Qualitative outcomes for the evolution of juvenile susceptibility when the trade-off is against (a) adult fecundity and (b) maturation. (a,b) Trade-off spaces where the following outcomes occur: minimum susceptibility (i.e. βJ = βA; MN); maximum susceptibility (i.e. βJ = dβA; MX); intermediate susceptibility (i.e. βA < βJ < dβA; CSS); repeller (RE); branching point (BR); repeller and a branching point (RE + BR). (c–f) Evolutionary simulations demonstrating some of these outcomes, with dashed lines indicating the singular strategies: (c) CSS; (d) RE; (e) BR; (f) RE + BR. Transmission is density-dependent. Fixed parameters: a0 = 2, b = 0.1, d = 3, f = 0.75, g0 = 0.25, q = 0.001, α = 0.5, βA = 2q/3, γ = 0.5.