The distribution of galaxy morphological types and the morphology-mass
  relation in different environments at low redshift
  We use \sim 2000 galaxies belonging to different environments to show how the
fractions of different galaxy morphological types vary with global environment
and as function of galaxy stellar mass at low redshift. Considering mass
limited galaxy samples with log10 M\star/M\bigodot>= 10.25, we find a smooth
increase/decline in the fraction of Es-S0s/late type galaxies going from single
galaxies, to binaries, to groups. Considering all environments, the fractional
variation is more conspicuous for S0s and late-types than for ellipticals
solely due to a sharp enhancement/dearth of S0s/late-types in clusters compared
to other environments. The morphological distribution of galaxies in the mass
range 10.25 < log10 M\star/M\bigodot < 11 is rather independent both of galaxy
stellar mass and global environment, except in clusters. The morphologies of
galaxies more massive than log10 M\star/M\bigodot = 11 are instead a function
of both galaxy mass and global environment. The morphology-mass relation
therefore changes with global environment, showing that galaxy stellar mass
cannot be the only parameter driving the morphological distribution of
galaxies. The morphology-mass relations for S0 and late-type galaxies in
clusters are peculiar compared to other environments, and this strongly
suggests that cluster-specific effects act on these two types of galaxies, and
that a significant number of S0s in clusters has a different origin with
respect to S0s in other environments.
