"Our brains are fluid and plastic"

For some reason, it’s “bash evolutionary psychology” week. First, Sharon Begley writes a 7-page essay in Newsweek, “Don’t Blame the Caveman.”, and now David Brooks gamely takes on the subject in the New York Times: “Human Nature Today”.

Brooks’ target is Geoffrey Miller’s new book, Spent: Sex, Evolution, and Consumer Behavior. I haven’t seen Miller’s book yet, maybe they’ll send me one. I have a feeling there’s more to it than Brooks’ two-paragraph synopsis.

We are all narcissists, Miller asserts. We spend much of our lives trying to broadcast our excellence in these traits in order to attract mates. Even if were not naturally smart or outgoing, we buy products and brands that give the impression we are.

It seems to me that an evolutionary analysis of consumer behavior is a tall order. You have to account for the fact that nature didn’t set up the mall; a lot of clever advertising people did. Just as David Kessler pointed out for restaurants, stores are busy trying to exploit innate biases toward products and to manipulate learned responses to them. Some of it is a novel environment, other parts are fairly old applications of information foraging. The combinations of old and new, cultural variations, and varying levels of group participation may make cooking a better analogy than foraging.

Putting the intrinsic challenge aside, I think David Brooks shoots wide of the mark. He lists a catalog of alleged excesses in Miller’s book, and tries to pivot into the point that evolutionary psychology in general is overreaching in its interpretations of human behavior. These “criticisms” of evolutionary psychology are hardly new. Some of them may have some force yet, but in Brooks’ hands they hardly slap harder than Ann Landers’ famous “wet noodle”:

But individuals arent formed before they enter society. Individuals are created by social interaction. Our identities are formed by the particular rhythms of maternal attunement, by the shared webs of ideas, symbols and actions that vibrate through us second by second. Shopping isnt merely a way to broadcast permanent, inborn traits. For some people, its also an activity of trying things on in the never-ending process of creating and discovering who they are.

So what? Many kinds of sexual and status displays in nature are highly learned – bowerbirds construct displays from physical objects, many songbirds learn songs based on features of the songs they hear. They’re all trying to create and discover (which is highfalutin’ way to say, learn) what to do. That doesn’t mean that the behaviors don’t evolve under selection – it just means that an evolutionary account of the behaviors must explain the learning mechanism.

In humans, there’s no question that status displays are part of mating and social competition. The outcomes of mating and social competition influence fitness. What remains unknown is the extent to which learning may be influenced by innate biases. How do we choose who to copy? Why do we respond to some signals (nowadays, products) and not others? Is familiarity enough – old-fashioned, blank-slate type learning? How much do developing minds depend on cues other than repetition?

Nobody really knows the answers to these questions, at least not well enough to persuasively test hypotheses about the evolution of human minds. But Brooks implies that such questions aren’t worth asking. He thinks that it’s enough to claim that humans aren’t “hard-wired” – as if that (false) dichotomy actually conveys any information. In doing so, Brooks confuses the currency of evolution (that would be, fitness) with the currency of individual fulfillment. They’re not the same, and in many cases they work against each other.