Figure 5.

Population density of a diffusion dispersed population across one dimensional space. The initial population density (bold dashed line) is near carrying capacity (u = 0.95, a² = 0.3, r = 1, D = 0.5), but introduced below the minimum radius of area determined to be critical for invasion success. (A) is collapsing to extinction without evolution (ε = 0), whereas (B) shows success of an invader with evolution (ε = 0.02) after initial decline. (C) The evolution of the mean value of the Allee threshold across space (where the initial distribution is given by the bold dashed line). The population density distribution and corresponding trait values (i.e., Allee threshold) are plotted at equal time increments (every 20 of 1200 model iterations).