Snapshots of the orbital evolution of planetesimals for (a) t = 127 323 yr, (b) 397 887 yr, and (c) 572 957 yr in the reference case (see Table 1 for the setting). Horizontal and vertical axes are the semi-major axis and eccentricity, respectively. Red and blue circles indicate the planetesimals with positive and negative Jacobi energy, respectively; orange circle represents the migrating planet. Green dotted lines indicate the positions of 2:1, 5:3, and 3:2 mean motion resonances with the planet.