Fig. 3: Optimal strategies in the model with competition in the host only.
A Change in the fitness landscape with the within-host competition intensity k = kHH. Colored lines: contours of equal sensitivities delimiting the optimal strategies (as shown in panel C). Black lines: limit contours (solid line: limit of no competition, from the baseline model; dashed line: limit derived from the number of microbes at equilibrium). Other parameters: tmax = 30, nE(0) = 1, nH(0) = 0. B Number of microbes in function of time, for the parameter combinations indicated by colored stars in panel A. When there is competition in the host only, there is an equilibrium only if migration is important enough. C Change in the contour lines delimiting the regions of optimality of the strategies with increasing k (within-host competition intensity). All the microbes are initially in the environment (nE(0) = 1, nH(0) = 0). Solid colored lines: limit between the regions of optimality of strategy I (increasing rH) and II (decreasing mH). Other parameter: tmax = 30. The region of optimality of strategy I tends to narrow down and shifts out of the m < 1 region to converge to the contour of equal sensitivities of the number of microbes at equilibrium (thin dashed line).
