Distribution of major mergers in the |cos θ_orb| versus cos θ_spin plane. Stars and circles correspond to BL and BD galaxies, respectively. The colour coding represents the stellar mass ratio (top panel) and the gas fraction (bottom panel). Grey hatched regions indicate the angular thresholds used to classify merger types, as defined in Fig. 7. Major mergers experienced by BL galaxies tend to be more coplanar and corotating, and are associated with higher stellar mass ratios and gas fractions compared to those in BD galaxies.