A phylogenomic tree of wood-warblers (Aves: Parulidae): Dealing with good, bad, and ugly samples.

The New World warblers (Parulidae) are a model group for ecological and evolutionary analyses. However, current phylogenetic relationships across this family are based upon few loci. Here we use ultraconserved elements (UCEs) to estimate a rigorous species-level phylogeny for the family.

Species-specific traits mediate avian demographic responses under past climate change.

Anticipating species' responses to environmental change is a pressing mission in biodiversity conservation. Despite decades of research investigating how climate change may affect population sizes, historical context is lacking, and the traits that mediate demographic sensitivity to changing climate remain elusive. We use whole-genome sequence data to reconstruct the demographic histories of 263 bird species over the past million years and identify networks of interacting morphological and life history traits associated with changes in effective population size (N) in response to climate warming and cooling.

Changes in the functional diversity of modern bird species over the last million years.

Despite evidence of declining biosphere integrity, we currently lack understanding of how the functional diversity associated with changes in abundance among ecological communities has varied over time and before widespread human disturbances. We combine morphological, ecological, and life-history trait data for >260 extant bird species with genomic-based estimates of changing effective population size () to quantify demographic-based shifts in avian functional diversity over the past million years and under pre-anthropogenic climate warming. We show that functional diversity was relatively stable over this period, but underwent significant changes in some key areas of trait space due to changing species abundances.

Draft genome assemblies of four manakins.

Manakins are a family of small suboscine passerine birds characterized by their elaborate courtship displays, non-monogamous mating system, and sexual dimorphism. This family has served as a good model for the study of sexual selection. Here we present genome assemblies of four manakin species, including Cryptopipo holochlora, Dixiphia pipra (also known as Pseudopipra pipra), Machaeropterus deliciosus and Masius chrysopterus, generated by Single-tube Long Fragment Read (stLFR) technology.

Historical specimens and the limits of subspecies phylogenomics in the New World quails (Odontophoridae).

As phylogenomics focuses on comprehensive taxon sampling at the species and population/subspecies levels, incorporating genomic data from historical specimens has become increasingly common. While historical samples can fill critical gaps in our understanding of the evolutionary history of diverse groups, they also introduce additional sources of phylogenomic uncertainty, making it difficult to discern novel evolutionary relationships from artifacts caused by sample quality issues. These problems highlight the need for improved strategies to disentangle artifactual patterns from true biological signal as historical specimens become more prevalent in phylogenomic datasets.

Divergence time estimation of Galliformes based on the best gene shopping scheme of ultraconserved elements.

Background: Divergence time estimation is fundamental to understanding many aspects of the evolution of organisms, such as character evolution, diversification, and biogeography. With the development of sequence technology, improved analytical methods, and knowledge of fossils for calibration, it is possible to obtain robust molecular dating results. However, while phylogenomic datasets show great promise in phylogenetic estimation, the best ways to leverage the large amounts of data for divergence time estimation has not been well explored.

Genomic differentiation in an endemic Philippine genus (Aves: ) owing to geographical isolation on recently disassociated islands.

Phylogeographical studies of Philippine vertebrates have demonstrated that genetic variation is broadly partitioned by Pleistocene island aggregation. Contemporary island discontinuity is expected to influence genetic differentiation but remains relatively undocumented, perhaps because the current episode of island isolation started in relatively recent times. We investigated inter- and intra-island population structure in a Philippine endemic bird genus () to determine whether genetic differentiation has evolved during the recent period of isolation.

When good mitochondria go bad: Cyto-nuclear discordance in landfowl (Aves: Galliformes).

Mitochondrial sequences were among the first molecular data collected for phylogenetic studies and they are plentiful in DNA sequence archives. However, the future value of mitogenomic data in phylogenetics is uncertain, because its phylogenetic signal sometimes conflicts with that of the nuclear genome. A thorough understanding of the causes and prevalence of cyto-nuclear discordance would aid in reconciling different results owing to sequence data type, and provide a framework for interpreting megaphylogenies when taxa which lack substantial nuclear data are placed using mitochondrial data.

A phylogenomic supermatrix of Galliformes (Landfowl) reveals biased branch lengths.

Building taxon-rich phylogenies is foundational for macroevolutionary studies. One approach to improve taxon sampling beyond individual studies is to build supermatricies of publicly available data, incorporating taxa sampled across different studies and utilizing different loci. Most existing supermatrix studies have focused on loci commonly sequenced with Sanger technology ("legacy" markers, such as mitochondrial data and small numbers of nuclear loci).

Phylogenomics of manakins (Aves: Pipridae) using alternative locus filtering strategies based on informativeness.

Target capture sequencing effectively generates molecular marker arrays useful for molecular systematics. These extensive data sets are advantageous where previous studies using a few loci have failed to resolve relationships confidently. Moreover, target capture is well-suited to fragmented source DNA, allowing data collection from species that lack fresh tissues.

Taxonomic evaluation of the Grallaria rufula (Rufous Antpitta) complex (Aves: Passeriformes: Grallariidae) distinguishes sixteen species.

Populations in the Rufous Antpitta (Grallaria rufula) complex occupy humid montane forests of the Andes from northern Colombia and adjacent Venezuela to central Bolivia. Their tawny to cinnamon-colored plumages are generally uniform, featuring subtle variation in hue and saturation across this range. In contrast to their conservative plumage, substantial vocal differences occur among geographically isolated or parapatric populations.

Acknowledging uncertainty in evolutionary reconstructions of ecological niches.

Reconstructing ecological niche evolution can provide insight into the biogeography and diversification of evolving lineages. However, comparative phylogenetic methods may infer the history of ecological niche evolution inaccurately because (a) species' niches are often poorly characterized; and (b) phylogenetic comparative methods rely on niche summary statistics rather than full estimates of species' environmental tolerances. Here, we propose a new framework for coding ecological niches and reconstructing their evolution that explicitly acknowledges and incorporates the uncertainty introduced by incomplete niche characterization.

Earth history and the passerine superradiation.

Avian diversification has been influenced by global climate change, plate tectonic movements, and mass extinction events. However, the impact of these factors on the diversification of the hyperdiverse perching birds (passerines) is unclear because family level relationships are unresolved and the timing of splitting events among lineages is uncertain. We analyzed DNA data from 4,060 nuclear loci and 137 passerine families using concatenation and coalescent approaches to infer a comprehensive phylogenetic hypothesis that clarifies relationships among all passerine families.

Molecular systematics of swifts of the genus Chaetura (Aves: Apodiformes: Apodidae).

Phylogenetic relationships among swifts of the morphologically conservative genus Chaetura were studied using mitochondrial and nuclear DNA sequences. Taxon sampling included all species and 21 of 30 taxa (species and subspecies) within Chaetura. Our results indicate that Chaetura is monophyletic and support the division of the genus into the two subgenera previously identified using plumage characters.

Reconstructing Ecological Niche Evolution When Niches Are Incompletely Characterized.

Evolutionary dynamics of abiotic ecological niches across phylogenetic history can shed light on large-scale biogeographic patterns, macroevolutionary rate shifts, and the relative ability of lineages to respond to global change. An unresolved question is how best to represent and reconstruct evolution of these complex traits at coarse spatial scales through time. Studies have approached this question by integrating phylogenetic comparative methods with niche estimates inferred from correlative and other models.

A genome-wide assessment of stages of elevational parapatry in Bornean passerine birds reveals no introgression: implications for processes and patterns of speciation.

Topographically complex regions often contain the close juxtaposition of closely related species along elevational gradients. The evolutionary causes of these elevational replacements, and thus the origin and maintenance of a large portion of species diversity along elevational gradients, are usually unclear because ecological differentiation along a gradient or secondary contact following allopatric diversification can produce the same pattern. We used reduced representation genomic sequencing to assess genetic relationships and gene flow between three parapatric pairs of closely related songbird taxa ( spiderhunters, leafbirds, and forktails) along an elevational gradient in Borneo.

How do seemingly non-vagile clades accomplish trans-marine dispersal? Trait and dispersal evolution in the landfowl (Aves: Galliformes).

Dispersal ability is a key factor in determining insular distributions and island community composition, yet non-vagile terrestrial organisms widely occur on oceanic islands. The landfowl (pheasants, partridges, grouse, turkeys, quails and relatives) are generally poor dispersers, but the Old World quail () are a notable exception. These birds evolved small body sizes and high-aspect-ratio wing shapes, and hence are capable of trans-continental migrations and trans-oceanic colonization.

Why Do Phylogenomic Data Sets Yield Conflicting Trees? Data Type Influences the Avian Tree of Life more than Taxon Sampling.

Phylogenomics, the use of large-scale data matrices in phylogenetic analyses, has been viewed as the ultimate solution to the problem of resolving difficult nodes in the tree of life. However, it has become clear that analyses of these large genomic data sets can also result in conflicting estimates of phylogeny. Here, we use the early divergences in Neoaves, the largest clade of extant birds, as a "model system" to understand the basis for incongruence among phylogenomic trees.

Historical relationships of three enigmatic phasianid genera (Aves: Galliformes) inferred using phylogenomic and mitogenomic data.

The phylogeny of the Phasianidae (pheasants, partridges, and allies) has been studied extensively. However, these studies have largely ignored three enigmatic genera because of scarce DNA source material and limited overlapping phylogenetic data: blood pheasants (Ithaginis), snow partridges (Lerwa), and long-billed partridges (Rhizothera). Thus, phylogenetic positions of these three genera remain uncertain in what is otherwise a well-resolved phylogeny.