(color online) A 4-node chaotic motif. The same as Fig. 5 with three 4-node GRNs considered. (a)–(c) Three 4-node chaotic GRNs, where solid/dashed lines denote active/repressive regulations. (d)–(f) Bifurcation diagrams of (a)–(c), respectively by plotting peak values of p₃ as a function of K with (d) h = 2.00, (e) h = 2.35, and (f) h = 2.50. (Adapted from Ref. [43]).