It's amazing how divided opinions are about evolutionary psychology.    Some very fine philosophers and cognitive  scientists are  really big fans of  the genre.    Other equally fine philosophers and cognitive scientists appear to  see little of merit in it.   The philosopher of biology John Dupre, who was a guest on our show a few weeks back talking about genetic determinism, says the following about the  evolutionary psychology of sex and gender:

... [it]  offers us mainly simplifications and banalities about human behavior with little convincing illumination of how they came to be banal. It offers no account of the great differences in behavior across cultures, which is exactly what we want to know if we were interested in exercising any measure of of control over changes in these phenomena.  It offers no account of why different people develop such diverse sexual proclivities (notoriously, it has nothing to but the most absurd evolutionary fantasies to offer in explanation of homosexuality).  And it offers no account of how complex motivations underlying sexual behavior interact with the pursuit of many other goals that inform the lives of most humans.  In fact it offers us nothing, unless perhaps a spurious sense of the immutability of the behaviours that happen to characterize our own contemporary societies.  This is scarcely the revolution in our undertanding of human behaviorus so enthusiastically advertized by the exponents and camp-followers of evolutionary psychology.

Though Dupre is perhaps more extreme than many others,  he certainly isn't  alone in heaping at least some degree of  scorn on evolutionary psychology.  But  I don't think evolutionary psychology is nearly as bad off as its worst critics think.

Some criticisms of evolutionary psychology aren't really criticisms of the research program itself, but are really criticisms of the misappropriation  of the results of evolutionary psychology. For example, some people, especially on the political right, think that biology determines appropriate gender roles in some direct and inflexible way.  They probably don't think this directly because of evolutionary psychology, but someone with a merely passing acquaintance with the results of evolutionary psychology  might think that those results somehow justify such a view.   But nothing in evolutionary psychology suggest that biology directly and inflexibly determines gender roles.  Certainly nothing in evolutionary psychology suggests anything about what the distribution of gender roles ought to be in twenty-first century cultures.

Some  people of a leftist bent tend to think, on the other hand, that gender is socially constructed "all the way down.'"  Sometimes such people seem to think that  culture  floats free of biology.    Evolutionary psychology does suggest that this view of biology and culture as really two distinct things,  related in only minimally constraining ways,  can't be sustained.   And here I think the evolutionary psychologists actually get much the better of the argument than  their critics do.

I'll use the example of  gender roles to illustrate what I mean.  Think about it this way. There is a massive three way gender-coordination problem faced by ours and any other species that reproduces sexually. Males have to coordinate with males, so that they don't kill each other over the potential female partners. Females have to coordinate with females so that they don't kill each other over potential male partners. And females and males have to coordinate with each other so that mate selection strategies and preferences are convergent rather than divergent.

There are certainly  lots of solutions to the set of coordination problems that sexually reproducing species face.  Some of them  are probably not very cognitively or computationally  "demanding" to use not quite the right word. But in creatures like us who have the capacity for a complex form of social life, who remain immature and dependent on parental support for a comparatively long period of our lives, any "solution" to the three way coordination problem is going to be massively tied up with all sorts of social structures, including facts about the distinctive biological structure of a characteristically human reproductive life.  I mean by that that we spend a comparatively long time as prepubescent youth, during which we have a whole  lot of socialization and cultural knowledge to acquire.

Now even if you think, as I do, that both our capacity for a distinctive form of social life and the general  structure of an individual human life are the result of some sort of evolutionary process, it certainly doesn't follow that evolution gave us a single solution to the three way coordination problem in the sense of giving us a fixed set of gender roles once and for all. But it wouldn't be  surprising, it seems to me,   if it turned out that evolution supplied us with cognitive and emotive make ups that in some way more or less tightly constrain the possible solutions to the three way coordination problems. How tightly? I can't say. But obviously not so tightly that gender roles are fixed across cultures. I suspect that not so loosely that just anything goes. Right now that's just a hunch in need of evidence and argument.

It's not as though there is currently no evidence, however.  Eleanor Macoby's work, for example, on the structure of children's playgroups and the dynamics of gender socialization, suggests, to me at least, that there probably are some evolutionary constraints on the distribution of gender roles.   It turns out, for example, that all around the world, in pretty much all human cultures,  there exists what we might call a division of gender roles among the sexes.   Moreover, it starts pretty early and it looks as though the children themselves have the primary role in bringing about the division of gender roles.   What I mean by this is that from about the time they enter preschool or some other setting in which they first come into contact with many other children of  their own age,  children start segregating themselves into boy and girl playgroups.  Girl play groups have distinctive styles of play from boy play groups.  Girls, by and large,  prefer to play in girl playgroups and boys prefer to play in boy play groups.   This happens even despite the best efforts of teachers and other adults to promote gender integration.  Moreover,   girls and boys "police" gender roles differently.  Girls are evidently more tolerant than boys are of boys who want to enter girl playgroups and of  girls who want to enter boy playgroups.  Boys, on the other hand, are much more severe gender police.  Certainly  styles of play, for both girls and boys,  vary from culture to culture.  But the apparent high level regularity, at least as I understand the work,  is that in many cultures boys and girls will segregate themselves in this way. 

I don't want to make too much of this kind of thing right now.   I certainly don't think there is any normative claim to be made on the basis of this kind of thing about what the appropriate division of gender roles should be.   But I do think that by trying to think in both "social dynamic" terms about our three way coordination problem and in evolutionary terms about what, if any thing, natural selection has to teach us about what,  if anything, constrains the solutions to the gender coordination problems that really possible social/cultural orders can "settle" into, is very much worth doing. Certainly history and culture and the distribution of power are sources of constraint, but probably some constraints derive from evolutionarily instilled facts about the very general structure of male/female cognitive/affective make ups.

One really deep problem with this sort of approach  is that  we cannot  easily separate  out the contributions of the various constraining factors.  But that doesn't mean that it isn't worth trying to figure out what the various constraints are, how tightly they constrain, and why there are just those constraining factors rather than some others.   Of course,  we need empirical (and other) methods and some real data if we are to make headway on these questions.  And one may worry that we have neither the data nor the methods.     There is, I think, something to this worry.  In part, that is because  we have completed only part of  only one actual walk through the space of cultural possibilities.  We don't know in advance how large that space really is or how "quirky"  and ad hoc our own walk through that possibility space has been. 

If we could more freely employ the method of hypothesis testing and generation, we would certainly be a lot better off.  Since history provides us with some alternative arrangements and  since social experimentation -- especially in an age like ours -- happens relatively constantly, it is not as though we have no clue about the space of possibilities.  But it's admittedly hard to separate out the contributions of the different possible constraining sources when you can't freely manipulate the data and experiment to your heart's content.  Not to say it's hopeless. Just hard.

In spite of these limitatins,  I guess I still think that one of the really cool things about  evolutionary psychology is that it is pretty much a brand new style of hypothesis generator for some really hard problems.    I think people underestimate the importance of simply having  a new source of hypotheses on the table.    It's that underestimation that leads many to curtly dismiss as yet unconfirmed evolutionary hypotheses as so many "just so" stories.   

Admittedly, we're currently at a stage of inquiry in which generating evolutionary hypotheses  is a lot easier than testing and confirming them.  Partly because natural selection is mostly a thing of the past and because there isn't a fossil record of hominid cognitive architectures, testing evolutionary  hypotheses about the structure of the mind is bound to be a REALLY HARD THING. That I  readily admit.  I'm not even  completely sure it can be done. 

Since testing evolutionary hypotheses is relatively hard, and generating them is relatively  easy,  one might be tempted to  think that we should just set such hypotheses to one side as more trouble than the are theoretically worth. That  would be a mistake. What really is required is just a little modesty -- well, maybe a lot of modesty --  about what you can and can't actually establish at this stage in the history of inquiry. 

Of course, culture formation doesn't always wait on scientific progress. So we will go on trying to construct our culture, even if science can't tell us anything terribly deep about the possibility space we are walking through or the constraint we will bump up against,  in the attempt.  But that happens all the time. Unfortunately, lots of time when science "catches up" it turns out that we  attempting to construct a culture on a foundation that wouldn't support it. But we're pretty good at living for generation in castles built on sand.