I was looking at old papers mentioning Epstein and I noticed a graph similar to the FBI declassified pedo symbol: http://magaimg.net/img/8yb1.png

Replicator dynamics graphs have been around for a while. They're a way to show how specific game theoretic strategies play out over time. E.g. this evolutionary game theory textbook from 1996 has the same type of graph on page 91: https://books.google.com/books?id=m98ed0_Na1sC&pg=PA91#v=onepage&q&f=false

They're related to competition, reproduction, defection, cooperation, etc. played out over large timescales for many organisms.

One of the scientists closest to Epstein is Martin Nowak from Harvard's PED ("program for evolutionary dynamics").

I'll add anything else that I find here.