Figure 1.

Examples of life-history trends in marine and terrestrial harvested populations. Fisheries: age at maturity of Atlantic cod ((a) Gadus morhua; unit 3PS) [4] and American plaice ((b) Hippoglossoides platessoides; unit 2J3 K) [5], plotted against the year the cohort was born. Hunting: changes in age-adjusted deviations from average horn length (c) and breeding value (d) for horn length in cohorts of bighorn sheep (Ovis canadensis) at Ram Mountain, Alberta, Canada [6]. End of harvesting of the population is indicated by the dashed vertical line. Cohort-specific horn growth during the second and third year of life of Stone's sheep (O. dalli) males (e) from the heavily harvested Peace area (dashed line) and lightly harvested Skeena area (solid line) of northern British Columbia, Canada [7].