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Not AvailableThis study investigates the evolution of locomotory morphology and migratory behavior in nightingale-thrushes (genus Catharus), a clade of songbirds with diverse migratory strategies. With large datasets of molecular and morphometric characters, we resolve phylogenetic relationships, identify and model migration-related morphological characters, and estimate ancestral states of those characters to infer evolutionary transitions in the migratory phenotype. While acknowledging that unknown factors (e.g., differential extinction) may confound interpretation, our results suggest that (1) migratory behavior and its functional morphology are fundamentally linked; (2) short-distance or elevational migration (not long-distance) was the ancestral state of Catharus; (3) short-distance migration was the evolutionary precursor of long-distance migration; and (4) the short-distance migrant, Hermit Thrush (C. guttatus), may be in relative phenotypic (ecological) stasis. This potentially explains the ecological incumbency of C. guttatus in temperate North America during winter, and offers a new framework for interpreting the evolutionary sequence that produced long-distance migration in this model system. 

This paper provides a catalogue of the type specimens of lice (Insecta: Psocodea: Phthiraptera) held in the collection of the Field Museum of Natural History (FMNH), Chicago, Illinois, USA. There are 178 nominal species, four of which are represented by holotype only; 14 by holotype, allotype and paratypes; 29 by holotype and paratypes; 127 by paratypes only; three by neoparatypes, and one by paralectotype. The main goal of this type catalog is to make the louse type specimens and their metadata more readily available to biodiversity researchers. 

Abstract We reconstruct the species-level phylogenetic relationship among toucans, toucan-barbets, New World barbets using phylogenomic data to assess the monophyly and relationships at the family, generic, and specific levels. Our analyses confirmed (1) the monophyly of toucans (Aves: Ramphastidae), toucan-barbets (Aves: Semnornithidae), and New World barbets (Aves: Capitonidae) and that the toucan-barbets are sister to the toucans, an arrangement suggested, but poorly supported, in previously published phylogenies; (2) the paraphyly of lowland Selenidera toucanets with respect to Andigena mountain-toucans; and (3) evidence of some mitonuclear discordance, suggesting introgression or incomplete lineage sorting. For example, mitonuclear conflict in the phylogenetic placement of Ramphastos vitellinus subspecies suggests that Amazonian populations of Ramphastos vitellinus ariel may have introgressed mitogenomes derived from other Amazonian vitellinus taxa. To reconstruct the phylogenetic history of toucans, toucan-barbets, and New World barbets, we included all species-level taxa from the three families, with the addition of outgroups from the two major clades of Old World barbets (Megalaimidae and Lybiidae). We analyzed a combination of UCE sequences and whole mitochondrial genome sequences to reconstruct phylogenetic trees. 

Abstract MyrsideaWaterston is the most diverse genus of chewing lice, primarily parasitizing perching birds (Passeriformes), which is the most speciose avian order.Myrsideaalso parasitize several hosts from non‐passerine groups, including toucans, barbets, woodpeckers (Piciformes) and hummingbirds (Apodiformes). To examine host specificity, host switching and generic limits, we reconstructed a phylogeny of the avian feather louse genusMyrsideausing DNA sequence data from two fragments of the mitochondrial COI gene and a fragment of the nuclear EF‐1α gene for 152Myrsideaspecimens collected from 23 avian host families. Unlike other highly diverse louse genera, only a small proportion ofMyrsideaspecies parasitize more than one host species. We found that host family has significant phylogenetic signal on theMyrsideaphylogeny. These results suggest thatMyrsideais generally highly host‐specific, with some exceptions where host switching is important. We found that there are two separate groups ofMyrsideathat parasitize toucans, and that both are nested withinMyrsideafound on perching birds, suggesting that these toucan ectoparasites may have arisen from two independent host switching events. Lastly, representatives of the genusRamphasticolaCarriker, which was originally described as a distinct genus due to a suite of morphologically unique characters, falls in with a strongly supported clade ofMyrsideaparasitizingRamphastostoucans, and therefore we definitively placeRamphasticolaas a synonym ofMyrsidea. 

Abstract AimMacroecological analyses provide valuable insights into factors that influence how parasites are distributed across space and among hosts. Amid large uncertainties that arise when generalizing from local and regional findings, hierarchical approaches applied to global datasets are required to determine whether drivers of parasite infection patterns vary across scales. We assessed global patterns of haemosporidian infections across a broad diversity of avian host clades and zoogeographical realms to depict hotspots of prevalence and to identify possible underlying drivers. LocationGlobal. Time period1994–2019. Major taxa studiedAvian haemosporidian parasites (generaPlasmodium,Haemoproteus,LeucocytozoonandParahaemoproteus). MethodsWe amalgamated infection data from 53,669 individual birds representing 2,445 species world‐wide. Spatio‐phylogenetic hierarchical Bayesian models were built to disentangle potential landscape, climatic and biotic drivers of infection probability while accounting for spatial context and avian host phylogenetic relationships. ResultsIdiosyncratic responses of the three most common haemosporidian genera to climate, habitat, host relatedness and host ecological traits indicated marked variation in host infection rates from local to global scales. Notably, host ecological drivers, such as migration distance forPlasmodiumandParahaemoproteus, exhibited predominantly varying or even opposite effects on infection rates across regions, whereas climatic effects on infection rates were more consistent across realms. Moreover, infections in some low‐prevalence realms were disproportionately concentrated in a few local hotspots, suggesting that regional‐scale variation in habitat and microclimate might influence transmission, in addition to global drivers. Main conclusionsOur hierarchical global analysis supports regional‐scale findings showing the synergistic effects of landscape, climate and host ecological traits on parasite transmission for a cosmopolitan and diverse group of avian parasites. Our results underscore the need to account for such interactions, in addition to possible variation in drivers across regions, to produce the robust inference required to predict changes in infection risk under future scenarios.