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1.
Mol Phylogenet Evol ; 197: 108085, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38688441

RESUMEN

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.

2.
Mol Ecol ; 32(17): 4844-4862, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37515525

RESUMEN

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.


Asunto(s)
Flujo Génico , Genoma Mitocondrial , Animales , Filogenia , Genoma Mitocondrial/genética , Núcleo Celular/genética , Aves/genética
3.
Syst Biol ; 72(1): 228-241, 2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35916751

RESUMEN

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.].


Asunto(s)
Loros , Humanos , Animales , Filogenia , Loros/genética
4.
Mol Ecol ; 31(19): 5060-5073, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35949055

RESUMEN

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.


Asunto(s)
Passeriformes , Simpatría , Animales , Australia , Flujo Génico , Especiación Genética , Genómica , Passeriformes/genética , beta Catenina/genética
5.
Mol Phylogenet Evol ; 166: 107333, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34688879

RESUMEN

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.


Asunto(s)
Columbidae , ADN Mitocondrial , Animales , Columbidae/genética , ADN Mitocondrial/química , ADN Mitocondrial/genética , Variación Genética , Filogenia , Filogeografía
6.
Mol Phylogenet Evol ; 168: 107379, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34965464

RESUMEN

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.


Asunto(s)
Passeriformes , Animales , Australia , Melanesia , Passeriformes/genética , Filipinas , Filogenia , Filogeografía
7.
Nat Commun ; 12(1): 1023, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33589628

RESUMEN

Australia's 2019-2020 'Black Summer' bushfires burnt more than 8 million hectares of vegetation across the south-east of the continent, an event unprecedented in the last 200 years. Here we report the impacts of these fires on vascular plant species and communities. Using a map of the fires generated from remotely sensed hotspot data we show that, across 11 Australian bioregions, 17 major native vegetation groups were severely burnt, and up to 67-83% of globally significant rainforests and eucalypt forests and woodlands. Based on geocoded species occurrence data we estimate that >50% of known populations or ranges of 816 native vascular plant species were burnt during the fires, including more than 100 species with geographic ranges more than 500 km across. Habitat and fire response data show that most affected species are resilient to fire. However, the massive biogeographic, demographic and taxonomic breadth of impacts of the 2019-2020 fires may leave some ecosystems, particularly relictual Gondwanan rainforests, susceptible to regeneration failure and landscape-scale decline.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Bosque Lluvioso , Incendios Forestales/estadística & datos numéricos , Australia , Bosques , Humanos , Estaciones del Año
8.
Mol Ecol ; 30(9): 2087-2103, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33615597

RESUMEN

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.


Asunto(s)
Flujo Génico , Passeriformes , Animales , Australia , ADN Mitocondrial/genética , Hibridación Genética , Indonesia , Islas , Nueva Guinea , Passeriformes/genética , Filogenia
9.
Sci Rep ; 11(1): 1605, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33452280

RESUMEN

Natural history collections are often plagued by missing or inaccurate metadata for collection items, particularly for specimens that are difficult to verify or rare. Avian eggshell in particular can be challenging to identify due to extensive morphological ambiguity among taxa. Species identifications can be improved using DNA extracted from museum eggshell; however, the suitability of current methods for use on small museum eggshell specimens has not been rigorously tested, hindering uptake. In this study, we compare three sampling methodologies to genetically identify 45 data-poor eggshell specimens, including a putatively extinct bird's egg. Using an optimised drilling technique to retrieve eggshell powder, we demonstrate that sufficient DNA for molecular identification can be obtained from even the tiniest eggshells without significant alteration to the specimen's appearance or integrity. This method proved superior to swabbing the external surface or sampling the interior; however, we also show that these methods can be viable alternatives. We then applied our drilling method to confirm that a purported clutch of Paradise Parrot eggs collected 40 years after the species' accepted extinction date were falsely identified, laying to rest a 53-year-old ornithological controversy. Thus, even the smallest museum eggshells can offer new insights into old questions.


Asunto(s)
Aves/genética , Código de Barras del ADN Taxonómico , Cáscara de Huevo/metabolismo , Loros/genética , Animales , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Museos , Manejo de Especímenes
10.
Braz. oral res. (Online) ; 35: e017, 2021. tab
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1132740

RESUMEN

Abstract Data on dental practices related to caries risk assessment (CRA) are scarce among Brazilian dentists. This study aimed to determine the prevalence of CRA use by dentists and factors associated with its use, as well as to quantify dentists' ratings of the importance of specific factors when treatment planning. Dentists registered at the Regional Council of Dentistry of São Paulo State - Araraquara region were sent two paper questionnaires that comprised: a) characteristics of dentists themselves, their practices, and their patients; and b) the translated version of the "Assessment of Caries Diagnosis and Caries Treatment" Questionnaire from the U.S. National Dental Practice-Based Research Network. Participants were 206 dentists who currently practiced in Araraquara and treated dental caries. Descriptive statistics and multiple logistic regression analyses were used for data analysis. Thirty-six percent of the dentists reported they perform CRA and, among them, 36% indicated they record the assessment on a special form that is kept in the patient chart. More years since dental school graduation (OR = 1.1, p = 0.002) and holding an advanced academic degree (OR=2.6, p=0.005) were associated with a higher likelihood of performing CRA, whereas exclusively using a private practice model (OR = 0.5, p = 0.016) was associated with a lower likelihood of performing CRA. The current oral hygiene and commitment to return for follow-up were the most important risk factors for treatment planning. In conclusion, CRA was not a routine procedure in daily practice among the majority of participating dentists. Specific demographic, practice and academic education characteristics were associated with performing CRA.


Asunto(s)
Humanos , Odontólogos , Brasil/epidemiología , Encuestas y Cuestionarios , Medición de Riesgo , Pautas de la Práctica en Odontología , Caries Dental/epidemiología
11.
Pain Med ; 21(Suppl 2): S62-S72, 2020 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-33313728

RESUMEN

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.


Asunto(s)
Dolor de la Región Lumbar , Veteranos , Humanos , Dolor de la Región Lumbar/terapia , Manejo del Dolor , Ensayos Clínicos Controlados Aleatorios como Asunto , Encuestas y Cuestionarios , Factores de Tiempo
12.
Braz Oral Res ; 35: e017, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33237243

RESUMEN

Data on dental practices related to caries risk assessment (CRA) are scarce among Brazilian dentists. This study aimed to determine the prevalence of CRA use by dentists and factors associated with its use, as well as to quantify dentists' ratings of the importance of specific factors when treatment planning. Dentists registered at the Regional Council of Dentistry of São Paulo State - Araraquara region were sent two paper questionnaires that comprised: a) characteristics of dentists themselves, their practices, and their patients; and b) the translated version of the "Assessment of Caries Diagnosis and Caries Treatment" Questionnaire from the U.S. National Dental Practice-Based Research Network. Participants were 206 dentists who currently practiced in Araraquara and treated dental caries. Descriptive statistics and multiple logistic regression analyses were used for data analysis. Thirty-six percent of the dentists reported they perform CRA and, among them, 36% indicated they record the assessment on a special form that is kept in the patient chart. More years since dental school graduation (OR = 1.1, p = 0.002) and holding an advanced academic degree (OR=2.6, p=0.005) were associated with a higher likelihood of performing CRA, whereas exclusively using a private practice model (OR = 0.5, p = 0.016) was associated with a lower likelihood of performing CRA. The current oral hygiene and commitment to return for follow-up were the most important risk factors for treatment planning. In conclusion, CRA was not a routine procedure in daily practice among the majority of participating dentists. Specific demographic, practice and academic education characteristics were associated with performing CRA.


Asunto(s)
Odontólogos , Brasil/epidemiología , Caries Dental/epidemiología , Humanos , Pautas de la Práctica en Odontología , Medición de Riesgo , Encuestas y Cuestionarios
13.
Heredity (Edinb) ; 125(3): 167, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32694588

RESUMEN

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

14.
Ecol Evol ; 10(13): 6785-6793, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32724551

RESUMEN

We surveyed mitochondrial, autosomal, and Z chromosome diversity within and between the Copperback Quail-thrush Cinclosoma clarum and Chestnut Quail-thrush C. castanotum, which together span the arid and semi-arid zones of southern Australia, and primarily from specimens held in museum collections. We affirm the recent taxonomic separation of the two species and then focus on diversity within the more widespread of the two species, C. clarum. To guide further study of the system and what it offers to understanding the genomics of the differentiation and speciation processes, we develop and present a hypothesis to explain mitonuclear discordance that emerged in ourdata. Following a period of historical allopatry, secondary contact has resulted in an eastern mitochondrial genome replacing the western mitochondrial genome in western populations. This is predicted under a population-level invasion in the opposite direction, that of the western population invading the range of the eastern one. Mitochondrial captures can be driven by neutral, demographic processes, or adaptive mechanisms, and we favor the hypothesized capture being driven by neutral means. We cannot fully reject the adaptive process but suggest how these alternatives may be further tested. We acknowledge an alternative hypothesis, which finds some support in phenotypic data published elsewhere, namely that outcomes of secondary contact have been more complex than our current genomic data suggest. Discriminating and reconciling these two alternative hypotheses, which may not be mutually exclusive, could be tested with closer sampling at levels of population, individual, and nucleotide than has so far been possible. This would be further aided by knowledge of the genetic basis to phenotypic variation described elsewhere.

15.
Heredity (Edinb) ; 125(3): 85-100, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32398870

RESUMEN

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.


Asunto(s)
Cacatúas , Genética de Población , Filogeografía , Animales , Australia , Cacatúas/genética , Conservación de los Recursos Naturales , ADN Mitocondrial , Especies en Peligro de Extinción , Variación Genética , Filogenia , Polimorfismo de Nucleótido Simple
16.
Biol Lett ; 16(5): 20200040, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32396783

RESUMEN

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.


Asunto(s)
Aves , Animales , Asia , Australia , Islas , Nueva Guinea , Filogenia
17.
Syst Biol ; 69(5): 820-829, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32415976

RESUMEN

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.].


Asunto(s)
Evolución Biológica , Aves/clasificación , Aves/fisiología , Comportamiento de Nidificación , Filogenia , Animales
18.
Mol Ecol Resour ; 20(2): 560-578, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31821695

RESUMEN

The superb fairy-wren, Malurus cyaneus, is one of the most iconic Australian passerine species. This species belongs to an endemic Australasian clade, Meliphagides, which diversified early in the evolution of the oscine passerines. Today, the oscine passerines comprise almost half of all avian species diversity. Despite the rapid increase of available bird genome assemblies, this part of the avian tree has not yet been represented by a high-quality reference. To rectify that, we present the first high-quality genome assembly of a Meliphagides representative: the superb fairy-wren. We combined Illumina shotgun and mate-pair sequences, PacBio long-reads, and a genetic linkage map from an intensively sampled pedigree of a wild population to generate this genome assembly. Of the final assembled 1.07-Gb genome, 975 Mb (90.4%) was anchored onto 25 pseudochromosomes resulting in a final superscaffold N50 of 68.11 Mb. This high-quality bird genome assembly is one of only a handful which is also accompanied by a genetic map and recombination landscape. In comparison to other pedigree-based bird genetic maps, we find that the fairy-wren genetic map more closely resembles those of Taeniopygia guttata and Parus major maps, unlike the Ficedula albicollis map which more closely resembles that of Gallus gallus. Lastly, we also provide a predictive gene and repeat annotation of the genome assembly. This new high-quality, annotated genome assembly will be an invaluable resource not only regarding the superb fairy-wren species and relatives but also broadly across the avian tree by providing a novel reference point for comparative genomic analyses.


Asunto(s)
Genoma , Pájaros Cantores/clasificación , Pájaros Cantores/genética , Animales , Australia , Aves/clasificación , Aves/genética , Ligamiento Genético , Filogenia
19.
Rare Tumors ; 11: 2036361319884159, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31741727

RESUMEN

Uterine carcinosarcoma is a rare and aggressive tumor with poor outcomes. Cancer antigen 125 is routinely used to track the disease course of ovarian cancer and has been suggested as a biomarker in other aggressive forms of uterine cancer. We sought to characterize cancer antigen 125 as a potential biomarker of disease status in uterine carcinosarcoma. Clinical and pathological data were abstracted for patients who had surgical staging for a pathologically confirmed uterine carcinosarcoma at our institution from January 2000 to March 2014. Non-parametric tests were used to compare changes in cancer antigen 125. Elevated cancer antigen 125 (>35 U/mL) as a predictor of survival was assessed via Kaplan-Meier curves. Among the 153 patients identified, 66 patients had at least one paired measure of cancer antigen 125 drawn preoperatively, post-treatment, or at the time of disease recurrence, and 19 patients had cancer antigen-125 levels at all three time points. Analysis of the 51 patients with both preoperative and post-treatment values found a significant drop in cancer antigen 125 (p < 0.001). Among the 30 patients who had end-of-treatment and recurrence levels, a significant increase was noted (p = 0.001). There was no significant difference in cancer antigen-125 levels preoperatively compared to at recurrence among the 23 patients with levels at both time-points (p = 0.99). Elevated preoperative cancer antigen 125 was not associated with overall survival (p = 0.12); elevated post-treatment cancer antigen 125 was associated with a worse overall survival (p < 0.001). Based on this dataset, there seems to be utility in trending a cancer antigen-125 level in patients with uterine carcinosarcoma. A cancer antigen-125 level could predict recurrence and provide prognostic information regarding survival.

20.
Proc Biol Sci ; 286(1916): 20192258, 2019 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-31771472

RESUMEN

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.


Asunto(s)
Tamaño Corporal/fisiología , Pájaros Cantores/fisiología , Adaptación Fisiológica , Animales , Australia , Evolución Biológica , Cambio Climático , Fenotipo , Estaciones del Año , Temperatura
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