Comparison of specific entropy production integrated over the lifetime of a star on the MS of the HR diagram (solid blue line) for stars of different masses (normalized to unity for a solar-mass star) with the specific entropy production of galaxies on the SFMS for galaxies of different masses (dashed red line; upper horizontal axis). The normalization of the SFMS evolves with redshift; here, it is normalized to unity at 10⁹ M_⊙.