This shows the PhD advisor relationships starting with Kevin McCurley. The nodes are clickable and take you to the mathematical genealogy site. I find it interesting that this goes back to Minkowski, Klein, Gauß, Ohm, Dirichlet, Fourier, Poisson, Laplace, and the Bernoullis. Some people have had two advisors, which is why this isn't just a line. I wonder how accurate this data is...