PARROT EVOLUTION AND PALEOGEOGRAPHIC EVENTS - MITOCHONDRIAL-DNA EVIDENCE

We sequenced 1,771 bp of three mitochondrial genes (12S rDNA, 16S rDNA , and cytochrome D) of nine New World parrot genera (Amazona aestiva, Anodorhynchus hyacinthinus, Ara ararauna, Aratinga aurea, Cyanopsitta spixii, Deroptyus accipitrinus, Guaruba guarouba, Pionus menstruus, an d Pyrrhura picta) and compared them with the corresponding sequence of Australian parakeet (Melopsittacus undulatus). Phylogenetic analyses (maximum parsimony and maximum likelihood) showed that the Neotropical species we studied constitute two monophyletic groups: the long-taile d and the short-tailed species. The separation within the long-tailed species could be assigned to the late Oligocene-early Miocene, when pa leoenvironmental changes might have influenced this radiation. The lon g-tailed Neotropical and Australasian species diverged during the Cret aceous-Tertiary boundary, when South America and Australia were moving away from Antarctica (Gondwanaland fission). We also compared our dat a with the cytochrome b sequences of seven different genera of Austral asian parrots obtained by other investigators, and these comparisons a lso support the independent evolution of the Neotropical and Australas ian species. Analyses performed with 567 bp of partial sequences of 12 S rDNA and cytochrome b did net support or refute the hypothesis of mo nophyly of the Neotropical parrots with respect to an African species whose sequences were available. However, this analysis supported the v iew that the divergence between Neotropical short- and long-tailed tax a was older than the Oligocene-Miocene divergence among the long-taile d genera.