Australian arid and semi-arid birds dance to their own beat: patchy habitat drives diverse patterns of diversification

Abstract

Comparative phylogeography offers a powerful way to diagnose the history of biotic stability of a geographic region of interest and its avifauna. We compared phylogeographical patterns and parameters of genetic diversity within and among eleven southern Australian bird species that are broadly co-distributed either in arid and semi-arid regions or in its more mesic habitats. MtDNA (ND2) divergence from four previously described phylogeographic breaks range from substantial to no structure. Likewise, there were no clear patterns with regard to patterns of genetic diversity and population expansion. Phylogeographic breaks are concordantly located, which suggests community composition is not completely ephemeral. Rather, species of more arid zones show variable historical responses depending on habitat preference and, perhaps, increased adaptability to different habitats, compared with studies of species from more mesic environments. Further insight into these questions of demographic history raised by the mtDNA data can be gained from multi-locus coalescent analyses. We present analyses of multilocus sequence data from two species.