Galaxies and Cladistics
  The Hubble tuning fork diagram, based on morphology and established in the
1930s, has always been the preferred scheme for classification of galaxies.
However, the current large amount of multiwavelength data, most often spectra,
for objects up to very high distances, asks for more sophisticated statistical
approaches. Interpreting formation and evolution of galaxies as a ?transmission
with modification' process, we have shown that the concepts and tools of
phylogenetic systematics can be heuristically transposed to the case of
galaxies. This approach, which we call ?astrocladistics', has successfully been
applied on several samples. Many difficulties still remain, some of them being
specific to the nature of both galaxies and their diversification processes,
some others being classical in cladistics, like the pertinence of the
descriptors in conveying any useful evolutionary information.
