Flood-based minimization of regulatory networks of in silico organisms evolved in AND (A-C) and XOR (D-F) environments. Top panels (A and D) show the distribution of fitness for cells evolved in high mutation rates (red) and low mutation rates (black). Dot plots show the statistics of the flood minimization for populations of cells evolved in AND low mutation rate (B), AND high mutation rate (C), XOR low mutation rate (E), and XOR high mutation rate (F) environments. Gray dots show the effect on fitness of a random network minimization to the same degree as obtained by the flood analysis. Bar plots in (B, C, E, and F) show the distribution of minimization degree (decrease in number of links) for each type of evolved cells.