Figure legends
FIGURE 1 A schematic illustration about how natural enemies and migration from core habitats (in red color) may affect local adaptation in edge habitats (blue color). Populations of a focal species (victim) may evolve alone (a), or with immigrations from the core habitats (b). Victim/enemy populations in the edge habitats may coevolve without immigration (c), with immigration of enemy (d), or with joint immigration of enemy and victim (e) from the core habitats. Predicted strength of evolutionary driving forces (genetic variation and the efficiency of abiotic selection) in victim populations are indicated as the number of ‘+’ signs.
FIGURE 2 Average bacterial population density (± se) for each treatment during the evolution experiment.
FIGURE 3 Growth performance of bacterial populations sampled from the (co)evolution lines, measured in the absence of phages and without immigration. Dashed line (mOD = 289) referred to the ancestral genotype. Scatter data points are shown together with boxplot summaries (the boxes covering the 25th to 75th percentiles of the data, the middle lines being the medians, and the whiskers extended from the boxes hinging to the smallest or largest value no further than 1.5 times of interquartile range). Asterisks represent significant difference in bacterial density from the ancestor (nsP> 0.05, *P < 0.05,**P < 0.01,***P < 0.001,****P < 0.0001).
FIGURE 4Resistance of bacteria from coevolution lines against phages from their own microcosms (top), or phages from the core habitats (bottom). Scatter data points are shown together with boxplot summaries.