  It has been suggested that the bulge-to-total stellar mass ratio or feedback
from black holes (BHs), traced by the BH-to-(total stellar) mass ratio, might
establish a galaxy's specific star formation rate (sSFR). We reveal that a
galaxy's morphology -- reflecting its formation history, particularly
accretions and mergers -- is a far better determinant of the sSFR.
Consequently, we suggest that galaxy formation models which regulate the sSFR
primarily through BH feedback prescriptions or bulge-regulated disc
fragmentation consider acquisitions and mergers which establish the galaxy
morphology. We additionally make several new observations regarding current
($z\sim0$) star-formation rates. (i) Galaxies with little to no star formation
have bulges with an extensive range of stellar masses; bulge mass does not
dictate presence/absence on the `star-forming main sequence'. (ii) The (wet
merger)-built, dust-rich S0 galaxies are the `green valley' bridging population
between elliptical galaxies on the `red sequence' and spiral galaxies on the
blue star-forming main sequence. (iii) The dust-poor S0 galaxies are not on the
star-forming main sequence nor in the `green valley'. Instead, they wait in the
field for gas accretion and/or minor mergers to transform them into spiral
galaxies. Mid-infrared sample selection can miss these (primordial) low
dust-content and low stellar-luminosity S0 galaxies. Finally, the appearance of
the quasi-triangular-shaped galaxy-assembly sequence, previously dubbed the
Triangal, which tracks the morphological evolution of galaxies, is revealed in
the sSFR-(stellar mass) diagram.
