Figure 3.

Coexistence and bistability of two strains. (a) Conditionally neutral region of growth-lag trait space where coexistence or bistability occur, coloured by the neutral frequency (equation (3.5)). As ν₂ > ν₁ in this example, mutants in the lower branch (γ < 0) of the conditionally neutral region coexist with the wild-type, while mutants in the upper branch (γ > 0) are bistable. Blue and red points mark example mutants used in (b) and (c). (b) Selection coefficient s(x) as a function of frequency x for mutants with neutral frequency , where one mutant has coexistence (blue) and the other is bistable (red). (c) Mutant frequency x(r) as a function of competition round r for blue and red mutants from (a) and (b), each starting from two different initial conditions. The black dashed line marks the neutral frequency . The yields are ν₁ = 10³ and ν₂ = 10⁴ in all panels.