Survivorship data for salmon and fathead minnow.

(Top panel) Experimental data illustrating a non-monotone survivorship curve for two species of salmon, Oncorhynchus tshawytscha and Salmo salar [30, 31], versus Se body-burden measured in μg Se per g dry wt tissue. (Bottom panel) A sigmoid survivorship concentration-response curve measuring a cumulative toxic effect for Fathead minnow (Pimephales promelas). Data obtained from [33].