Is It Only “Good” Science When It Confirms Your World View?
Evolutionary Psychology's Critics Still Don't Understand The Field
Posted Feb 12, 2013
Most people, when critical of some finding or some field, try to do things like keep their biases hidden, opting instead to try and argue from a position of perceived intellectual neutrality. Kate Clancy, evidently, is not most people. In her recent post at Scientific American, she lays it all out there, right in the title: “5 Ways to Make Progress in Evolutionary Psychology: Smash, Not Match, Stereotypes“. So, there you have it: if evolutionary psychology wants to progress as field, the practitioners ought to ensure we are getting results that Kate finds to be personally palatable so, rather than run experiments, we ought to just ask her what she likes instead. I can only imagine how much time and money this will save us all when it comes to collecting data and getting through the review boards, never mind all that pesky theory development. Of course, her suggestion for progression in the field might not be useful when it comes to developing and testing hypotheses about subjects that aren’t (heavily) stereotyped, but, in all fairness, her suggestion isn’t likely to be helpful in any case at all.
Round 1: [Evolutionary Psychologists] aren’t measuring what we think we are.
The point here is that evolutionary psychologists sometimes use proxy measures to measure other variables. So, for instance, if you want to study some theoretical construct like, say, “general intelligence”, you might use the results of some other test, like an IQ test, to draw inferences about the initial construct (people who score high on the IQ test have a lot of general intelligence). Now there’s nothing wrong with pointing out the fact that these proxy measures might not be tapping the underlying construct that you think they are, nor is it particularly problematic to point out that the underlying construct you think you’re measuring might not even exist. I’m fine with all that. Where I get lost is when I consider what any of it has to do with evolutionary psychology, specifically. Are evolutionary researchers worse at creating or using proxy measures? Does this point speak to the theoretical foundations of evolutionary psychology in any way? Since Kate provides no evidence to help answer the first question, I’ll assume that answer is probably a no (unless Kate is just stereotyping evolutionary researchers as poor in this department). Since proxy measures in no way at all speak to the theoretical commitments of the field itself, this entire point seems rather misguided. If she was talking about the field of psychology more generally, sure, this is a research pitfall to avoid; it’s just not one specific to my field. Round one goes to stereotype confirming evolutionary psychology.
Round 2: Undergrads only teach us about undergrads.
Kate’s criticism here comes in two parts: concerns for generalizability across samples and concerns that undergraduates can’t tell us anything useful about human psychology. Taking them in order, in psychology more generally there is a reliance on undergraduate samples, mainly because they’re cheap and convenient. The problem, though, is that the results of research on some of these undergraduates (typically those taking introductory to psychology, no less), might not tell us much about people who differ from them, either in age, race, education, nationality, social life, etc. On that account, Kate is indeed correct: there might or might not be problems in generalizing from handfuls of undergraduates to the human race more generally. Again, however, this criticism runs directly into the same hurdle her last one did: it’s not specific to any of the theoretical commitments of evolutionary psychology. The problem here is one faced by psychology more generally and, if anything, the people who tend to realize the importance of cross-cultural as well as cross-species research tend to be evolutionary people, at least in my experience.
Her second point, however, is even worse. Kate seems to go from undergraduates might not be able to tell us much about the human species to undergraduates definitely do not tell us anything useful, or, as she puts it, are “about as far removed from the conditions in which we evolved as you can get“. What Kate fails to recognize is that, in the vast majority of respects, these undergraduates are very similar to people everywhere else: they form relationships, both sexual and social, they discriminate between potential mates, they reason, they morally condemn others, they defend against moral condemnation, they eat, they sleep, they reciprocate, they punish non-reciprocation, they learn language, and so on. Focusing on a few superficial differences between groups of people can, it seems, make one miss the oceans of similarity between them. Just because undergraduates aren’t living as hunter-gatherers, it does not follow that they have nothing useful to tell us about human psychology. Round two also goes to stereotype confirming evolutionary psychology.
This charge is a classic one: there’s more to evolution than selection; there are also byproducts, drift, and mutation and those evolutionary psychologists need to recognize this! In Kate’s example, for instance, evolutionary psychologists might make up adaptive stories about her choice of sock color. If that was the state of evolutionary psychology, we truly would be a field in need of scolding. Now I could point out that, a little over two decades ago, in what might be considered the foundational text of the field, the byproduct, drift, and mutation issues are all discussed, and every major figure in the field has, at many points, explicitly acknowledged the role of these forces (see here, specifically charge 2) and leave it at that. I could also point out, as I have done before, that predictions derived from hypotheses of drift don’t tend to make very useful predictions. However, there are two additional points to not miss.
First, suggesting that psychological traits have adaptive functions is a step up from most non-evolutionary psychology, which tends to either posits useless functions (i.e. self-esteem or ego defense) or no functions at all. In this regard, evolutionary psychology is better, not worse, for it. Secondly, and more importantly, Kate gets a lot wrong in this section. Her initial point about how not all behaviors are the result of psychological adaptations misses the point entirely. Her behavior – choice of sock color, in this case – might not be the result of a specific module designed with the function of choosing sock color, but it would be a mistake to, from that, conclude it wasn’t result of other psychological adaptations. This would be as silly as my concluding that, because my body didn’t evolve to eat pop-tarts, my ability to digest them must not be a result of any physiological adaptations designed for digestion. On top of this misunderstanding, she then goes on to suggest that adaptations are heritable, by which she means some variation in them must be due to unique genetic factors. Under this logic, hands aren’t adaptations, because variation in having hands tends to not have a heritable genetic component (as well pretty much all do have hands). Anyone familiar with adaptationist logic will tell you pretty much the opposite: many adaptations – like livers and hands – tend to show very low heritability, because selection tends to remove heritability from the population. Round three is over, and it’s not looking so good for stereotype disconfirmation.
Round 4: There is more than one way [to reproduce]
This point suggests that, apparently, evolutionary psychologists have yet to realize that there’s more than one successful strategy that people can adopt when it comes to reproduction. We apparently don’t realize that there are many possible routes to take, and variable degrees of taking them. This is not only false; it’s stunningly false. In fact, in the next paragraph, Kate mentions that, sure, evolutionary psychologists have done research on some of these different, competing strategies, but it apparently wasn’t up to her standards. If she prefers a more nuanced view than the one she (likely incorrectly) perceives in the people doing research concerning whether one is more of a cad or a dad, she’s more than welcome to it. The researchers in the field would, if her view is better or has something they missed, happily accept the contribution. Were she to offer her view, however, my guess is that she’ll end up publicly disagreeing with an opinion that no serious researcher holds; basically what she is doing here. However, to imply, as she does, that evolutionary researchers don’t appreciate and attempt to understand variation, is just plain stupid, especially right after she points out that evolutionary psychologists already do it.
Kate then seems to try and say something about homosexuality, but, I admit, her point there is lost on me. It might be something along the lines of, “people who identify as non-straight sometimes have children, so there’s nothing to see here”, but I’ll admit that I’m having a hard time following what she’s trying to say, much less what the relevance would be. Round four, unsurprisingly, isn’t going to Kate.
Round 5: Just because [it's currently adaptive, that doesn't mean it previously was]
The only point I really want to make here is noting that Kate gets the definition of the environment of evolutionary adaptedness (EEA) dead wrong. As anyone familiar with this concept, or the primer on the subject, can tell you, the EEA is not a time or a place (much less on a savannah where everyone lived happily, as Kate seems to think it is), but the statistical aggregate of selective forces that shaped an adaptation. Thus, the EEA for language is different from the EEA for mate preference which is different still from the EEA for hands. I suppose I could also mention that every evolutionary psychologists knows that people do some things today – like wear heels and use hormonal birth control – that they used to not do during our evolutionary history, but, at this point, it seems to be so blindingly obvious to anyone that it hardly seems worth repeating. Final round goes to stereotype confirmation.
References: Tybur, J., Miller, G., & Gangestad, S. (2007). Testing the controversy: An empirical examination of adaptationists’ attitudes towards politics and science. Human Nature, 18 (4), 313-328