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1.
Nature ; 579(7797): 92-96, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32076267

RESUMO

Colonization, speciation and extinction are dynamic processes that influence global patterns of species richness1-6. Island biogeography theory predicts that the contribution of these processes to the accumulation of species diversity depends on the area and isolation of the island7,8. Notably, there has been no robust global test of this prediction for islands where speciation cannot be ignored9, because neither the appropriate data nor the analytical tools have been available. Here we address both deficiencies to reveal, for island birds, the empirical shape of the general relationships that determine how colonization, extinction and speciation rates co-vary with the area and isolation of islands. We compiled a global molecular phylogenetic dataset of birds on islands, based on the terrestrial avifaunas of 41 oceanic archipelagos worldwide (including 596 avian taxa), and applied a new analysis method to estimate the sensitivity of island-specific rates of colonization, speciation and extinction to island features (area and isolation). Our model predicts-with high explanatory power-several global relationships. We found a decline in colonization with isolation, a decline in extinction with area and an increase in speciation with area and isolation. Combining the theoretical foundations of island biogeography7,8 with the temporal information contained in molecular phylogenies10 proves a powerful approach to reveal the fundamental relationships that govern variation in biodiversity across the planet.


Assuntos
Biodiversidade , Aves/classificação , Ilhas , Modelos Biológicos , Animais , Bases de Dados de Ácidos Nucleicos , Extinção Biológica , Especiação Genética , Filogenia , Filogeografia
2.
Nat Commun ; 10(1): 4757, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628336

RESUMO

Recent progress in remote sensing provides much-needed, large-scale spatio-temporal information on habitat structures important for biodiversity conservation. Here we examine the potential of a newly launched satellite-borne radar system (Sentinel-1) to map the biodiversity of twelve taxa across five temperate forest regions in central Europe. We show that the sensitivity of radar to habitat structure is similar to that of airborne laser scanning (ALS), the current gold standard in the measurement of forest structure. Our models of different facets of biodiversity reveal that radar performs as well as ALS; median R² over twelve taxa by ALS and radar are 0.51 and 0.57 respectively for the first non-metric multidimensional scaling axes representing assemblage composition. We further demonstrate the promising predictive ability of radar-derived data with external validation based on the species composition of birds and saproxylic beetles. Establishing new area-wide biodiversity monitoring by remote sensing will require the coupling of radar data to stratified and standardized collected local species data.


Assuntos
Biodiversidade , Florestas , Radar , Tecnologia de Sensoriamento Remoto/métodos , Árvores/fisiologia , Animais , Aves/classificação , Aves/fisiologia , Besouros/classificação , Besouros/fisiologia , Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Reprodutibilidade dos Testes , Análise Espaço-Temporal , Árvores/classificação
3.
BMC Evol Biol ; 19(1): 189, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619159

RESUMO

BACKGROUND: Many living birds exhibit some nocturnal activity, but the genetic basis and evolutionary origins of their nocturnality remain unknown. RESULTS: Here, we used a molecular phyloecological approach to analyze the adaptive evolution of 33 phototransduction genes in diverse bird lineages. Our results suggest that functional enhancement of two night-vision genes, namely, GRK1 and SLC24A1, underlies the nocturnal adaption of living birds. Further analyses showed that the diel activity patterns of birds have remained relatively unchanged since their common ancestor, suggesting that the widespread nocturnal activity of many living birds may largely stem from their common ancestor rather than independent evolution. Despite this evolutionary conservation of diel activity patterns in birds, photoresponse recovery genes were found to be frequently subjected to positive selection in diverse bird lineages, suggesting that birds generally have evolved an increased capacity for motion detection. Moreover, we detected positive selection on both dim-light vision genes and bright-light vision genes in the class Aves, suggesting divergent evolution of the vision of birds from that of reptiles and that different bird lineages have evolved certain visual adaptions to their specific light conditions. CONCLUSIONS: This study suggests that the widespread nocturnality of extant birds has a deep evolutionary origin tracing back to their common ancestor.


Assuntos
Comportamento Animal/fisiologia , Aves/classificação , Filogenia , Animais , Aves/genética , Transdução de Sinal Luminoso/genética , Seleção Genética , Software
4.
Artigo em Inglês | MEDLINE | ID: mdl-31476363

RESUMO

Understanding variation in physiological traits across taxa is a central question in evolutionary biology that has wide-ranging implications in biomedicine, disease ecology, and environmental protection. Sialic acid (Sia), and in particular, 5-N-acetylneuraminic acid (Neu5Ac), is chemically bound to galactose and the underlying glycan via α2-3 or α2-6 glycosidic linkage (i.e., Siaα2-3Galactose or Siaα2-6Galactose), conferring two different cell surface structures that affects cell to cell communication and interactions with foreign agents including microparasites and toxins. As an initial step towards understanding variation of Sia across the class Aves, we collected red blood cells (RBCs or erythrocytes) and measured Sia quantity in 76 species and 340 individuals using HPLC-MS/MS and glycosidic linkage type in 24 species and 105 individuals using hemagglutination assay. Although Sia quantity did not, α2-6 glycosidic linkage did exhibit a discernable phylogenetic pattern as evaluated by a phylogenetic signal (λ) value of 0.7. Sia quantity appeared to be higher in after hatch year birds than hatch year birds (P < 0.05); moreover, ~80% of the measured Sia across all individuals or species was expressed by ~20% of the individuals or species. Lastly, as expected, we detected a minimal presence of 5-N-glycolylneuraminic acid in the avian RBCs tested. These data provide novel insights and a large baseline dataset for further study on the variability of Sia in the class Aves which might be useful for understanding Sia dependent processes in birds.


Assuntos
Aves/metabolismo , Eritrócitos/metabolismo , Ácidos Siálicos/metabolismo , Animais , Aves/classificação , Eritrócitos/química , Ácidos Siálicos/química , Especificidade da Espécie
5.
J Ethnobiol Ethnomed ; 15(1): 46, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477132

RESUMO

BACKGROUND: Hornbills are known to play an important role in rainforests as agents of seed dispersal. Decades of scientific research has led to a vital body of knowledge on hornbill taxonomy, ecology, distribution, and conservation status. However, the traditional ecological knowledge (TEK) that local people possess on hornbills has largely been underexplored. In 2018, we collaborated with the Iban people of Temburong, Brunei Darussalam, to study their TEK on hornbills. METHOD: We collaborated with the members of the Iban community from four longhouses and four villages in Temburong, Brunei Darussalam. Our study adopts a qualitative approach; we used detailed semi-directive interviews and brief semi-structured interviews to gather data. The semi-directive interviews documented the TEK related to Hornbills in detail while the brief semi-structured interviews assessed the current status of TEK in the age group of 18-40 years. RESULTS: The results show that the Iban ethnotaxonomy recognises seven folk species of hornbills, with Asian Black Hornbill (Anthracoceros malayanus) and Oriental Pied Hornbill (Anthracoceros albirostris) considered as a single folk species. The Iban TEK on diet and reproductive behaviour of hornbills complement existing scientific records, with the Iban TEK providing additional locale-specific information on the dietary preferences, abundance and conservation threats. However, the average Iban member has lost much of this TEK, and it is the subsistence hunters and agriculturists who have conserved it. CONCLUSION: There is an urgent need for encouraging transmission of knowledge from the hunters and agriculturists to others through ecotourism and conservation ventures. Our study adds further support to the understanding that the TEK of local communities is an important source of locale-specific knowledge on species of high conservation value such as hornbills.


Assuntos
Aves/classificação , Ecologia , Conhecimento , Adolescente , Adulto , Animais , Brunei , Conservação dos Recursos Naturais , Grupos Étnicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dispersão de Sementes , Adulto Jovem
6.
An Acad Bras Cienc ; 91(suppl 3): e20190218, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31411243

RESUMO

Amazonia has been a focus of interest since the early days of biogeography as an intrinsically complex and extremely diverse region. This region comprises an intricate mosaic that includes diverse types of forest formations, flooded environments and open vegetation. Increased knowledge about the distribution of species in Amazonia has led to the recognition of complex biogeographic patterns. The confrontation of these biogeographic patterns with information on the geological and climatic history of the region has generated several hypotheses dedicated to explain the origin of the biological diversity. Genomic information, coupled with knowledge of Earth's history, especially the evolution of the Amazonian landscape, presents fascinating possibilities for understanding the mechanisms that govern the origin and maintenance of diversity patterns in one of the most diverse regions of the world. For this we will increasingly need more intense and coordinated interactions between researchers studying biotic diversification and the evolution of landscapes. From the interaction between these two fields of knowledge that are in full development, an increasingly detailed understanding of the historical mechanisms related to the origin of the species will surely arise.


Assuntos
Biodiversidade , Evolução Biológica , Aves/classificação , Filogeografia , Animais , Brasil , Ecossistema
7.
Nature ; 572(7771): 651-654, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31413362

RESUMO

The origins of endothermy in birds and mammals are important events in vertebrate evolution. Endotherms can maintain their body temperature (Tb) over a wide range of ambient temperatures primarily using the heat that is generated continuously by their high basal metabolic rate (BMR)1. There is also an important positive feedback loop as Tb influences BMR1-3. Owing to this interplay between BMRs and Tb, many ecologists and evolutionary physiologists posit that the evolution of BMR and Tb must have been coupled during the radiation of endotherms3-5, changing with similar trends6-8. However, colder historical environments might have imposed strong selective pressures on BMR to compensate for increased rates of heat loss and to keep Tb constant9-12. Thus, adaptation to cold ambient temperatures through increases in BMR could have decoupled BMR from Tb and caused different evolutionary routes to the modern diversity in these traits. Here we show that BMR and Tb were decoupled in approximately 90% of mammalian phylogenetic branches and 36% of avian phylogenetic branches. Mammalian BMRs evolved with rapid bursts but without a long-term directional trend, whereas Tb evolved mostly at a constant rate and towards colder bodies from a warmer-bodied common ancestor. Avian BMRs evolved predominantly at a constant rate and without a long-term directional trend, whereas Tb evolved with much greater rate heterogeneity and with adaptive evolution towards colder bodies. Furthermore, rapid shifts that lead to both increases and decreases in BMRs were linked to abrupt changes towards colder ambient temperatures-although only in mammals. Our results suggest that natural selection effectively exploited the diversity in mammalian BMRs under diverse, often-adverse historical thermal environments.


Assuntos
Metabolismo Basal/fisiologia , Evolução Biológica , Temperatura Corporal/fisiologia , Animais , Aves/classificação , Aves/metabolismo , Regulação da Temperatura Corporal/fisiologia , Mamíferos/classificação , Mamíferos/metabolismo , Filogenia
8.
Nature ; 571(7763): 103-106, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31217580

RESUMO

Human-mediated translocation of species to areas beyond their natural distribution (which results in 'alien' populations1) is a key signature of the Anthropocene2, and is a primary global driver of biodiversity loss and environmental change3. Stemming the tide of invasions requires understanding why some species fail to establish alien populations, and others succeed. To achieve this, we need to integrate the effects of features of the introduction site, the species introduced and the specific introduction event. Determining which, if any, location-level factors affect the success of establishment has proven difficult, owing to the multiple spatial, temporal and phylogenetic axes along which environmental variation may influence population survival. Here we apply Bayesian hierarchical regression analysis to a global spatially and temporally explicit database of introduction events of alien birds4 to show that environmental conditions at the introduction location, notably climatic suitability and the presence of other groups of alien species, are the primary determinants of successful establishment. Species-level traits and the size of the founding population (propagule pressure) exert secondary, but important, effects on success. Thus, current trajectories of anthropogenic environmental change will most probably facilitate future incursions by alien species, but predicting future invasions will require the integration of multiple location-, species- and event-level characteristics.


Assuntos
Biodiversidade , Aves , Mapeamento Geográfico , Internacionalidade , Espécies Introduzidas/estatística & dados numéricos , Migração Animal , Animais , Aves/classificação , Atividades Humanas , Filogenia , Densidade Demográfica , Dinâmica Populacional , Probabilidade , Especificidade da Espécie
9.
PLoS One ; 14(6): e0218506, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242207

RESUMO

Genetically related highly pathogenic avian influenza viruses (HPAIVs) of H5N6 subtype caused outbreaks simultaneously in East Asia and Europe-geographically distinct regions-during winter 2017-2018. This situation prompted us to consider whether the application of phylogeographic analysis to a particular gene segment of AIVs could provide clues for understanding how AIV had been disseminated across the continent. Here, the N6 NA genes of influenza viruses isolated across the world were subjected to phylogeographic analysis to illustrate the inter- and intracontinental dissemination of AIVs. Those isolated in East Asia during winter and in Mongolia/Siberia during summer were comingled within particular clades of the phylogeographic tree. For AIVs in one clade, their dissemination in eastern Eurasia extended from Yakutia, Russia, in the north to East Asia in the south. AIVs in western Asia, Europe, and Mongolia were also comingled within other clades, indicating that Mongolia/Siberia plays an important role in the dissemination of AIVs across the Eurasian continent. Mongolia/Siberia may therefore have played a role in the simultaneous outbreaks of H5N6 HPAIVs in Europe and East Asia during the winter of 2017-2018. In addition to the long-distance intracontinental disseminations described above, intercontinental disseminations of AIVs between Eurasia and Africa and between Eurasia and North America were also observed. Integrating these results and known migration flyways suggested that the migration of wild birds and the overlap of flyways, such as that observed in Mongolia/Siberia and along the Alaskan Peninsula, contributed to the long-distance intra- and intercontinental dissemination of AIVs. These findings highlight the importance of understanding the movement of migratory birds and the dynamics of AIVs in breeding areas-especially where several migration flyways overlap-in forecasting outbreaks caused by HPAIVs.


Assuntos
Migração Animal , Animais Selvagens/virologia , Aves/virologia , Vírus da Influenza A/isolamento & purificação , Animais , Animais Selvagens/classificação , Ásia/epidemiologia , Aves/classificação , Surtos de Doenças/veterinária , Reservatórios de Doenças/virologia , Europa (Continente)/epidemiologia , Voo Animal , Genes Virais , Interações entre Hospedeiro e Microrganismos/genética , Especificidade de Hospedeiro/genética , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , América do Norte/epidemiologia , Filogenia , Filogeografia
10.
Genome Biol Evol ; 11(6): 1552-1572, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31114863

RESUMO

High-elevation organisms experience shared environmental challenges that include low oxygen availability, cold temperatures, and intense ultraviolet radiation. Consequently, repeated evolution of the same genetic mechanisms may occur across high-elevation taxa. To test this prediction, we investigated the extent to which the same biochemical pathways, genes, or sites were subject to parallel molecular evolution for 12 Andean hummingbird species (family: Trochilidae) representing several independent transitions to high elevation across the phylogeny. Across high-elevation species, we discovered parallel evolution for several pathways and genes with evidence of positive selection. In particular, positively selected genes were frequently part of cellular respiration, metabolism, or cell death pathways. To further examine the role of elevation in our analyses, we compared results for low- and high-elevation species and tested different thresholds for defining elevation categories. In analyses with different elevation thresholds, positively selected genes reflected similar functions and pathways, even though there were almost no specific genes in common. For example, EPAS1 (HIF2α), which has been implicated in high-elevation adaptation in other vertebrates, shows a signature of positive selection when high-elevation is defined broadly (>1,500 m), but not when defined narrowly (>2,500 m). Although a few biochemical pathways and genes change predictably as part of hummingbird adaptation to high-elevation conditions, independent lineages have rarely adapted via the same substitutions.


Assuntos
Aves/classificação , Aves/fisiologia , Evolução Molecular , Adaptação Fisiológica , Altitude , Animais , Aves/genética , Perfilação da Expressão Gênica , Redes e Vias Metabólicas
11.
Environ Pollut ; 251: 717-722, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31108305

RESUMO

Human pressure exerts a significant influence on animals and the environment. One of its consequences, plastic pollution is considered one of the major threats to fauna as well as a significant conservation issue. In this research, we examined the global pattern of one example of avian behavior in response to pollution-namely, the incorporation of anthropogenic materials into nests-as well as the existing knowledge on this subject. Based on 25 articles, we studied 51 populations, involving 24 bird species, and checked 10,790 nests; as a result, we found that incorporation of debris is correlated with increasing human influence on the environment, measured as the Human Footprint Index. Moreover, the probability of debris incorporation is higher in terrestrial than in marine species. We also identified knowledge bias in favor of marine as opposed to terrestrial species: namely, marine species attract more scientific attention than terrestrial. Furthermore, research approaches to these two ecosystems differ. Undeniably, the factors which influence debris incorporation by birds, the scale of this behavior, and particular forms of use of debris in bird nests are aspects which require long-term standardized research. This is the first global review paper on debris incorporation by birds to demonstrate a close link to human pressure as a driver.


Assuntos
Aves/fisiologia , Poluentes Ambientais/análise , Comportamento de Nidação/fisiologia , Animais , Aves/classificação , Ecossistema , Biomarcadores Ambientais/fisiologia , Humanos , Plásticos/análise , Especificidade da Espécie , Resíduos/análise
12.
PLoS One ; 14(5): e0214653, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31042737

RESUMO

Pacific martens (Martes caurina) are often associated with mature forests with complex structure for denning, resting, and efficient hunting. Nonetheless, a small isolated population of the Humboldt subspecies of Pacific martens (Martes caurina humboldtensis) occupies a narrow strip of young, coastal forest (< 70 years old) but not inland mature forest in the central Oregon Coast Range. We examined factors contributing to this unexpected distribution of martens by 1) analyzing marten diets using DNA metabarcoding to assess 90 scats, 2) using camera traps to assess differences in the relative abundances of prey, competitors, and predators across a coastal to inland gradient of vegetation types, and 3) quantifying differences in extent of fruit-producing shrubs and vegetation structure within vegetation types. Diets of martens were diverse (12, 10, and 3 species of birds, mammals, and amphibians respectively), and most fall and winter scats contained fruit. Voles, mice, and varied thrushes (Ixoreus naevius) were dominant prey items. Voles, mice, and most birds, but not varied thrushes, were more commonly observed in the coastal shrub-dominated forest than in inland forest. The coastal shrub-dominated forest had the highest diversity of vertebrates and potential prey overall. Bobcats (Lynx rufus), a key potential predator, were more commonly detected in inland forest. Of potential competitors, western spotted skunks (Spilogale gracilis) were more commonly detected in inland forest, with gray foxes (Urocyon cinereoargenteus) and raccoons (Procyon lotor) detected almost exclusively in coastal forests. Vegetation in coastal forests appears to provide, at least seasonally, more prey and fruit, and more overhead shrub cover compared with inland forest. Remaining plausible hypotheses for the restricted distribution of marten to coastal forests include increased prey, fruit, and overhead cover, and reduced predation risk from bobcats.


Assuntos
Anfíbios/classificação , Aves/classificação , Código de Barras de DNA Taxonômico/métodos , Mamíferos/classificação , Mustelidae/fisiologia , Anfíbios/genética , Animais , Aves/genética , Demografia , Dieta , Herbivoria , Mamíferos/genética , Comportamento Predatório , Gravação em Vídeo
13.
PLoS One ; 14(5): e0215525, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31059549

RESUMO

Cities comprise of mixed green patches that vary in size and are highly scattered and disconnected. Although small green spaces largely dominate the cityscape, they are often neglected and ignored by the naturalists and conservationists, as they do not fulfill the large green spaces criteria. The citizens on the other hand seem to have a different perception and requirements from small green spaces as they are within their neighbourhood. Bangalore, a developing city within South India, consists of a large number of newly formed residential areas which have pocket green spaces in the form of neighbourhood parks (henceforth NPs). They are maintained by the municipality and are mainly designed for recreation purposes, completely neglecting the fact that these spaces could be essential for biodiversity. Here, there is a disconnect between the requirements of the citizens, conservationists and the end product that the municipality delivers. Here, through a questionnaire survey we assess the biodiversity citizens are fond off, and use them as surrogate taxa for the not so immediately obvious taxa, insects to enumerate the biodiversity within NPs. We analyze and identify landscape characteristics around NPs which could enhance the biodiversity within NPs. Our results reveal that people are fond of Birds and Butterflies and we use them as surrogates for the inconspicuous taxa to assess biodiversity within NPs. 55 tree species, 45 species of birds, 41 species of butterflies and 68 morpho species of insects were recorded. We demonstrate that small green spaces are critical systems and help support biodiversity across three scale within the city. Interestingly, results suggests that density of NPs is more important rather than the size of NPs. Also, the presence of high density of NPs within a neighbourhood could support similar biodiversity that large green spaces support. Finally, this study provides insights on the landscape matrix that could help enhance biodiversity support service within NPs and the surrounding neighbourhood.


Assuntos
Aves/classificação , Borboletas/classificação , Conservação dos Recursos Naturais/métodos , Insetos/classificação , Árvores/classificação , Animais , Biodiversidade , Cidades , Humanos , Índia , Parques Recreativos , Características de Residência , Inquéritos e Questionários
14.
Rev Bras Parasitol Vet ; 28(2): 187-193, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31141018

RESUMO

Portugal has some rehabilitation centers for wild animals, which are responsible for the rehabilitation and reintroduction of birds, among other animals, into the wild. Coccidian parasites of these wild birds in rehabilitation centers are especially important because these centers can introduce coccidian species into new environments through the reintroduction of their respective hosts. In this context, the current study aimed to identify intestinal coccidia from wild birds at two rehabilitation centers for wild animals located in two municipalities of Portugal. Eighty-nine wild birds of 9 orders and 11 families were sampled, of which 22 (25%) were positive for Coccidia. Avispora spp. were found in raptors. Sporocysts of Sarcocystinae subfamily were recovered from owls. An Isospora sp. was found in Turdus merula Linnaeus, 1758, and an Eimeria sp. was found in Fulica atra Linnaeus, 1758. Among the coccidian species, Avispora bubonis (Cawthorn, Stockdale, 1981) can be highlighted. The finding of this species indicates that transmission of coccidians from the New World to the Old World may be occurring, potentially through dispersion by Bubo scandiacus (Linnaeus, 1758) through Arctic regions or by means of anthropic activities, and/or through other unknown mechanisms.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Coccídios/isolamento & purificação , Coccidiose/veterinária , Animais , Animais Selvagens , Aves/classificação , Coccídios/classificação , Coccidiose/diagnóstico , Fezes/parasitologia , Portugal , Centros de Reabilitação
15.
Genes Genomics ; 41(9): 1015-1026, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31134591

RESUMO

BACKGROUND: In the North Pacific, northern fulmar (Fulmarus glacialis) forms extensive colonies in few locales, which may lead to limited gene flow and locale-specific population threats. In the Atlantic, there are thousands of colonies of varying sizes and in Europe the species is considered threatened. Prior screens and classical microsatellite development in fulmar failed to provide a suite of markers adequate for population genetics studies. OBJECTIVES: The objective of this study was to isolate a suite of polymorphic microsatellite loci with sufficient variability to quantify levels of gene flow, population affinity, and identify familial relationships in fulmar. We also performed a cross-species screening of these markers in eight other species. METHODS: We used shotgun sequencing to isolate 26 novel microsatellite markers in fulmar to screen for variability using individuals from two distinct regions: the Pacific (Chagulak Island, Alaska) and the Atlantic (Hafnarey Island, Iceland). RESULTS: Polymorphism was present in 24 loci in Chagulak and 23 in Hafnarey, while one locus failed to amplify in either colony. Polymorphic loci exhibited moderate levels of genetic diversity and this suite of loci uncovered genetic structuring between the regions. Among the other species screened, polymorphism was present in one to seven loci. CONCLUSION: The loci yielded sufficient variability for use in population studies and estimation of familial relationships; as few as five loci provide resolution to determine individual identity. These markers will allow further insight into the global population dynamics and phylogeography of fulmars. We also demonstrated some markers are transferable to other species.


Assuntos
Aves/genética , Repetições de Microssatélites , Filogenia , Polimorfismo Genético , Animais , Aves/classificação , Evolução Molecular , Amplificação de Genes , Fluxo Gênico
16.
J Parasitol ; 105(2): 334-344, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31021736

RESUMO

Chewing lice (Insecta: Phthiraptera) are abundant ectoparasites of birds and mammals. They are adapted to life in the plumage or pelage of their hosts and virtually never leave the host during their life cycle. Most species are highly host specific. This study was carried out to determine species richness, abundance, and prevalence of chewing lice of wild forest birds in the southern region of China. Between July 2012 and June 2016, 2,210 birds (belonging to 8 orders, 45 families, and 215 species) were captured by mist nets and examined for chewing lice. In total, 622 birds of 117 species were parasitized by lice belonging to 89 species in 25 genera from 2 suborders (Amblycera and Ischnocera). Of these, 28 louse species represent new host-louse records for China and 10 worldwide. Chewing louse prevalence varied significantly among host species. There was no evidence of a correlation between climate zones and louse prevalence, but host guild affected prevalence significantly, with insectivorous birds having the lowest prevalence. Louse prevalence was positively correlated with host body mass and bill length, but mean intensity was only correlated with host body mass. These findings contribute further knowledge of avian chewing lice.


Assuntos
Doenças das Aves/parasitologia , Aves/anatomia & histologia , Tamanho Corporal/fisiologia , Infestações por Piolhos/veterinária , Ftirápteros/crescimento & desenvolvimento , Migração Animal , Animais , Animais Selvagens , Bico/anatomia & histologia , Doenças das Aves/epidemiologia , Aves/classificação , Aves/parasitologia , China/epidemiologia , Clima , Dieta/veterinária , Interações Hospedeiro-Parasita , Infestações por Piolhos/epidemiologia , Infestações por Piolhos/parasitologia , Ftirápteros/fisiologia , Prevalência
17.
PLoS One ; 14(4): e0215229, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973922

RESUMO

Although the impacts of climate change on biodiversity are increasing worldwide, few studies have attempted to forecast these impacts on Amazon Tropical Forest. In this study, we estimated the impact of climate change on Amazonian avian assemblages considering range shifts, species loss, vulnerability of ecosystem functioning, future effectiveness of current protected areas and potential climatically stable areas for conservation actions. Species distribution modelling based on two algorithms and three different scenarios of climate change was used to forecast 501 avian species, organized on main ecosystem functions (frugivores, insectivores and nectarivores) for years 2050 and 2070. Considering the entire study area, we estimated that between 4 and 19% of the species will find no suitable habitat. Inside the currently established protected areas, species loss could be over 70%. Our results suggest that frugivores are the most sensitive guild, which could bring consequences on seed dispersal functions and on natural regeneration. Moreover, we identified the western and northern parts of the study area as climatically stable. Climate change will potentially affect avian assemblages in southeastern Amazonia with detrimental consequences to their ecosystem functions. Information provided here is essential to conservation practitioners and decision makers to help on planning their actions.


Assuntos
Aves , Mudança Climática , Floresta Úmida , Algoritmos , Animais , Biodiversidade , Aves/classificação , Brasil , Conservação dos Recursos Naturais , Ecossistema , Florestas , Aquecimento Global , Modelos Biológicos
18.
Mol Genet Genomics ; 294(3): 679-692, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30834967

RESUMO

Cathartidae is a small family of large-bodied carrion-feeding birds, of which the turkey vulture (Cathartes aura, Cathartidae) is the most widespread distributed. To investigate the chemoreception system, detoxification system, and immune system in the turkey vulture, we compared its genome to 14 other avian genomes. Comparative genomics demonstrated the expansion in the chemoreception system, especially the olfactory receptors, while the genes in the detoxification system of the turkey vulture did not show apparent expansion. We identified five positively selected genes associated with the immune system in the turkey vulture, which was likely to strengthen the immune defense against pathogenic invasion. Functional enrichment analysis indicated that many positively selected genes were involved in the regulation of immune system processes, implying important reorganization of the immune system in the turkey vulture. The turkey vulture-specific missense mutations were found in one positively selected gene (BCL6), and all the missense mutations were classified as deleterious by PolyPhen-2, possibly contributing to immune adaptation to the carrion feeding. Furthermore, we identified four turkey vulture-specific missense mutations in three ß-defensin genes of the turkey vulture, which was an indispensable part in the innate immunity (a natural barrier against invasive microbes including bacteria, fungi, and viruses). Our genomic analyses in the turkey vulture provided insights into the genetic signatures of the adaptation to the carrion feeding.


Assuntos
Proteínas Aviárias/genética , Aves/genética , Genoma/genética , Genômica/métodos , Sequência de Aminoácidos , Animais , Bactérias/patogenicidade , Aves/classificação , Aves/microbiologia , Comportamento Alimentar , Fungos/patogenicidade , Sistema Imunitário/metabolismo , Sistema Imunitário/microbiologia , Filogenia , Homologia de Sequência de Aminoácidos , Virulência , Vírus/patogenicidade , beta-Defensinas/genética
19.
Zoo Biol ; 38(3): 305-315, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868683

RESUMO

Zoos have played a pivotal role in the successful reinforcement and reintroduction of species threatened with extinction, but prioritization is required in the face of increasing need and limited capacity. One means of prioritizing between species of equal threat status when establishing new breeding programs is the consideration of evolutionary distinctness (ED). More distinct species have fewer close relatives such that their extinction would result in a greater overall loss to the Tree of Life. Considering global ex situ holdings of birds (a group with a complete and well-detailed evolutionary tree), we investigate the representation of at-risk and highly evolutionarily distinct species in global zoo holdings. We identified a total of 2,236 bird species indicated by the Zoological Information Management System as being held in zoological institutions worldwide. As previously reported, imperiled species (defined as those possessing endangered or critically endangered threat status) in this database are less likely to be held in zoos than non-imperiled species. However, we find that species possessing ED scores within the top 10% of all bird species are more likely to be held in zoos than other species, possibly because they possess unique characteristics that have historically made them popular exhibits. To assist with the selection of high priority ED species for future zoo conservation programs, we provide a list of imperiled species currently not held in zoos, ranked by ED. This list highlights species representing particular priorities for ex situ conservation planners, and represents a practical tool for improving the conservation value of zoological collections.


Assuntos
Aves/classificação , Espécies em Perigo de Extinção , Filogenia , Animais , Animais de Zoológico , Aves/genética , Cruzamento , Conservação dos Recursos Naturais/métodos
20.
Nat Commun ; 10(1): 1275, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894527

RESUMO

Understanding non-crown dinosaur reproduction is hindered by a paucity of directly associated adults with reproductive traces. Here we describe a new enantiornithine, Avimaia schweitzerae gen. et sp. nov., from the Lower Cretaceous Xiagou Formation with an unlaid egg two-dimensionally preserved within the abdominothoracic cavity. Ground-sections reveal abnormal eggshell proportions, and multiple eggshell layers best interpreted as a multi-layered egg resulting from prolonged oviductal retention. Fragments of the shell membrane and cuticle are both preserved. SEM reveals that the cuticle consists of nanostructures resembling those found in neornithine eggs adapted for infection-prone environments, which are hypothesized to represent the ancestral avian condition. The femur preserves small amounts of probable medullary bone, a tissue found today only in reproductively active female birds. To our knowledge, no other occurrence of Mesozoic medullary bone is associated with indications of reproductive activity, such as a preserved egg, making our identification unique, and strongly supported.


Assuntos
Aves/anatomia & histologia , Dinossauros/anatomia & histologia , Casca de Ovo/anatomia & histologia , Fêmur/anatomia & histologia , Fósseis/anatomia & histologia , Reprodução/fisiologia , Animais , Evolução Biológica , Aves/classificação , Dinossauros/classificação , Extinção Biológica , Feminino , Fósseis/diagnóstico por imagem , Fósseis/história , História Antiga , Óvulo/citologia , Filogenia
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