Genomic support for a moa-tinamou clade and adaptive morphological convergence in flightless ratites.
One of the most startling discoveries in avian molecular phylogenetics is that the volant tinamous are embedded in the flightless ratites, but this topology remains controversial because recent morphological phylogenies place tinamous as the closest relative of a monophyletic ratite clade. Here, we integrate new phylogenomic sequences from 1,448 nuclear DNA loci totaling almost 1 million bp from the extinct little bush moa, Chilean tinamou, and emu with available sequences from ostrich, elegant crested tinamou, four neognaths, and the green anole. Phylogenetic analysis using standard homogeneous models and heterogeneous models robust to common topological artifacts recovered compelling support for ratite paraphyly with the little bush moa closest to tinamous within ratites. Ratite paraphyly was further corroborated by eight independent CR1 retroposon insertions. Analysis of morphological characters reinterpreted on a 27-gene paleognath topology indicates that many characters are convergent in the ratites, probably as the result of adaptation to a cursorial life style.
Department of Natural History, Royal Ontario Museum, Toronto, Ontario, CanadaDepartment of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada allanb@rom.on.ca.
Allan J
AJ
Baker
Department of Natural History, Royal Ontario Museum, Toronto, Ontario, Canada allanb@rom.on.ca.
Oliver
O
Haddrath
Ontario Institute for Cancer Research, Toronto, Ontario, Canada.
John D
JD
McPherson
Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada.
Alison
A
Cloutier
D000222:Adaptation, Physiological; D000818:Animals; D001499:Bayes Theorem; D019143:Evolution, Molecular; D016678:Genome; D016013:Likelihood Functions; D008957:Models, Genetic; D046108:Palaeognathae / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics* / Q000502:physiology; D010802:Phylogeny; D017422:Sequence Analysis, DNA
CR1 retroposon insertions; ancient DNA; little bush moa; morphological convergence; phylogenomics; ratite paraphyly