ALICE EAGLY: The evolution of sex differences is a hot topic these days in psychology. The evolutionary psychologists promote a theory that there are, in fact, important inborn sex differences that arise from evolution. I have been promoting a different way of thinking about the characteristics, the psychological characteristics of men and women. In this theory, the most important influence is the roles that men and women have. To the extent those roles are different that men and women are differently distributed into roles in the society, they would develop a different psychology because they need a psychology that goes along with their life tasks.
So for instance, if women have the responsibility of caring for young children and men don't in a society, then women would need to be nurturant regardless of whether that was inborn, because the children have to survive. And if men, for instance, do warfare, then they have to develop more aggressive characteristics that would make them warriors or soldiers. And if women don't do that, they're not needed in that way. So in our theory, the roles are the main determinant of the psychology of men and women.
So then the question is, well, yes, but how did men and women get into different roles? Maybe it's an inborn psychology so that they might seek different roles. I think the answer is more complicated than that. And in the theory that I've developed with Wendy Wood, we have an aspect of this role theory that we call the biosocial origin theory.
And in that theory, the most important, evolved dispositions are physical characteristics. So men are bigger and stronger, particularly in upper body strength, and women have reproductive activity that men don't, obviously. Women gestate and then lactate. And in earlier cultures, that lactation could go on for a couple of years easily.
And so women have tasks, then, which tend to put them, therefore, in different roles because of those biological characteristics, not that automatically set a psychology, but they set life tasks that would differ between societies, depending on the kind of environment that society is. It may or may not be a society that has a lot of warfare. It may or may not have high birth rates.
And so it may or may not make much out of male strength in terms of high prestige roles. So the environment, then, would interact with those biological characteristics and produce a division of labor, as all societies have some division of labor. So in our theory, that's what's critical. It's the kinds of work that men and women do in a society for which they have a psychology that would come about in order to fit them to the roles.
And that psychology is kind of captured around the notion of gender roles by many gender theorists, including myself, that there are expectations about women and men that exist in societies that they then learn, and they internalize them, to some extent, and that those would then tend to regulate male and female behavior so that the behavior would be role appropriate.
As societies change and that role structure changes, then the psychology of men and women would change. We've seen that quite dramatically in the United States in the past 50 years, approximately, where the great majority of women now have become employed outside the home. And so women need a new psychology. They don't any longer have the psychology merely of being nurturers. But they need a workplace psychology as well, and particularly as women move into more powerful roles, they need a psychology by which they can be effectively leaders and effectively dominant in various ways.
So we see a tendency for women to have taken on many qualities that you might call masculine, like assertiveness and independence. And so we see some convergence in sex differences over time because women are in new roles. They haven't abandoned the child rearing part. They still do the main part of it. So we don't see in psychological data that they've become, in a sense, less feminine or less warm and caring. We don't see shifts there, I think because women are still doing a lot more child rearing than men, a lot more caring tasks.
But they've also taken on all of these workplace tasks, including moving into roles with considerable responsibility and prestige. So women tend to have a new psychology. So this is one of the kinds of evidence that would support the notion that the roles of men and women are the key to their psychology.