SFR density as a function of redshift for different SFR–M_* relations (different colors). The different linestyles show the results by cutting the galaxy main sequence at different minimum galaxy masses, M_min = 10⁶ M_⊙ (dotted), 10⁷ M_⊙ (solid) and 10⁸ M_⊙ (dashed). The wide blue line shows the fit by Madau & Fragos (2017). The markers show observed data points: the blue dots are are taken from Madau & Dickinson (2014), the orange diamonds are from Casey et al. (2018), and the purple squares are taken from Gruppioni et al. (2020).