Figure 4

Structural changes of the growing networks: in-degree distribution, shortest path length, and the count of motifs. Three upper rows: NETMORPH results, three lower rows: CX3D results. Different curves correspond to different initial elongation rates , and the employed values are given in the legends (1, 2, 3, 6, 8, and 10 μ m/day for NETMORPH, 2, 6, 10, 14, and 22 μ m/day for CX3D). Grey interrupted lines indicate motifs that are significantly more frequent than in random networks (-test, 0.01 significance level). The corresponding numbers show for which parameters this holds; for example, 2 means "holds only for the two smallest values." For CX3D,  μ m/day was excluded since it gives too sparse random networks.