Fig. 2.

Comparison of the relationship between diversity/discordance and cross-immunity for the symmetric 5 × 5 system (black diamonds) and an asymmetric 2 × 5 system (gray squares) for the deterministic (A) and stochastic (B) models. Each point in the stochastic figures represents the mean of simulations for which cross-immunity fell within a bin of 0.02. Parameter values for the deterministic model: β = 4, σ = 1, μ = 0.02. (C) Patterns of dominance observed at high levels of cross-immunity for equivalent deterministic and stochastic two-locus systems. Alleles of locus 1 are represented by rows, and alleles of locus 2 are represented by columns, such that each square in the matrix represents one allelic combination. Black squares represent dominance at equilibrium of particular combinations, and white squares represent the absence of particular combinations. Gray squares represent subdominant (in terms of prevalence) allelic combinations.