Fig. 4

Structural diagrams of all functional networks with Q-values \(\ge\) 10 for illustrating their mutual topological relationships; (A) for Off–On switches, and (B) for On–Off switches. The networks are organized along the vertical axis with respect to the number of links in the topology. Each dot denotes a network whose Q-value is proportional to the dot size. The topologies that differ only with one edge are connected. The green dots and links are highlighted topologies and their connections, illustrating the evolution paths starting from the simplest topology to the top robust network