Evolutionary psychology: You’re doing it wrong (but you could do it better!)

The Descent Of Man Well, it didn’t quite happen like that. Photo by Minette Layne.

Over at Scientific American, Kate Clancy sums up the scientific case against evolutionary psychology:

[Evolutionary psychology] is trying to take on an incredibly challenging task: understand what of human behavior is adaptive and why. We can better circumvent the conditions that lead to violence, war, and hatred if we know as much as we can about why we are the way we are. What motivates us, excites us, angers us, and how can evolutionary theory help us understand it all?

Because of this, there are consequences to a bad evolutionary psychology interpretation of the world. The biggest problem, to my mind, is that so often the conclusions of the bad sort of evolutionary psychology match the stereotypes and cultural expectations we already hold about the world: more feminine women are more beautiful, more masculine men more handsome; appearance is important to men while wealth is important to women; women are prone to flighty changes in political and partner preference depending on the phase of their menstrual cycles.

It may not always be evident, but biologists who get all shirty when we see the latest evo-psych study splashed across the headlines generally agree with the most basic premise of EP: that humans are evolved, biological organisms, and that our present behavior is a result of our evolutionary history. What drives us up the wall is the refusal of EP research to apply understanding developed over decades of work by evolutionary biologists—the discovery that there’s more to evolution than natural selection, that natural selection often acts on many traits simultaneously, and that there may be many ways to acheive the same level of reproductive success.

With modern genetic tools and a modern evolutionary perspective, biologists—including Kate, who studies human reproductive biology in an evolutionary context—have learned a lot about how natural selection and other evolutionary processes shaped current human diversity. Some of the best examples so far are in relation to diet (drinking milk and cultivating corn) and adaptation to low-oxygen conditions at high altitude; but there’s no reason the same methods can’t tackle other features of human nature, given sufficient quantities of the right data. Yet we rarely see EP studies based on the kind of data that could actually provide answers to the questions they ask. (And then, all too often, we see EP studies that are unmoored from basic biology altogether.)

So: The complaint that most evolutionary biologists have with EP isn’t that it’s asking the wrong questions, or asking questions it has no right to ask. It’s that EP is using the wrong tools to answer those questions. And, to the extent that we agree that those questions are important, it’s upsetting to see someone claim to have answered them using only surveys of undergraduates. We’re like plumbers expressing our exasperation with a guy who insists on intalling a new toilet using a nail file and a hot glue gun: dude, go buy a wrench!

Anyway, enough from me. Go read Kate’s post already.◼