Repeated DNA sequences and kangaroo phylogeny

Three highly repeated DNA sequences have been used to determine relationships of species within the Macropodidae (kangaroos and wallabies). Two highly repeated DNA sequences were isolated as buoyant density satellites in the red-necked wallaby and in the wallaroo-euro group. The third probe was a cloned representative of one class of highly repeated species from the red kangaroo. Radioactively labelled probes of these three repeated sequences were used to determine the incidence and distribution of each in number of macropodid species. The results were consistent with a monophyletic origin of the macropodid species and showed in particular, that the red-necked wallaby is closely related to the red kangaroo and to the euro-wallaroo group. In addition, the data indicated that the tammar and the agile wallaby were closely related. The results also favour the current taxonomic status of the eastern and western grey kangaroos as closely related but separate species.