Christopher C Witt

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Deep avian evolutionary relationships have been difficult to resolve as a result of a putative explosive radiation. Our study examined approximately 32 kilobases of aligned nuclear DNA sequences from 19 independent loci for 169 species, representing all major extant groups, and recovered a robust phylogeny from a genome-wide signal supported by multiple(More)
Hummingbirds are an important model system in avian biology, but to date the group has been the subject of remarkably few phylogenetic investigations. Here we present partitioned Bayesian and maximum likelihood phylogenetic analyses for 151 of approximately 330 species of hummingbirds and 12 outgroup taxa based on two protein-coding mitochondrial genes (ND2(More)
The tempo of species diversification in large clades can reveal fundamental evolutionary mechanisms that operate on large temporal and spatial scales. Hummingbirds have radiated into a diverse assemblage of specialized nectarivores comprising 338 species, but their evolutionary history has not, until now, been comprehensively explored. We studied(More)
Theoretical and empirical studies of life history aim to account for resource allocation to the different components of fitness: survival, growth, and reproduction. The pioneering evolutionary ecologist David Lack [(1968) Ecological Adaptations for Breeding in Birds (Methuen and Co., London)] suggested that reproductive output in birds reflects adaptation(More)
In the context of a recently published phylogenetic estimate for 151 hummingbird species, we provide an expanded informal taxonomy, as well as a formal phylogenetic taxonomy for Trochilidae that follows the precepts of the PhyloCode, but remains consistent with the hierarchical nomenclature of the Linnaean system. We compare the recently published(More)
Ratites (ostriches, emus, rheas, cassowaries, and kiwis) are large, flightless birds that have long fascinated biologists. Their current distribution on isolated southern land masses is believed to reflect the breakup of the paleocontinent of Gondwana. The prevailing view is that ratites are monophyletic, with the flighted tinamous as their sister group,(More)
A well-tested set of primers to amplify regions spread across the avian genome Rebecca T. Kimball *, Edward L. Braun , F. Keith Barker , Rauri C.K. Bowie , Michael J. Braun , Jena L. Chojnowski , Shannon J. Hackett , Kin-Lan Han , John Harshman , Victoria Heimer-Torres , Wallace Holznagel , Christopher J. Huddleston , Ben D. Marks , Kathleen J. Miglia ,(More)
The tendency for flying organisms to possess small genomes has been interpreted as evidence of natural selection acting on the physical size of the genome. Nonetheless, the flight-genome link and its mechanistic basis have yet to be well established by comparative studies within a volant clade. Is there a particular functional aspect of flight such as brisk(More)
The taxonomy of lice (Insecta: Phthiraptera) is often heavily influenced by host taxonomy. The use of host information to define genera of avian lice in the widespread Degeeriella complex has been prevalent but has created problems. Several workers have suggested that genera defined on the basis of host association are not monophyletic. We used sequences of(More)
It has often been suggested that the genome sizes of birds are constrained relative to other tetrapods owing to the high metabolic demands of powered flight and the link between nuclear DNA content and red blood cell size. This hypothesis predicts that hummingbirds, which engage in energy-intensive hovering flight, will display especially constrained(More)