Fig. 4: Optimal strategies in the model with equal intensity of competition within each compartment.
A Change in the fitness landscape with the competition intensity k = kHH = kEE. Colored lines: contours of equal sensitivities delimiting the optimal strategies (as shown in panel C): solid line, between strategies I and II; dashed line, between I and IV. Black lines: limit contours (solid line: limit of no competition, from the baseline model; dashed and dotted lines: limit derived from the number of microbes at equilibrium). Other parameters: tmax = 30, nE(0) = 1, nH(0) = 0. B Number of microbes in the two compartments in function of time, for the parameters combinations indicated by colored stars in panel A. When there is competition of same intensity in each of the compartments, there always exists a positive equilibrium. C Change in the contour lines delimiting the regions of optimality of the strategies with increasing k (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); dashed colored lines: between strategy I and IV. Other parameter: tmax = 30. The region of optimality of strategy I tends to expand until it converges to the contour of equal sensitivities of the number of microbes at equilibrium (black dashed line). The black dotted line is also derived from the number of microbes at equilibrium and delimits the area of optimality of strategy IV.
