The taxonomy of the wide-ranging changeable hawk-eagle is complex and confusing, with few authorities agreeing on whether the species in fact houses a species complex. Gamauf "et al." (2005) analyzed mtDNA cytochrome "b" and control region sequence data of a considerable number of specimens of the crested hawk-eagle and some relatives. Despite the large sample, even the most conspicuous dichotomy - that between the crested and crestless groups - was not as well resolved as it might have been expected to be. At least one widely accepted genetic study has resulted in a recent revision to the recognition of a new species, as the Flores hawk-eagle has traditionally been treated as a subspecies of the changeable hawk-eagle, but it is now often treated as a separate species, "N. floris". The Flores and changeable hawk-eagles are regarded as sister species. The three small-island taxa ("N. c. andamanensis", "N. c. vanheurni", and "N. floris") as a whole each appear as monophyletic lineages. Their placement is even more unresolved, with "N. floris" being apparently a very ancient lineage. The other two seem quite certainly to derive from "N. c. limnaeetus". The latter taxon has a confusing phylogeny. Different lineages exist that are apparently not stable in space and time, are best described as polytomy, from which the similar island taxa derive. Obviously, "N. c. limnaeetus" does not represent a monophyletic lineage. Neither the biological nor the phylogenetic species concepts, nor phylogenetic systematics can be applied to satisfaction. The crested group apparently is close to becoming a distinct species. The island taxa derived from "N. c. limnaeetus" appear to have undergone founder effects, which has restricted their genetic diversity. In the continental population, genetic diversity is considerable, and the evolutionary pattern of the two studied genes did not agree, and neither did the origin of specimens show clear structures. "N. c. limnaeetus" thus is best considered a metapopulation.