Mass–excitation (MEx) diagram for galaxies and AGN from the MAMBO lightcone selected with 0.3 ≤ z ≤ 1.0 and $m_{H_{\text{E}}}<24$. Galaxies are shown in grey, while AGN are colour-coded from blue to red according to the ratio of the emission line flux of [O III] from the AGN component with respect to the total (AGN + host galaxy). The solid black lines show the empirical division found in Juneau et al. (2011) to separate AGN (above the line) from SF galaxies (below the line) and composite galaxies (between the two lines).