![]() ![]() In contrast, the radiation of the New Zealand moa could potentially be much more ancient, because the landmass broke from Antarctica/Australia ≈80 million years ago (mya). Geologically young island archipelagos such as the Galápagos Islands and Hawaii are renowned for their relatively recent passerine adaptive radiations, from which the classical allopatric mode and tempo of evolution have been inferred. The spectacular radiation of moa lineages involved significant changes in body size, shape, and mass and provides another example of the general influence of large-scale paleoenvironmental changes on vertebrate evolutionary history. These events resulted in the geographic isolation of lineages and ecological specialization. However, a cycle of lineage-splitting occurred ≈4–10 million years ago, when the landmass was fragmented by tectonic and mountain-building events and general cooling of the climate. Molecular dating estimated the most recent common ancestor of moas existed after the Oligocene drowning of New Zealand. We used longer sequences of the control region and nine other mtDNA genes totaling 2,814 base pairs to derive a strongly supported phylogeny of the 14 moa lineages. When results from genetic typing and previous molecular sexing were combined, at least 33.6% of the specimens were incorrectly classified. One of the newly detected lineages was a genetically divergent form of Megalapteryx originally described as a separate species, two more were lineages of Pachyornis in southern and northeastern New Zealand, and two were basal lineages of South Island Dinornis. The sequences detected 14 monophyletic lineages, 9 of which correspond to currently recognized species. We therefore extracted ancient DNA from 125 specimens and genetically typed them for a 658-bp mtDNA control region sequence. The tempo and mode of evolution of the extinct giant moas of New Zealand remain obscure because the number of lineages and their divergence times cannot be estimated reliably by using fossil bone characters only. ![]()
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