Figure 4.

Variation in the magnitudes of evolutionary change, measured by the smaller of the two P-values describing the probability of harvest-induced evolutionary change, ℰ (equation 21), for different harvest regimes. The three panels correspond to selectivity curves with increasing steepness: (A) a = 0.5, (B) a = 5.9, and (C) a = 25. The vertical axis shows the length at 50% selectivity, measured as a fraction of the charr's maximum length, while b_H, which scales the density-dependent component of harvesting, is shown along the horizontal axis. The magnitudes of evolutionary changes are color-coded, with dark blue corresponding to large evolutionary change, while red indicates magnitudes of evolutionary change that are comparable to those occurring in the absence of harvesting. Values shown for each harvest regime are means of 15 replicate model runs.