Evolution of the stellar mass as a function of v_max/v_infall (top left panel), the gas mass as a function of m_sub/m_infall (top right panel), and the r- and U-band magnitudes as a function of v_max/v_infall (bottom left and right panels) for galaxies with 11.5 < log(m_peak/h⁻¹ M_⊙) < 12.0. The symbols represent the data from the MTNG simulation (as shown in Fig. 3), while the dash-dotted lines represent the analytic models described in Sect. 3.2. The different colours represent different host halo masses, as labelled.