This starburst is the result of an experiment in visualizing the relationships between history specializations. The circles (or nodes) represent specializations, and are colored and sized by the number of historians in my sample who claimed that specialization. The lines (or edges) represent a connection between subfields, and are sized and colored by the number of historians who specialize in both of the connected specializations. The resulting network is beautifully dense with connections, and by plotting it in Tableau Public, we can explore this universe with filters, zooming, and highlighting (more information and instructions are below the viz. If the filters are slow, you can download the whole thing and open on your own computer with a free copy of Tableau Reader).