Taxonomy
The Gang-gang Cockatoo was most often allied with the white cockatoos of the genus Cacatua. This has always been controversial due to the unusual appearance and coloration of the bird, especially its sexual dichromatism. New research has finally resolved the matter, with the Gang-gang Cockatoo being recognized as a distinctive early offshoot of the calyptorhynchine (dark) cockatoos (Brown & Toft, 1999). Considering the robust phylogeny of the cockatoos now established, a comparison of characters gained and lost during the evolution of cockatoos suggests that the Gang-gang Cockatoo - while of course much changed and adapted during the perhaps 20 million years since its last common ancestor with any other living species lived - is probably still very similar in overall appearance to how the earliest cockatoos would have looked, and certainly the most primitive-looking of the species alive today.
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