The patterns of variation and change help us understand how gender inequality works. Systemic inequality doesn't just happen. People (in the aggregate) get up in the morning and do it every day. To understand how it works, we need to see how it varies (for example, some people resist equality and some people dedicate their lives to it). Someone who studies inequality but doesn't care about change and variation is not a social scientist.

Patriarchy

"It's easy to find references to patriarchs, patriarchy or patriarchal attitudes in reporting on other countries," writes Nancy Folbre:

Yet these terms seem largely absent from discussions of current economic and political debates in the United States. Perhaps they are no longer applicable. Or perhaps we mistakenly assume their irrelevance.

In fact—my interpretation of the facts—the United States, like every society in the world, remains a patriarchy: they are ruled by men. That is not just because every country (except Rwanda) has a majority-male national parliament, and it is despite the handful of countries with women heads of state. It is a systemic characteristic that combines dynamics at the level of the family, the economy, the culture and the political arena.

Top political and economic leaders are the low-hanging fruit of patriarchy statistics. But they probably are in the end the most important—the telling pattern is that the higher you look, the maler it gets. If a society really had a stable, female-dominated power structure for an extended period of time even I would eventually question whether it was really still a patriarchy.

In my own area of research things are messier, because families and workplaces differ so much and power is usually jointly held. But I'm confident in describing American families as mostly patriarchal.

Maybe the most basic indicator is the apparently quaint custom of wives assuming their husbands' names. This hasn't generated much feminist controversy lately. But to an anthropologist from another planet, this patrilineality would be a major signal that American families are male-dominated.

Among U.S.-born married women, only 6 percent had a surname that differed from their husband's in 2004 (it was not until the 1970s that married women could even function legally using their "maiden" names). Among the youngest women the rate is higher, so there is a clear pattern of change—but no end to the tradition in sight.

Of course, the proportion of people getting married has fallen, and the number of children born to non-married parents has risen. Single parenthood—and the fact that this usually means single motherhood—reflects both women's growing independence and the burdens of care that fall on them (another piece of the patriarchal puzzle). This is one of many very important changes. But they don't add up to a non-patriarchal society.