Chromosome Comparisons of Australian Species.

The represent a diverse group of closely related to Although they have radiated extensively in Australia, they have been the focus of few studies. Here, we characterized the karyotypes of 12 species from several species groups and showed that they have undergone similar types of karyotypic change to those seen in . This includes heterochromatin amplification involved in length changes of the sex and 'dot' chromosomes as well as the autosomes, particularly in the group of species. Numerous weak points along the arms of the polytene chromosomes suggest the presence of internal repetitive sequence DNA, but these regions did not C-band in mitotic chromosomes, and their analysis will depend on DNA sequencing. The nucleolar organizing regions (NORs) are at the same chromosome positions in as in and the various mechanisms responsible for changing arm configurations also appear to be the same. These chromosomal studies provide a complementary resource to other investigations of this group, with several species currently being sequenced.