Say you’re an alien trying to figure out the strange cultural brew that is the United States. You want to know how the country has changed over time—which states are similar to each other and which are different, how ideas have spread from coast to coast, whether particular regions like to stick to tradition or groove on the unique. You have a special telescope that lets you keep track of one attribute, state-by-state, and you have a hundred years to sit and look through it.
What do you set it to—political affiliation? Average income? Favorite sport?
What about number of Jennifers?
Sociologists at the Sapienza University of Rome recently published a paper in Proceedings of the National Academy of Sciences which tracked baby names in the United States over more than a century. After looking at the changing popularity of Jennifers (and Cynthias, Barbaras, Patricias, Susans, and so on) in all fifty states, they’ve come out with maps that show which states have similar taste in names from year to year.