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1.
Mol Phylogenet Evol ; 175: 107580, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35810968

RESUMO

Several cryptic avian species have been validated by recent integrative taxonomic efforts in the Sino-Himalayan mountains, indicating that avian diversity in this global biodiversity hotspot may be underestimated. In the present study, we investigated species limits in the genus Tarsiger, the bush robins, a group of montane forest specialists with high species richness in the Sino-Himalayan region. Based on comprehensive sampling of all 11 subspecies of the six currently recognized species, we applied an integrative taxonomic approach by combining multilocus, acoustic, plumage and morphometric analyses. Our results reveal that the isolated north-central Chinese populations of Tarsiger cyanurus, described as the subspecies albocoeruleus but usually considered invalid, is distinctive in genetics and vocalisation, but only marginally differentiated in morphology. We also found the Taiwan endemic T. indicus formosanus to be distinctive in genetics, song and morphology from T. i. indicus and T. i. yunnanensis of the Sino-Himalayan mountains. Moreover, Bayesian species delimitation using BPP suggests that both albocoeruleus and formosanus merit full species status. We propose their treatment as 'Qilian Bluetail' T. albocoeruleus and 'Taiwan Bush Robin' T. formosanus, respectively.


Assuntos
Aves Canoras , Animais , Teorema de Bayes , Biodiversidade , Florestas , Filogenia
2.
Mol Phylogenet Evol ; 125: 116-126, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29522814

RESUMO

Species not only responded idiosyncratically to past climate changes, there were also regionally contrasting effects on spatio-temporal diversification patterns. Studies of closely related species appear to be a particularly promising comparative approach to disentangle such regionally differential impacts. In this study, we undertook a comprehensive geographic sampling to investigate the evolutionary history of the Holarctic Sand Martin Riparia riparia and the chiefly Central and East Asian Pale Martin R. diluta. Previous phylogenetic studies using only a limited geographic sampling, particularly for the latter, revealed the two to be genetically distinct, with the former showing only a shallow genetic structure in mitochondrial DNA. Based on one mitochondrial, one autosomal and one Z-linked nuclear marker, we confirmed the shallow genetic structure in R. riparia even when including the morphologically relatively distinct subspecies R. r. shelleyi from the Nile Valley in Egypt and probably the Middle East. On the other hand the different subspecies of R. diluta, i.e. R. d. diluta from Central Asia, R. d. indica from the northwestern Indian Subcontinent, R. d. tibetana from the Tibetan Plateau and R. d. fohkienensis from southeastern China, were found to be genetically distinct. Their diversification started before the Early to Middle Pleistocene Transition, which was followed by a pronounced succession of glacial and interglacial periods. These rather old divergence events contrast with the lack of any strong phylogeographic structure in R. riparia. Strongly structured populations and regional diversification have been reported in different forest passerine families of South-East Asia. Here we demonstrate, however, that species characteristic of open-country habitats such as R. diluta might display a similar pattern. Morphometric analyses of 120 individuals revealed no clear differences between the different subspecies of R. diluta. Given their similarity also in plumage features, we refrain from proposing any splits despite their marked genetic differentiation, pending further studies and particularly the discovery of potential secondary contact zones.


Assuntos
Variação Genética , Andorinhas/genética , Animais , Sequência de Bases , Teorema de Bayes , Cruzamento , Calibragem , Núcleo Celular/genética , DNA Mitocondrial/genética , Marcadores Genéticos , Geografia , Haplótipos/genética , Filogenia , Filogeografia , Análise de Componente Principal , Especificidade da Espécie , Andorinhas/anatomia & histologia
3.
BMC Cell Biol ; 15: 6, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24528853

RESUMO

BACKGROUND: Research antibodies are used by thousands of scientists working in diverse disciplines, but it is common to hear concerns about antibody quality. This means that researchers need to carefully choose the antibodies they use to avoid wasting time and money. A well accepted way of selecting a research antibody is to identify one which has been used previously, where the associated data has been peer-reviewed and the results published. DESCRIPTION: CiteAb is a searchable database which ranks antibodies by the number of times they have been cited. This allows researchers to easily find antibodies that have been used in peer-reviewed publications and the accompanying citations are listed, so users can check the data contained within the publications. This makes CiteAb a useful resource for identifying antibodies for experiments and also for finding information to demonstrate antibody validation. The database currently contains 1,400,000 antibodies which are from 90 suppliers, including 87 commercial companies and 3 academic resources. Associated with these antibodies are 140,000 publications which provide 306,000 antibody citations. In addition to searching, users can also browse through the antibodies and add their own publications to the CiteAb database. CONCLUSIONS: CiteAb provides a new way for researchers to find research antibodies that have been used successfully in peer-reviewed publications. It aims to assist these researchers and will hopefully help promote progress in many areas of life science research.


Assuntos
Anticorpos/análise , Bases de Dados de Proteínas , Ferramenta de Busca , Interface Usuário-Computador , Animais , Humanos , Internet
4.
Ecol Indic ; 45: 266-273, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25045322

RESUMO

Satellite-based tracking of migratory waterfowl is an important tool for understanding the potential role of wild birds in the long-distance transmission of highly pathogenic avian influenza. However, employing this technique on a continental scale is prohibitively expensive. This study explores the utility of stable isotope ratios in feathers in examining both the distances traveled by migratory birds and variation in migration behavior. We compared the satellite-derived movement data of 22 ducks from 8 species captured at wintering areas in Bangladesh, Turkey, and Hong Kong with deuterium ratios (δD) of these and other individuals captured at the same locations. We derived likely molting locations from the satellite tracking data and generated expected isotope ratios based on an interpolated map of δD in rainwater. Although δD was correlated with the distance between wintering and molting locations, surprisingly, measured δD values were not correlated with either expected values or latitudes of molting sites. However, population-level parameters derived from the satellite-tracking data, such as mean distance between wintering and molting locations and variation in migration distance, were reflected by means and variation of the stable isotope values. Our findings call into question the relevance of the rainfall isotope map for Asia for linking feather isotopes to molting locations, and underscore the need for extensive ground truthing in the form of feather-based isoscapes. Nevertheless, stable isotopes from feathers could inform disease models by characterizing the degree to which regional breeding populations interact at common wintering locations. Feather isotopes also could aid in surveying wintering locations to determine where high-resolution tracking techniques (e.g. satellite tracking) could most effectively be employed. Moreover, intrinsic markers such as stable isotopes offer the only means of inferring movement information from birds that have died as a result of infection. In the absence of feather based-isoscapes, we recommend a combination of isotope analysis and satellite-tracking as the best means of generating aggregate movement data for informing disease models.

5.
Mol Phylogenet Evol ; 67(1): 72-85, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23321212

RESUMO

We use the mitochondrial cytochrome b from 213 individuals and the three nuclear introns BRM 15, myoglobin 2 and ODC 6-7 from a smaller subsample to evaluate the taxonomy of the Lesser Whitethroat Sylvia curruca (Aves, Passeriformes, Sylviidae) complex, which has long been controversial. We sequenced type material of the taxa althaea, blythi, margelanica and minula, and used topotypical material of caucasica, chuancheica, curruca and telengitica. The nuclear introns fail to resolve the complex, but cytochrome b recovers six major clades, revealing genetically identifiable populations corresponding to previously named taxa, and we propose that the names althaea, blythi, curruca, halimodendri, margelanica and minula, respectively, should be used for these. The margelanica clade is suggested to have a more extensive distribution than previously known, including both the taxon telengitica and a population in eastern Mongolia. The taxon minula is found to have a more restricted range than generally believed, only breeding in China. According to the mitochondrial gene tree, there is a basal dichotomy, with the taxa althaea, blythi, halimodendri and margelanica being part of one clade, well separated from a clade containing curruca and minula. Dating analysis suggests that a basal divergence separating curruca and minula from the other four taxa occurred between 4.2 and 7.2 mya; these two then diverged between 2.3 and 4.4 mya. The splits between the althaea, blythi, halimodendri and margelanica lineages is inferred to have occurred later, approximately between 1.0 and 2.5 mya (all 95% HPD). The nucleotide data suggest significant departure from demographic equilibrium in blythi (clade 1a), halimodendri (clade 2a) and minula, whereas tendencies are weaker for other clades. We propose that the names althaea, blythi, curruca, halimodendri, margelanica and minula should be used for the major clades. However, whether these are treated as subspecies or species is largely a matter of species definition and is not resolved by our data.


Assuntos
Evolução Molecular , Passeriformes/classificação , Filogenia , Animais , Teorema de Bayes , China , Citocromos b/genética , DNA Mitocondrial/genética , Genética Populacional , Íntrons , Modelos Genéticos , Passeriformes/genética , Alinhamento de Sequência , Análise de Sequência de DNA
6.
Ecol Evol ; 11(1): 11-21, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33437411

RESUMO

Molt strategies have received relatively little attention in current ornithology, and knowledge concerning the evolution, variability and extent of molt is sparse in many bird species. This is especially true for East Asian Locustella species where assumptions on molt patterns are based on incomplete information. We provide evidence indicating a complex postbreeding molt strategy and variable molt extent among the Pallas's Grasshopper Warbler Locustella certhiola, based on data from six ringing sites situated along its flyway from the breeding grounds to the wintering areas. Detailed study revealed for the first time that in most individuals wing feather molt proceeds from the center both toward the body and the wing-tip, a molt pattern known as divergent molt (which is rare among Palearctic passerines). In the Russian Far East, where both breeding birds and passage migrants occur, a third of the adult birds were molting in late summer. In Central Siberia, at the northwestern limit of its distribution, adult individuals commenced their primary molt partly divergently and partly with unknown sequence. During migration in Mongolia, only descendantly (i.e., from the body toward the wing-tip) molting birds were observed, while further south in Korea, Hong Kong, and Thailand the proportion of potential eccentric and divergent feather renewal was not identifiable since the renewed feathers were already fully grown as expected. We found an increase in the mean number of molted primaries during the progress of the autumn migration. Moderate body mass levels and low-fat and muscle scores were observed in molting adult birds, without any remarkable increase in the later season. According to optimality models, we suggest that an extremely short season of high food abundance in tall grass habitats and a largely overland route allow autumn migration with low fuel loads combined with molt migration in at least a part of the population. This study highlights the importance of further studying molt strategy as well as stopover behavior decisions and the trade-offs among migratory birds that are now facing a panoply of anthropogenic threats along their flyways.

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