Evolution of the molecular gas fraction with redshift plotted for the same ALPINE galaxies (red circles) and CO-detected MS SFGs with the same color coding per redshift bin as in Fig. 6, but restricted to the z >  0 − 5.9 progenitors of, respectively, Milky Way-like galaxies at z = 0 with stellar masses in the range of ∼10^10.8 − 10^11.2 M_⊙ for a halo mass of 10¹³ M_⊙ (left panel), and more massive z = 0 galaxies with M_stars ∼ 10^11.4 − 10^11.7 M_⊙ for a halo mass of 10¹⁴ M_⊙ (right panel). We consider the stellar masses of the progenitors as a function of redshift listed in Table 2, obtained from the multi-epoch abundance-matching predictions of Behroozi et al. (2019). The number drawn in each redshift bin corresponds to M_halo at this epoch. A different molecular gas fraction evolution from z = 5.9 to z = 0 is observed for the respective progenitors of the 10¹³ M_⊙ and 10¹⁴ M_⊙ halo mass galaxies at z = 0.