Samples of the simulated dataset, each in a different colour. In the left plot we show their mocked SFHs: in the upper panel the star formation rate normalised by the total stellar mass in Gyr⁻¹ and in the lower one the nine stellar mass percentiles, together with three dashed grey lines indicating when 25%, 50%, and 75% of the total stellar mass has been formed. In the right plot, we show the simulated normalised spectra corresponding to these SFHs (same colours) for two different values of metallicity: in the upper panel we fix [M/H] = −2.3, and in the lower one [M/H] = 0.4, which are respectively the minimum and maximum bins of [M/H] in the simulation.