Frequency of stellar mass ratios of ETG galaxies involved in mergers for the case of z = 1 progenitors with M_r(z = 0) < −19.7 (i.e. stellar masses above  ~10¹⁰   h^-1   M_⊙) and their z = 0 descendants for a total of four mergers per descendant. The solid line shows the sum of all merger events, dashed corresponds to mergers between central galaxies, dotted to mergers between a central and one of its satellites. The shaded region corresponds to ratios above the limit for a major merger (mass ratio of 1/3 and higher).