Figure 5.

Loss of mutualism in the forward (collapse) direction. Shown are the steady state species abundances of network A versus the bifurcation parameter κ as it increases from zero for six values of ζ, the amplitude of DN. Mutualism is lost for ζ > ζ_c, where 4.5 < ζ_c < 5.0. The network parameter values are ${\alpha }_i^{(X)}={\alpha }_i^{(Y)}=0.3$, ${\beta }_{ii}^{(X)}={\beta }_{ii}^{(Y)}=1$, γ = 1, h = 0.2, ρ = 0.5, μ_X = 10⁻⁴ and μ_Y = 10⁻⁴. The initial conditions are randomly chosen from the basin of the high abundance steady state.