Figure 4. The evolution of persister function, with less extreme differences in persister and nonpersister survival and growth, and differences in efficiency of resource use.

(A) ESS persister allocation (π*) is a decreasing function of the relative survival (s) of nonpersister cells. We assume: p ₀ = 1, T = 5, g = 0, a = 1 and a range of z ₀. (B) ESS persister allocation (π*) is an increasing function of the relative growth rate (g) of persister cells. We assume: p ₀ = 1, T = 5, s = 0, a = 1 and a range of z ₀. (C) ESS persister allocation (π*) may depend on the relative competitive strain on resources imposed by persister cells (a), but this is negligible when they appear only infrequently in bacterial populations (low π*). We assume: p ₀ = 1, T = 5, s = 0, g = 0 and a range of z ₀.