title: Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution.
abstract: The evolution of the ratite birds has been widely attributed to vicariant speciation, driven by the Cretaceous breakup of the supercontinent Gondwana. The early isolation of Africa and Madagascar implies that the ostrich and extinct Madagascan elephant birds (Aepyornithidae) should be the oldest ratite lineages. We sequenced the mitochondrial genomes of two elephant birds and performed phylogenetic analyses, which revealed that these birds are the closest relatives of the New Zealand kiwi and are distant from the basal ratite lineage of ostriches. This unexpected result strongly contradicts continental vicariance and instead supports flighted dispersal in all major ratite lineages. We suggest that convergence toward gigantism and flightlessness was facilitated by early Tertiary expansion into the diurnal herbivory niche after the extinction of the dinosaurs.
authors.affiliation: Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia.
authors.forename: Kieren J
authors.initials: KJ
authors.lastname: Mitchell
authors.affiliation: Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia.
authors.forename: Bastien
authors.initials: B
authors.lastname: Llamas
authors.affiliation: Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia.
authors.forename: Julien
authors.initials: J
authors.lastname: Soubrier
authors.affiliation: Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia.
authors.forename: Nicolas J
authors.initials: NJ
authors.lastname: Rawlence
authors.affiliation: School of Biological Sciences, Flinders University, South Australia 5001, Australia.
authors.forename: Trevor H
authors.initials: TH
authors.lastname: Worthy
authors.affiliation: Landcare Research, Post Office Box 40, Lincoln 7640, New Zealand.
authors.forename: Jamie
authors.initials: J
authors.lastname: Wood
authors.affiliation: Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia. South Australian Museum, North Terrace, South Australia 5000, Australia.
authors.forename: Michael S Y
authors.initials: MS
authors.lastname: Lee
authors.affiliation: Australian Centre for Ancient DNA, School of Earth and Environmental Sciences, University of Adelaide, North Terrace Campus, South Australia 5005, Australia. alan.cooper@adelaide.edu.au.
authors.forename: Alan
authors.initials: A
authors.lastname: Cooper
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D004247:DNA / Q000235:genetics*; D005426:Flight, Animal; D005580:Fossils; D008969:Molecular Sequence Data; D009520:New Zealand; D046108:Palaeognathae / Q000145:classification* / Q000235:genetics; D010802:Phylogeny; D020310:Struthioniformes / Q000145:classification* / Q000235:genetics
chemical_list: D004247:DNA