Population dynamics and evolutionary dynamics for the pair showing a cheap defense tradeoff (panels in the same row are data from the same run of chemostat). A, C, E, and G show rotifer and algal population dynamics, corresponding to B, D, F, and H, respectively, which show the changes in algal clonal frequencies in the same chemostat. The mean and range of dilution rates during the experiments were 0.44 (0.40–0.50) d−1 (A and B), 0.49 (0.46–0.52) d−1 (C and D), 0.48 (0.42–0.56) d−1 (E and F), and 0.49 (0.48–0.51) d−1 (G and H).