Appendix 1—figure 5. Minimum Spanning Tree (MST) in interaction trait space.

Left: 2D representation of MST of a typical snapshot of a simulation with $\delta =0.5$, $\lambda =300$, $\mu =0.001$, and $m=0.02$. The community in this snapshot consists of 667 strains. Here we used R-package vegan 2.4–5 to find the MST. Right: the set of 500 gray curves shows the sorted lengths of the edges of the MST versus their ranks (rank 1 = longest edge) for 500 snapshots from simulations with the aforementioned parameters. The red curve is the average of all curves and the red shaded area is the corresponding standard deviation. $R_1$ and $R_2$ are approximate lengths of short branches connecting strains within clusters ($R_1$), and long branches ($R_2$) connecting species. $N$ approximates the number of long branches or species.