The Erdős–Rényi model of random graphs shows: if you have n items and greater than 1/n chance that any two random items are connected, the chance that almost all are connected in a “giant component” network approaches 1 as n gets large. No conspiracy theories needed. www.nature.com/immersive/d4...

Also, but really this is just repeating, they’re all descended from a common ancestor, so they’re all in the same family, let alone academic family. Degrees of separation, Kevin Bacon, etc., etc.