Figure 1.

Context for selection in Windermere pike (E. lucius) and associated temporal changes in pike phenotypic variance. (a) Nonlinear relationship between pike body length and an individual's survival probability through (i) natural selection and (ii) fishery selection, separated into three time periods covering the entire time series. Note that natural selection tended to be increasingly stabilizing over time while fishery selection tended to be less disruptive. (b) Nonlinear relationship between large pike (55 cm body length and longer) somatic growth rate (cm yr⁻¹) and an individual's survival probability through fishery selection with 95 per cent confidence intervals. (c) Observed time series of natural log-transformed variance for (i) lifetime somatic growth rate (von Bertalanffy asymptotic length) and (ii) length at age 3 years (solid line) and age 4 years (thin dashed line) (both in cm², y-axis on a log scale). Bold dashed line is a smoother of the effect of year class. (d) Unbiased change in phenotypic variance with 95 per cent confidence intervals for pike lifetime somatic growth rate (von Bertalanffy asymptotic length in cm², data pooled by groups of 5 year classes, y-axis on a log scale).