Fig. 3. Relationship between the concentrations of methyl farnesoate and analogs that elevated hemoglobin to 70% of the maximum level (x axis) and concentrations that caused a 50% incidence of male broods of offspring (y axis) in D. magna. Male offspring assessments were reported previously (Olmstead and LeBlanc, 2003). The 70% of maximal induction was used as the descriptor of relative potency for hemoglobin levels because this value could be interpolated from all of the concentration-reponse relationships depicted in Fig. 2. Correlation coefficient r²=0.999.