Photometric relations. Galaxies are color-coded by Hubble type. In the top left panel, the solid line shows the K-band mass–radius relation from the GAMA survey (Lange et al. 2015), where stellar masses have been converted to [3.6] luminosities assuming ϒ_⋆ = 0.5 M_⊙/L_⊙. The dashed lines show a 0.4 dex deviation from the mean relation, corresponding to ∼2σ.