In this study we use 40 mitochondrial genomes, including five
new cockatoo mitochondrial genomes, together with multiple fossil
calibrations to estimate the timing of radiation for Nestoridae,
Cacatuidae and Psittacidae. In addition, three mitochondrial and
three nuclear DNA genes with near-complete taxon sampling from
the four recognized subfamilies of Cacatuidae (Microglossinae,
Calyptorhynchinae, Cacatuninae and Nymphicinae) (Schodde,
1997) facilitated an examination of the phylogenetic relationships
and divergence dates of cockatoos, as well as the mode and tempo
of their evolution. Lastly, upon examination of the historical timescale
and biogeography of the Australasian region, the potential
environmental influence that may have led to the diversification
of Cacatuidae is discussed.