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1.
Mol Phylogenet Evol ; 197: 108085, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38688441

RESUMO

AIM: We aim to determine the evolutionary origins and population genetics of mallard-like ducks of Oceania, greater Indonesia, and the Philippines. LOCATION: Oceania, greater Indonesia, and the Philippines. TAXON: Mallard (Anas platyrhynchos), Pacific black duck (A. superciliosa spp.), and Philippine duck (A. luzonica) METHODS: Thousands of nuclear ddRAD-seq loci and the mitochondrial DNA control region were assayed across individuals representative of each species' range. We assessed population structure and phylogenetic relationships, as well as estimated demographic histories to reconstruct the biogeographical history of each species. RESULTS: Philippine and Pacific black ducks represent unique genetic lineages that diverged from the mallard 1-2 million years ago. We find no support for the Philippine duck representing a hybrid species as once posited; however, their low levels of genetic diversity requires further attention. We find a lack of substructure among Philippine ducks. However, we found pronounced differentiation between subspecies of Pacific black ducks, especially between A. s. superciliosa from New Zealand and A. s. rogersi from Australia, Papua New Guinea, and Timor-Leste, Indonesia. Anas superciliosa pelewensis gave mixed results; individuals from the Solomon Islands were differentiated from the other subspecies, but those from the island of Aunu'u, American Samoa, were genetically more similar to A. s. rogersi than A. s. pelewensis samples from the Solomon Islands. Finally, we find limited evidence of interspecific gene flow at evolutionary scales, and mallard introgression among contemporary samples. MAIN CONCLUSIONS: Mallard-like ducks radiated across Oceania, greater Indonesia, and the Philippines within the last 2 million years. Only the Pacific black duck showed unique sub-structuring that largely followed known sub-species ranges, except for A. s. pelewensis. We posit that the high interrelatedness among Solomon Island samples suggests that their genetic distinctiveness may simply be the result of high levels of genetic drift. In contrast, we conclude that mainland Australian Pacific black ducks were the most likely source for the recent colonization of American Samoa. As a result, our findings suggest that either the A. s. pelewensis subspecies designations and/or its geographical range may require re-evaluation. Continued re-evaluation of evolutionary and taxonomic relationships is necessary when attempting to reconstruct and understand biogeographical histories, with important implications towards any attempts to implement conservation strategies.


Assuntos
DNA Mitocondrial , Patos , Filogenia , Animais , Patos/genética , Patos/classificação , Filipinas , Indonésia , DNA Mitocondrial/genética , Genética Populacional , Oceania , Variação Genética , Análise de Sequência de DNA , Evolução Biológica , Filogeografia
2.
Syst Biol ; 72(1): 228-241, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35916751

RESUMO

Gene tree discordance is expected in phylogenomic trees and biological processes are often invoked to explain it. However, heterogeneous levels of phylogenetic signal among individuals within data sets may cause artifactual sources of topological discordance. We examined how the information content in tips and subclades impacts topological discordance in the parrots (Order: Psittaciformes), a diverse and highly threatened clade of nearly 400 species. Using ultraconserved elements from 96% of the clade's species-level diversity, we estimated concatenated and species trees for 382 ingroup taxa. We found that discordance among tree topologies was most common at nodes dating between the late Miocene and Pliocene, and often at the taxonomic level of the genus. Accordingly, we used two metrics to characterize information content in tips and assess the degree to which conflict between trees was being driven by lower-quality samples. Most instances of topological conflict and nonmonophyletic genera in the species tree could be objectively identified using these metrics. For subclades still discordant after tip-based filtering, we used a machine learning approach to determine whether phylogenetic signal or noise was the more important predictor of metrics supporting the alternative topologies. We found that when signal favored one of the topologies, the noise was the most important variable in poorly performing models that favored the alternative topology. In sum, we show that artifactual sources of gene tree discordance, which are likely a common phenomenon in many data sets, can be distinguished from biological sources by quantifying the information content in each tip and modeling which factors support each topology. [Historical DNA; machine learning; museomics; Psittaciformes; species tree.].


Assuntos
Papagaios , Humanos , Animais , Filogenia , Papagaios/genética
3.
Mol Ecol ; 32(17): 4844-4862, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37515525

RESUMO

Many organisms possess multiple discrete genomes (i.e. nuclear and organellar), which are inherited separately and may have unique and even conflicting evolutionary histories. Phylogenetic reconstructions from these discrete genomes can yield different patterns of relatedness, a phenomenon known as cytonuclear discordance. In many animals, mitonuclear discordance (i.e. discordant evolutionary histories between the nuclear and mitochondrial genomes) has been widely documented, but its causes are often considered idiosyncratic and inscrutable. We show that a case of mitonuclear discordance in Todiramphus kingfishers can be explained by extensive genome-wide incomplete lineage sorting (ILS), likely a result of the explosive diversification history of this genus. For these kingfishers, quartet frequencies reveal that the nuclear genome is dominated by discordant topologies, with none of the internal branches in our consensus nuclear tree recovered in >50% of genome-wide gene trees. Meanwhile, a lack of inter-species shared ancestry, non-significant pairwise tests for gene flow, and little evidence for meaningful migration edges between species, leads to the conclusion that gene flow cannot explain the mitonuclear discordance we observe. This lack of evidence for gene flow combined with evidence for extensive genome-wide gene tree discordance, a hallmark of ILS, leads us to conclude that the mitonuclear discordance we observe likely results from ILS, specifically deep coalescence of the mitochondrial genome. Based on this case study, we hypothesize that similar demographic histories in other 'great speciator' taxa across the Indo-Pacific likely predispose these groups to high levels of ILS and high likelihoods of mitonuclear discordance.


Assuntos
Fluxo Gênico , Genoma Mitocondrial , Animais , Filogenia , Genoma Mitocondrial/genética , Núcleo Celular/genética , Aves/genética
4.
Mol Ecol ; 31(19): 5060-5073, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35949055

RESUMO

Plumage divergence can function as a strong premating barrier when species come into secondary contact. When it fails to do so, the results are often genome homogenization and phenotypic hybrids at the zone of contact. This is not the case in the largely sympatric masked woodswallow and white-browed woodswallow species (Passeriformes: Artamidae: Artamus spp) complex in Australia where phenotypic integrity is sustained despite no discernible mitochondrial structure in earlier work. This lack of structure may suggest recent divergence, ongoing gene flow or both, and phenotypic hybrids are reported albeit rarely. Here, we further assessed the population structure and differentiation across the species' nuclear genomes using ddRAD-seq. As found in the mitochondrial genome, no structure or divergence within or between the two species was detected in the nuclear genome. This coarse sampling of the genome nonetheless revealed peaks of differentiation around the genes SOX5 and AXIN1. Both are involved in the Wnt/ß-catenin signalling pathway, which regulates feather development. Reconstruction of demographic history and estimation of parameters supports a scenario of secondary contact. Our study informs how divergent plumage morphs may arise and be sustained despite whole-genome homogenization and reveals new candidate genes potentially involved in plumage divergence.


Assuntos
Passeriformes , Simpatria , Animais , Austrália , Fluxo Gênico , Especiação Genética , Genômica , Passeriformes/genética , beta Catenina/genética
5.
Mol Phylogenet Evol ; 168: 107379, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34965464

RESUMO

The utility of islands as natural laboratories of evolution is exemplified in the patterns of differentiation in widespread, phenotypically variable lineages. The whistlers (Aves: Pachycephalidae) are one of the most complex avian radiations, with a combination of widespread and locally endemic taxa spanning the vast archipelagos of the Indo-Pacific, making them an ideal group to study patterns and processes of diversification on islands. Here, we present a robust, species-level phylogeny of all five genera and 85% of species within Pachycephalidae, based on thousands of ultraconserved elements (UCEs) generated with a target-capture approach and high-throughput sequencing. We clarify phylogenetic relationships within Pachycephala and report on divergence timing and ancestral range estimation. We explored multiple biogeographic coding schemes that incorporated geological uncertainty in this complex region. The biogeographic origin of this group was difficult to discern, likely owing to aspects of dynamic Earth history in the Indo-Pacific. The Australo-Papuan region was the likely origin of crown-group whistlers, but the specific ancestral area could not be identified more precisely than Australia or New Guinea, and Wallacea may have played a larger role than previously realized in the evolutionary history of whistlers. Multiple independent colonizations of island archipelagos across Melanesia, Wallacea, and the Philippines contributed to the relatively high species richness of extant whistlers. This work refines our understanding of one of the regions' most celebrated bird lineages and adds to our growing knowledge about the patterns and processes of diversification in the Indo-Pacific.


Assuntos
Passeriformes , Animais , Austrália , Melanesia , Passeriformes/genética , Filipinas , Filogenia , Filogeografia
6.
Mol Phylogenet Evol ; 166: 107333, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34688879

RESUMO

Chalcophaps is a morphologically conserved genus of ground-walking doves distributed from India to mainland China, south to Australia, and across the western Pacific to Vanuatu. Here, we reconstruct the evolutionary history of this genus using DNA sequence data from two nuclear genes and one mitochondrial gene, sampled from throughout the geographic range of Chalcophaps. We find support for three major evolutionary lineages in our phylogenetic reconstruction, each corresponding to the three currently recognized Chalcophaps species. Despite this general concordance, we identify discordant mitochondrial and nuclear ancestries in the subspecies C. longirostris timorensis, raising further questions about the evolutionary history of this Timor endemic population. Within each of the three species, we find evidence for isolation by distance or hierarchical population structure, indicating an important role for geography in the diversification of this genus. Despite being distributed broadly across a highly fragmented geographic region known as a hotspot for avian diversification, the Chalcophaps doves show modest levels of phenotypic and genetic diversity, a pattern potentially explained by strong population connectivity owing to high overwater dispersal capability.


Assuntos
Columbidae , DNA Mitocondrial , Animais , Columbidae/genética , DNA Mitocondrial/química , DNA Mitocondrial/genética , Variação Genética , Filogenia , Filogeografia
7.
Proc Natl Acad Sci U S A ; 116(16): 7916-7925, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30936315

RESUMO

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. Then, we calibrated this phylogeny using 13 fossils to examine the effects of different events in Earth history on the timing and rate of passerine diversification. Our analyses reconcile passerine diversification with the fossil and geological records; suggest that passerines originated on the Australian landmass ∼47 Ma; and show that subsequent dispersal and diversification of passerines was affected by a number of climatological and geological events, such as Oligocene glaciation and inundation of the New Zealand landmass. Although passerine diversification rates fluctuated throughout the Cenozoic, we find no link between the rate of passerine diversification and Cenozoic global temperature, and our analyses show that the increases in passerine diversification rate we observe are disconnected from the colonization of new continents. Taken together, these results suggest more complex mechanisms than temperature change or ecological opportunity have controlled macroscale patterns of passerine speciation.


Assuntos
Passeriformes , Animais , Austrália , Biodiversidade , Evolução Biológica , Fósseis , Nova Zelândia , Passeriformes/classificação , Passeriformes/genética , Passeriformes/fisiologia , Filogenia
8.
Mol Ecol ; 30(9): 2087-2103, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33615597

RESUMO

Hybridization, introgression, and reciprocal gene flow during speciation, specifically the generation of mitonuclear discordance, are increasingly observed as parts of the speciation process. Genomic approaches provide insight into where, when, and how adaptation operates during and after speciation and can measure historical and modern introgression. Whether adaptive or neutral in origin, hybridization can cause mitonuclear discordance by placing the mitochondrial genome of one species (or population) in the nuclear background of another species. The latter, introgressed species may eventually have its own mtDNA replaced or "captured" by other species across its entire geographical range. Intermediate stages in the capture process should be observable. Two nonsister species of Australasian monarch-flycatchers, Spectacled Monarch (Symposiachrus trivirgatus) mostly of Australia and Indonesia and Spot-winged Monarch (S. guttula) of New Guinea, present an opportunity to observe this process. We analysed thousands of single nucleotide polymorphisms (SNPs) derived from ultraconserved elements of all subspecies of both species. Mitochondrial DNA sequences of Australian populations of S. trivirgatus form two paraphyletic clades, one being sister to and presumably introgressed by S. guttula despite little nuclear signal of introgression. Population genetic analyses (e.g., tests for modern and historical gene flow and selection) support at least one historical gene flow event between S. guttula and Australian S. trivirgatus. We also uncovered introgression from the Maluku Islands subspecies of S. trivirgatus into an island population of S. guttula, resulting in apparent nuclear paraphyly. We find that neutral demographic processes, not adaptive introgression, are the most likely cause of these complex population histories. We suggest that a Pleistocene extinction of S. guttula from mainland Australia resulted from range expansion by S. trivirgatus.


Assuntos
Fluxo Gênico , Passeriformes , Animais , Austrália , DNA Mitocondrial/genética , Hibridização Genética , Indonésia , Ilhas , Nova Guiné , Passeriformes/genética , Filogenia
9.
Syst Biol ; 69(5): 820-829, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32415976

RESUMO

The bowerbirds in New Guinea and Australia include species that build the largest and perhaps most elaborately decorated constructions outside of humans. The males use these courtship bowers, along with their displays, to attract females. In these species, the mating system is polygynous and the females alone incubate and feed the nestlings. The bowerbirds also include 10 species of the socially monogamous catbirds in which the male participates in most aspects of raising the young. How the bower-building behavior evolved has remained poorly understood, as no comprehensive phylogeny exists for the family. It has been assumed that the monogamous catbird clade is sister to all polygynous species. We here test this hypothesis using a newly developed pipeline for obtaining homologous alignments of thousands of exonic and intronic regions from genomic data to build a phylogeny. Our well-supported species tree shows that the polygynous, bower-building species are not monophyletic. The result suggests either that bower-building behavior is an ancestral condition in the family that was secondarily lost in the catbirds, or that it has arisen in parallel in two lineages of bowerbirds. We favor the latter hypothesis based on an ancestral character reconstruction showing that polygyny but not bower-building is ancestral in bowerbirds, and on the observation that Scenopoeetes dentirostris, the sister species to one of the bower-building clades, does not build a proper bower but constructs a court for male display. This species is also sexually monomorphic in plumage despite having a polygynous mating system. We argue that the relatively stable tropical and subtropical forest environment in combination with low predator pressure and rich food access (mostly fruit) facilitated the evolution of these unique life-history traits. [Adaptive radiation; bowerbirds; mating system, sexual selection; whole genome sequencing.].


Assuntos
Evolução Biológica , Aves/classificação , Aves/fisiologia , Comportamento de Nidação , Filogenia , Animais
10.
Heredity (Edinb) ; 125(3): 167, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32694588

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

11.
Heredity (Edinb) ; 125(3): 85-100, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32398870

RESUMO

Advances in sequencing technologies have revolutionized wildlife conservation genetics. Analysis of genomic data sets can provide high-resolution estimates of genetic structure, genetic diversity, gene flow, and evolutionary history. These data can be used to characterize conservation units and to effectively manage the genetic health of species in a broad evolutionary context. Here we utilize thousands of genome-wide single-nucleotide polymorphisms (SNPs) and mitochondrial DNA to provide the first genetic assessment of the Australian red-tailed black-cockatoo (Calyptorhynchus banksii), a widespread bird species comprising populations of varying conservation concern. We identified five evolutionarily significant units, which are estimated to have diverged during the Pleistocene. These units are only partially congruent with the existing morphology-based subspecies taxonomy. Genetic clusters inferred from mitochondrial DNA differed from those based on SNPs and were less resolved. Our study has a range of conservation and taxonomic implications for this species. In particular, we provide advice on the potential genetic rescue of the Endangered and restricted-range subspecies C. b. graptogyne, and propose that the western C. b. samueli population is diagnosable as a separate subspecies. The results of our study highlight the utility of considering the phylogeographic relationships inferred from genome-wide SNPs when characterizing conservation units and management priorities, which is particularly relevant as genomic data sets become increasingly accessible.


Assuntos
Cacatuas , Genética Populacional , Filogeografia , Animais , Austrália , Cacatuas/genética , Conservação dos Recursos Naturais , DNA Mitocondrial , Espécies em Perigo de Extinção , Variação Genética , Filogenia , Polimorfismo de Nucleotídeo Único
12.
Biol Lett ; 16(5): 20200040, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32396783

RESUMO

Wallace's Line demarcates the transition between the differentiated regional faunas of Asia and Australia. However, while patterns of biotic differentiation across these two continental landmasses and the intervening island groups (Wallacea) have been extensively studied, patterns of long-term dispersal and diversification across this region are less well understood. Frogmouths (Aves: Podargidae) are a relictual family of large nocturnal birds represented by three extant genera occurring, respectively, in Asia, 'Sahul' (Australia and New Guinea) and the Solomon Islands, thus spanning Wallace's Line. We used new mitochondrial genomes from each of the extant frogmouth genera to estimate the timeline of frogmouth evolution and dispersal across Wallace's Line. Our results suggest that the three genera diverged and dispersed during the mid-Cenozoic between approximately 30 and 40 Mya. These divergences are among the oldest inferred for any trans-Wallacean vertebrate lineage. In addition, our results reveal that the monotypic Solomons frogmouth (Rigidipenna inexpectata) is one of the most phylogenetically divergent endemic bird lineages in the southwest Pacific. We suggest that the contemporary distribution of exceptionally deep divergences among extant frogmouth lineages may be explained by colonization of, and subsequent long-term persistence on, island arcs in the southwest Pacific during the Oligocene. These island arcs may have provided a pathway for biotic dispersal out of both Asia and Australia that preceded the formation of extensive emergent landmasses in Wallacea by at least 10 million years.


Assuntos
Aves , Animais , Ásia , Austrália , Ilhas , Nova Guiné , Filogenia
13.
Pain Med ; 21(Suppl 2): S62-S72, 2020 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-33313728

RESUMO

BACKGROUND: Coordinated efforts between the National Institutes of Health, the Department of Defense, and the Department of Veterans Affairs have built the capacity for large-scale clinical research investigating the effectiveness of nonpharmacologic pain treatments. This is an encouraging development; however, what constitutes best practice for nonpharmacologic management of low back pain (LBP) is largely unknown. DESIGN: The Improving Veteran Access to Integrated Management of Back Pain (AIM-Back) trial is an embedded pragmatic cluster-randomized trial that will examine the effectiveness of two different care pathways for LBP. Sixteen primary care clinics will be randomized 1:1 to receive training in delivery of 1) an integrated sequenced-care pathway or 2) a coordinated pain navigator pathway. Primary outcomes are pain interference and physical function (Patient-Reported Outcomes Measurement Information System Short Form [PROMIS-SF]) collected in the electronic health record at 3 months (n=1,680). A subset of veteran participants (n=848) have consented to complete additional surveys at baseline and at 3, 6, and 12 months for supplementary pain and other measures. SUMMARY: AIM-Back care pathways will be tested for effectiveness, and treatment heterogeneity will be investigated to identify which veterans may respond best to a given pathway. Health care utilization patterns (including opioid use) will also be compared between care pathways. Therefore, the AIM-Back trial will provide important information that can inform the future delivery of nonpharmacologic treatment of LBP.


Assuntos
Dor Lombar , Veteranos , Humanos , Dor Lombar/terapia , Manejo da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários , Fatores de Tempo
14.
Proc Biol Sci ; 286(1916): 20192258, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31771472

RESUMO

The observed variation in the body size responses of endotherms to climate change may be explained by two hypotheses: the size increases with climate variability (the starvation resistance hypothesis) and the size shrinks as mean temperatures rise (the heat exchange hypothesis). Across 82 Australian passerine species over 50 years, shrinking was associated with annual mean temperature rise exceeding 0.012°C driven by rising winter temperatures for arid and temperate zone species. We propose the warming winters hypothesis to explain this response. However, where average summer temperatures exceeded 34°C, species experiencing annual rise over 0.0116°C tended towards increasing size. Results suggest a broad-scale physiological response to changing climate, with size trends probably reflecting the relative strength of selection pressures across a climatic regime. Critically, a given amount of temperature change will have varying effects on phenotype depending on the season in which it occurs, masking the generality of size patterns associated with temperature change. Rather than phenotypic plasticity, and assuming body size is heritable, results suggest selective loss or gain of particular phenotypes could generate evolutionary change but may be difficult to detect with current warming rates.


Assuntos
Tamanho Corporal/fisiologia , Aves Canoras/fisiologia , Adaptação Fisiológica , Animais , Austrália , Evolução Biológica , Mudança Climática , Fenótipo , Estações do Ano , Temperatura
15.
Mol Ecol ; 28(3): 630-643, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30561150

RESUMO

Genome divergence is greatly influenced by gene flow during early stages of speciation. As populations differentiate, geographic barriers can constrain gene flow and so affect the dynamics of divergence and speciation. Current geography, specifically disjunction and continuity of ranges, is often used to predict the historical gene flow during the divergence process. We test this prediction in eight meliphagoid bird species complexes codistributed in four regions. These regions are separated by known biogeographical barriers across northern Australia and Papua New Guinea. We find that bird populations currently separated by terrestrial habitat barriers within Australia and marine barriers between Australia and Papua New Guinea have a range of divergence levels and probability of gene flow not associated with current range connectivity. Instead, geographic distance and historical range connectivity better predict divergence and probability of gene flow. In this dynamic environmental context, we also find support for a nonlinear decrease of the probability of gene flow during the divergence process. The probability of gene flow initially decreases gradually after a certain level of divergence is reached. Its decrease then accelerates until the probability is close to zero. This implies that although geographic connectivity may have more of an effect early in speciation, other factors associated with higher divergence may play a more important role in influencing gene flow midway through and later in speciation. Current geographic connectivity may then mislead inferences regarding potential for gene flow during speciation under a complex and dynamic history of geographic and reproductive isolation.


Assuntos
Aves/genética , Fluxo Gênico , Especiação Genética , Genética Populacional , Animais , Austrália , DNA Mitocondrial/genética , Geografia , Modelos Genéticos , Papua Nova Guiné , Polimorfismo de Nucleotídeo Único , Isolamento Reprodutivo
16.
Mol Phylogenet Evol ; 131: 48-54, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30367975

RESUMO

Australo-Pacific Petroica robins are known for their striking variability in sexual plumage coloration. Molecular studies in recent years have revised the taxonomy of species and subspecies boundaries across the southwest Pacific and New Guinea. However, these studies have not been able to resolve phylogenetic relationships within Petroica owing to limited sampling of the nuclear genome. Here, we sequence five nuclear introns across all species for which fresh tissue was available. Nuclear loci offer support for major geographic lineages that were first inferred from mtDNA. We find almost no shared nuclear alleles between currently recognized species within the New Zealand and Australian lineages, whereas the Pacific robin radiation has many shared alleles. Multilocus coalescent species trees based on nuclear loci support a sister relationship between the Australian lineage and the Pacific robin radiation-a node that is poorly supported by mtDNA. We also find discordance in support for a sister relationship between the similarly plumaged Rose Robin (P. rosea) and Pink Robin (P. rodinogaster). Our nuclear data complement previous mtDNA studies in suggesting that the phenotypically cryptic eastern and western populations of Australia's Scarlet Robin (P. boodang) are genetically distinct lineages at the early stages of divergence and speciation.


Assuntos
Núcleo Celular/genética , Variação Genética , Íntrons/genética , Aves Canoras/genética , Animais , Austrália , DNA Mitocondrial/genética , Feminino , Masculino , Oceano Pacífico , Filogenia , Filogeografia , Caracteres Sexuais , Especificidade da Espécie
17.
Mol Phylogenet Evol ; 137: 200-209, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30914395

RESUMO

Old World orioles (Oriolidae) are medium-sized passerine birds confined largely to forested areas of Africa, Eurasia and Australasia. We present a new complete molecular (mtDNA) subspecies level phylogeny of the Oriolidae including all 113 taxa (35 species) together with a backbone phylogeny of 19 taxa from the main Oriolus clades based on (i) 21 nuclear genes, (ii) whole mito-genomes, and (iii) genome-wide ultraconserved elements. We use this phylogeny to assess systematic relationships and the biogeographical history of this avian family. Furthermore, we use morphological measurements to investigate the relationship between size and shape axes and upstream or back-colonization of this extensive island region from Asia. We show that several subspecies or groups of subspecies may warrant species rank and we find a continental example of two morphologically distinct species (O. mellianus/O. traillii) being genetically (mtDNA) very similar. Biogeographically, we confirm previous findings that members of the Oriolidae originated in Australo-Papua. Dispersal out of this area took place around 15 Mya to southeast Asia and Africa, and from Africa to the Palearctic followed by recolonization of the Indonesian and Philippine island region during the Plio-Pleistocene. Recolonisation of the Indonesian and Philippine islands coincided with an increase in body size, which may have facilitated the ability to co-exist with other congenerics.


Assuntos
Passeriformes/classificação , Filogenia , Animais , Australásia , DNA Mitocondrial/genética , Funções Verossimilhança , Passeriformes/genética , Especificidade da Espécie , Fatores de Tempo
18.
Heredity (Edinb) ; 122(4): 402-416, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30082918

RESUMO

The study of hybrid zones advances understanding of the speciation process, and approaches incorporating genomic data are increasingly used to draw significant conclusions about the impact of hybridisation. Despite the progress made, the complex interplay of factors that can lead to substantially variable hybridisation outcomes are still not well understood, and many systems and/or groups remain comparatively poorly studied. Our study aims to broaden the literature on avian hybrid zones, investigating a potentially geographically and temporally complex putative hybrid zone between two native Australian non-sister parrot species, the pale-headed and eastern rosellas (Platycercus adscitus and Platycercus eximius, respectively). We analysed six plumage traits and >1400 RADseq loci and detected hybrid individuals and an unexpectedly complex geographic structure. The hybrid zone is larger than previously described due to either observer bias or its movement over recent decades. It comprises different subregions where genetic and plumage signals of admixture vary markedly in their concordance. Evidence of contemporary hybridisation (later generation and backcrossed individuals) both within and beyond the previously defined zone, when coupled with a lack of F1 hybrids and differential patterns of introgression among potentially diagnostic loci, indicates a lack of post-zygotic barriers to gene flow between species. Despite ongoing gene flow, species boundaries are likely maintained largely by strong pre-mating barriers. These findings are discussed in detail and future avenues for research into this system are proposed, which would be of benefit to the speciation and hybrid zone literature.


Assuntos
Plumas , Genoma/genética , Hibridização Genética , Papagaios/genética , Animais , Austrália , Especiação Genética , Variação Genética , Papagaios/classificação , Fenótipo , Filogenia , Filogeografia , Locos de Características Quantitativas
19.
Heredity (Edinb) ; 123(5): 608-621, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30874632

RESUMO

Understanding how environmental change has shaped species evolution can inform predictions of how future climate change might continue to do so. Research of widespread biological systems spanning multiple climates that have been subject to environmental change can yield generalizable inferences about the neutral and adaptive processes driving lineage divergence during periods of environmental change. We contribute to the growing body of multi-locus phylogeographic studies investigating the effect of Pleistocene climate change on species evolution by focusing on a widespread Australo-Papuan songbird with several mitochondrial lineages that diverged during the Pleistocene, the grey shrike-thrush (Colluricincla harmonica). We employed multi-locus phylogenetic, population genetic and coalescent analyses to (1) assess whether nuclear genetic diversity suggests a history congruent with that based on phenotypically defined subspecies ranges, mitochondrial clade boundaries and putative biogeographical barriers, (2) estimate genetic diversity within and genetic differentiation and gene flow among regional populations and (3) estimate population divergence times. The five currently recognized subspecies of grey shrike-thrush are genetically differentiated in nuclear and mitochondrial genomes, but connected by low levels of gene flow. Divergences among these populations are concordant with recognized historical biogeographical barriers and date to the Pleistocene. Discordance in the order of population divergence events based on mitochondrial and nuclear genomes suggests a history of sex-biased gene flow and/or mitochondrial introgression at secondary contacts. This study demonstrates that climate change can impact sexes with different dispersal biology in different ways. Incongruence between population and mitochondrial trees calls for a genome-wide investigation into dispersal, mitochondrial introgression and mitonuclear evolution.


Assuntos
Fluxo Gênico , Loci Gênicos , Passeriformes/genética , Caracteres Sexuais , Animais , Austrália , Feminino , Masculino , Filogenia , Filogeografia
20.
Int Orthop ; 43(8): 1793-1798, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30276448

RESUMO

INTRODUCTION: This paper is a short series description of our experience with five cases managed surgically for orthopaedic trauma and who suffered meanwhile an acute coronary event. MATERIALS AND METHODS: Five polytrauma, multiply fractured patients were treated in our institution for various lesions, including an open femur and knee articular fractures, major fractures around the pelvis and hips. They had suffered around the same time an acute coronary event complicating the orthopaedic management. One patient was treated for the orthopaedic condition as a delayed emergency, with a five day retard due to pre-operative pulmonary oedema. Four patients had cardiac evaluation, angiogram or echocardiogram. The patients were managed by a multi-disciplinary team. RESULTS: One patient died post-operatively due to multiple complications, and four patients survived with a good functional outcome. CONCLUSIONS: Patients with acute orthopaedic polytrauma presenting concomitant acute coronary events should be treated by multi-disciplinary teams, allowing early surgical management in a safe cardio-vascular and stable haemodynamic status.


Assuntos
Fraturas Ósseas/cirurgia , Isquemia Miocárdica/complicações , Procedimentos Ortopédicos , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/terapia , Adulto , Idoso , Emergências , Feminino , Fraturas Ósseas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/cirurgia , Isquemia Miocárdica/terapia , Equipe de Assistência ao Paciente , Ferimentos e Lesões/complicações , Ferimentos e Lesões/cirurgia
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