Number of galaxies in the four stellar mass bins at different local densities. The stellar mass bins are colour coded and plotted with different symbols as in Figs 10 and 11: blue triangles (log M_* < 10.5), cyan squares (10.5 < log M_* < 11), green stars (11 < log M_* < 11.5) and red circles (log M_* > 11.5). The scale of the y-axis on the left side shows the number of galaxies in each stellar mass bin and local density bin, normalized by the total number of galaxies in the respective redshift bin. For comparison reasons we show the number of galaxies in each bin without this normalization on the right-hand side of each plot.