New Caledonia-Australian connections: biogeographic patterns and geology

A review is presented of current knowledge of the tectonic rifting of eastern Gondwana in the context of possible land continuity between Australia and New Caledonia and the dating of events. Comment is made on the level of endemicity of the modern-day biota of NewCaledonia, with examples of phylogenetic analyses, biogeographic patterns and estimated divergence dates among particular taxa, including birds (kagu-sunbittern clade), Nothofagus and Myrtaceae. The geological history of the region is complex but there is evidence of land persisting into the Cenozoic (Paleocene/Eocene) that possibly allowed old biota to persist. Vicariance explanations of divergences cannot be justifiably dismissed in favour of long-distance, over-water dispersal for such taxa.