Induction of supernumerary ovary pairs by feeding with the M0 + M10 fraction. Test worms with acquired sexuality induced significantly more supernumerary ovary pairs by feeding with the M0 + M10 fraction than that with chicken liver for 2 weeks (Welch's t-test: nM0 + M10 = 25, nLiver = 25; P = 1.59E-12). Error bars represent the standard error. The M0 + M10 fraction of Dugesia ryukyuensis was obtained as described in Figure 6. To prepare test food, the M0 + M10 fraction was mixed with 150 μl of chicken liver homogenate and then freeze-dried.