Parallel-sequencing of early-type and spiral galaxies
  Since Edwin Hubble introduced his famous tuning fork diagram more than 70
years ago, spiral galaxies and early-type galaxies (ETGs) have been regarded as
two distinct families. The spirals are characterized by the presence of disks
of stars and gas in rapid rotation, while the early-types are gas poor and
described as spheroidal systems, with less rotation and often non-axisymmetric
shapes. The separation is physically relevant as it implies a distinct path of
formation for the two classes of objects. I will give an overview of recent
findings, from independent teams, that motivated a radical revision to Hubble's
classic view of ETGs. These results imply a much closer link between spiral
galaxies and ETGs than generally assumed.
