They are common in some metropolitan areas, for example Perth and Melbourne, and common to abundant in open habitats which offer at least some scattered trees for shelter. They appear to have been self-introduced to Tasmania. Galahs are found in all Australian states, and are absent only from the driest areas and the far north of Cape York Peninsula. Typical birds are about 350mm long and weigh between 300 and 400 grams. The sexes appear similar, however generally adult birds differ in eye color the male has a very dark brown (almost black) iris, and the female has a mid-brown/red iris. They have a pale grey to mid-grey back, a pink face and chest, and a light pink crest. The Galah has also been shown to be capable of hybridizing with the Cockatiel, producing offspring described by the media as 'Galatiels'. The significance of these two (and other) characters shared by the Cacatuinae had previously been explained away in earlier studies by strict application of parsimony on misinterpreted data.Īviary-bred crosses of galahs and Major Mitchell's Cockatoos have been bred in Sydney, with the tapered wings of the galah and the crest and colors of the Major Mitchell's, as well as its plaintive cry. Today, the galah is seen, along with Major Mitchell's Cockatoo, as an early divergence from the white cockatoo lineage which have not completely lost their ability to produce an overall pink (Major Mitchell's) or pink and grey (galah) body plumage, while already being light in color and non-sexually dimorphic. It fell to the study of Brown & Toft (1999) to compare the previously available data with their mitochondrial 12S rRNA sequence research and resolve the issue. Ignorance of this fact, however, led to attempts to resolve the evolutionary history and prehistoric biogeography of the cockatoos, which ultimately proved fruitless because they were based on invalid assumptions to start with. In consequence, it was thought that the ancestors of the galah, the cockatiel and Major Mitchell's Cockatoo diverged from the main white cockatoo line at some stage prior to that group's main radiation this was indeed correct except for the placement of the cockatiel. Early DNA studies allied the galah with the cockatiel or placed it close to some Cacatua species of completely different appearance. There are obvious morphological similarities between the galah and the white cockatoos that make up the genus Cacatua and indeed the galah was initially described as Cacatua roseicapilla. It was separated in the monotypic genus Eolophus, but the further relationships were not clear. The classification of the Galah was difficult.
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