99 research outputs found
Tarphonomus, a new genus of ovenbird (Aves: Passeriformes: Furnariidae) from South America
Tarphonomus, a new genus of ovenbird (Aves: Passeriformes: Furnariidae) from South America, is described. Species included in the new genus, formerly placed in Upucerthia, are T. certhioides and T. harterti
Biogeographic, Ecological, and Evolutionary Aspects of South American Austral Migration, With Special Reference to the Family Tyrannidae.
South American austral migrants are bird species that breed in temperate South America in the southern summer and migrate north, towards or into northern South America, for the southern winter. Austral migration is similar to other avian migration systems in many ways, but its uniquely South American locale is reflected geographically by the relatively short-distance migrations of most austral migrants, and taxonomically by the numerical dominance of the suboscine family Tyrannidae (the tyrant-flycatchers), of which more than 70 species migrate. Detailed examination of the distributions of austral migrant flycatchers revealed that each is to some extent unique, but that discernible general patterns exist. The latitudinal distribution of austral migrant flycatchers seems to be related to that of resident flycatchers, indicating that the same factors are probably affecting both groups, but in different ways. Breeding austral migrant flycatchers are most diverse around the borders of the Gran Chaco, and wintering flycatchers in and around southwestern Amazonia. Most austral migrant tyrannids breed in scrubby or woodland habitats, and breeding and wintering habitats tend to be similar. The Amazonian microhabitats occupied by wintering austral migrant flycatchers also tend to resemble their breeding habitats, rather than the more complex parts of Amazonian rainforest. Climatic factors, especially temperature, play a greater role in the breeding distribution of austral migrant flycatchers than does habitat, consistent with the results of Herrera (1978) for Europe and Willson (1976) for North America. The evolution of passerine austral migration among Neotropical lineages seems to be tied to movement patterns within the tropics, in partial agreement with Levey and Stiles (1992). Austral migrants tend to be drawn from lineages characterized by occupation of canopy, edge, and open habitats and by dietary opportunism; these attributes were likely important evolutionary precursors to temperate-tropical migration
Phylogeny and phylogenetic classification of the antbirds, ovenbirds, woodcreepers, and allies (Aves: Passeriformes: Infraorder Furnariides)
The infraorder Furnariides is a diverse group of suboscine passerine birds comprising a substantial component of the Neotropical avifauna. The included species encompass a broad array of morphologies and behaviours, making them appealing for evolutionary studies, but the size of the group (ca. 600 species) has limited well-sampled higher-level phylogenetic studies. Using DNA sequence data from the nuclear RAG-1 and RAG-2 exons, we undertook a phylogenetic analysis of the Furnariides sampling 124 (more than 88%) of the genera. Basal relationships among family-level taxa differed depending on phylogenetic method, but all topologies had little nodal support, mirroring the results from earlier studies in which discerning relationships at the base of the radiation was also difficult. In contrast, branch support for family-rank taxa and for many relationships within those clades was generally high. Our results support the Melanopareidae and Grallariidae as distinct from the Rhinocryptidae and Formicariidae, respectively. Within the Furnariides our data contradict some recent phylogenetic hypotheses and suggest that further study is needed to resolve these discrepancies. Of the few genera represented by multiple species, several were not monophyletic, indicating that additional systematic work remains within furnariine families and must include dense taxon sampling. We use this study as a basis for proposing a new phylogenetic classification for the group and in the process erect new family-group names for clades having high branch support across methods. © 2009 The Willi Hennig Society
Integrating Sequence Capture and Restriction Site-Associated DNA Sequencing to resolve Recent Radiations of Pelagic Seabirds
The diversification of modern birds has been shaped by a number of radiations. Rapid diversification events make reconstructing the evolutionary relationships among taxa challenging due to the convoluted effects of incomplete lineage sorting (ILS) and introgression. Phylogenomic datasets have the potential to detect patterns of phylogenetic incongruence, and to address their causes. However, the footprints of ILS and introgression on sequence data can vary between different phylogenomic markers at different phylogenetic scales depending on factors such as their evolutionary rates or their selection pressures. We show that combining phylogenomic markers that evolve at different rates, such as paired-end double-digest restriction site-associated DNA (PE-ddRAD) and ultraconserved elements (UCEs), allows a comprehensive exploration of the causes of phylogenetic discordance associated with short internodes at different timescales. We used thousands of UCE and PE-ddRAD markers to produce the first well-resolved phylogeny of shearwaters, a group of medium-sized pelagic seabirds that are among the most phylogenetically controversial and endangered bird groups. We found that phylogenomic conflict was mainly derived from high levels of ILS due to rapid speciation events. We also documented a case of introgression, despite the high philopatry of shearwaters to their breeding sites, which typically limits gene flow. We integrated state-of-the-art concatenated and coalescent-based approaches to expand on previous comparisons of UCE and RAD-Seq datasets for phylogenetics, divergence time estimation and inference of introgression, and we propose a strategy to optimise RAD-Seq data for phylogenetic analyses. Our results highlight the usefulness of combining phylogenomic markers evolving at different rates to understand the causes of phylogenetic discordance at different timescales
Lineage diversification and morphological evolution in a large-scale continental radiation: The neotropical ovenbirds and woodcreepers (aves: furnariidae)
Patterns of diversification in species-rich clades provide insight into the processes that generate biological diversity. We tested different models of lineage and phenotypic diversification in an exceptional continental radiation, the ovenbird family Furnariidae, using the most complete species-level phylogenetic hypothesis produced to date for a major avian clade (97% of 293 species). We found that the Furnariidae exhibit nearly constant rates of lineage accumulation but show evidence of constrained morphological evolution. This pattern of sustained high rates of speciation despite limitations on phenotypic evolution contrasts with the results of most previous studies of evolutionary radiations, which have found a pattern of decelerating diversity-dependent lineage accumulation coupled with decelerating or constrained phenotypic evolution. Our results suggest that lineage accumulation in tropical continental radiations may not be as limited by ecological opportunities as in temperate or island radiations. More studies examining patterns of both lineage and phenotypic diversification are needed to understand the often complex tempo and mode of evolutionary radiations on continents. © 2011 The Author(s). Evolution © 2011 The Society for the Study of Evolution
Palaeoceanographic changes in the late Pliocene promoted rapid diversification in pelagic seabirds
Aim: Palaeoceanographic changes can act as drivers of diversification and speciation, even in highly mobile marine organisms. Shearwaters are a group of globally distributed and highly mobile pelagic seabirds. Despite a recent well-resolved phylogeny, shearwaters have controversial species limits, and show periods of both slow and rapid diversification. Here, we explore the role of palaeoceanographic changes on shearwaters' diversification and speciation. We investigate shearwater biogeography and the evolution of a key phenotypic trait, body size, and we assess the validity of their current taxonomy
FORTY-EIGHTH SUPPLEMENT TO THE AMERICAN ORNITHOLOGISTS’ UNION CHECK-LIST OF NORTH AMERICAN BIRDS
Sixty-first Supplement to the American Ornithological Society\u27s Check-list of North American Birds
A Phylogenomic Supertree of Birds
It has long been appreciated that analyses of genomic data (e.g., whole genome sequencing or sequence capture) have the potential to reveal the tree of life, but it remains challenging to move from sequence data to a clear understanding of evolutionary history, in part due to the computational challenges of phylogenetic estimation using genome-scale data. Supertree methods solve that challenge because they facilitate a divide-and-conquer approach for large-scale phylogeny inference by integrating smaller subtrees in a computationally efficient manner. Here, we combined information from sequence capture and whole-genome phylogenies using supertree methods. However, the available phylogenomic trees had limited overlap so we used taxon-rich (but not phylogenomic) megaphylogenies to weave them together. This allowed us to construct a phylogenomic supertree, with support values, that included 707 bird species (~7% of avian species diversity). We estimated branch lengths using mitochondrial sequence data and we used these branch lengths to estimate divergence times. Our time-calibrated supertree supports radiation of all three major avian clades (Palaeognathae, Galloanseres, and Neoaves) near the Cretaceous-Paleogene (K-Pg) boundary. The approach we used will permit the continued addition of taxa to this supertree as new phylogenomic data are published, and it could be applied to other taxa as well
Conflict between Genetic and Phenotypic Differentiation: The Evolutionary History of a ‘Lost and Rediscovered’ Shorebird
Understanding and resolving conflicts between phenotypic and genetic differentiation is central to evolutionary research. While phenotypically monomorphic species may exhibit deep genetic divergences, some morphologically distinct taxa lack notable genetic differentiation. Here we conduct a molecular investigation of an enigmatic shorebird with a convoluted taxonomic history, the White-faced Plover (Charadrius alexandrinus dealbatus), widely regarded as a subspecies of the Kentish Plover (C. alexandrinus). Described as distinct in 1863, its name was consistently misapplied in subsequent decades until taxonomic clarification ensued in 2008. Using a recently proposed test of species delimitation, we reconfirm the phenotypic distinctness of dealbatus. We then compare three mitochondrial and seven nuclear DNA markers among 278 samples of dealbatus and alexandrinus from across their breeding range and four other closely related plovers. We fail to find any population genetic differentiation between dealbatus and alexandrinus, whereas the other species are deeply diverged at the study loci. Kentish Plovers join a small but growing list of species for which low levels of genetic differentiation are accompanied by the presence of strong phenotypic divergence, suggesting that diagnostic phenotypic characters may be encoded by few genes that are difficult to detect. Alternatively, gene expression differences may be crucial in producing different phenotypes whereas neutral differentiation may be lagging behind
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