "why" question. And you can't ask the right "why" question without seriously consulting evolutionary theory.