Genome Biol. Evol. 4(11):1061–1079. doi:10.1093/gbe/evs084
In the first paragraph of the Materials and Methods section, the sentence beginning “A range of copper concentrations in SWM were assayed …” should be replaced with the following sentence, which corrects the moderate copper concentration: “A range of copper concentrations in SWM were assayed: 1) copper-deprived: SWM containing no copper at all (-Cu); 2) moderate copper: a base SWM containing the standard 0.004 mM CuSO4 (SWM); and three levels of 3) copper overdose: base SWM supplemented with 0.1 mM CuSO4 (0.1), 4) 0.25 mM CuSO4 (0.25), and 5) 1.0 mM CuSO4 (1.0).” The authors regret the error.