Comparison of the mass ratios in the single-planet and two-planet cases as a function of time and for different viscosities. Again, the planets are fixed at the 3:1 period ratio positions, as shown in the upper-left corner. In solid lines we show the mass ratios of the outer over the inner planet in the two-planet case, whereas the dashed lines represent the mass ratio of the single planets. Different flips are marked by circled numbers and can be explained by the impact that gap opening and depletion of the inner disk have on the accretion behavior of the planets.