The evolution of M*/MBH between z=2 and z=0

We propose a novel method to estimate M-*/M-BH, the ratio of stellar mass (M-*) to black hole mass (M-BH) at various redshifts using two recent observational results: the correlation between the bolometric luminosity of active galactic nuclei (AGN) and the star formation rate (SFR) in their host galaxies, and the correlation between SFR and M-* in star-forming (SF) galaxies. Our analysis is based on M-BH and L-bol measurements in two large samples of type I AGN at z similar or equal to 1 and 2, and the measurements of M-*/M-BH in 0.05 < z < 0.2 red galaxies. We find that M-*/M-BH depends on M-BH at all redshifts. At z similar or equal to 2, M-*/M-BH similar to 280 and similar to 40 for M-BH = 108 and M-BH = 109 M-circle dot, respectively. M-*/M-BH grows by a factor of similar to 4-8 from z similar or equal to 2 to 0 with extreme cases that are as large as 10-20. The evolution is steeper than reported in other studies, probably because we treat only AGN in SF hosts. We caution that estimates of M-*/M-BH evolution which ignore the dependence of this ratio on M-BH can lead to erroneous conclusions.