Intraspecific Variation Studies in Australian Birds, Subspecies, Isolates and Ultrataxon Concepts: How Close Are We to a Final Designation of Forms?

Abstract

SummaryHere I: (i) briefly review of the history of the subspecies concept in Australia; and (ii) use the new Schodde-Mason Directory of Australian Passerine Birds as the vehicle, to ask if we have now reached a reasonable finality in defining and naming of geographic forms (subspecies) in Australian birds. I do this by testing the Schodde & Mason (1999) conclusions against the findings of previous workers. There is good agreement for differentiated, isolated populations of species (e.g. those inhabiting Tasmania and southwestern Australia). Widely distributed species, subject to multiple and varying selection pressures in different parts of their range, and where variation cannot be expected to come in tidy packages, remain a problem. I conclude that the authors have done a good job in designating and naming geographic variation and forms throughout. No two workers, of course, will completely agree on the level of distinctness that merits a name. The Schodde-Mason volume provides an excellent basis for future distributional and molecular studies.