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1.
Proc Natl Acad Sci U S A ; 119(35): e2122851119, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994656

RESUMO

Disease transmission prediction across wildlife is crucial for risk assessment of emerging infectious diseases. Susceptibility of host species to pathogens is influenced by the geographic, environmental, and phylogenetic context of the specific system under study. We used machine learning to analyze how such variables influence pathogen incidence for multihost pathogen assemblages, including one of direct transmission (coronaviruses and bats) and two vector-borne systems (West Nile Virus [WNV] and birds, and malaria and birds). Here we show that this methodology is able to provide reliable global spatial susceptibility predictions for the studied host-pathogen systems, even when using a small amount of incidence information (i.e., [Formula: see text] of information in a database). We found that avian malaria was mostly affected by environmental factors and by an interaction between phylogeny and geography, and WNV susceptibility was mostly influenced by phylogeny and by the interaction between geographic and environmental distances, whereas coronavirus susceptibility was mostly affected by geography. This approach will help to direct surveillance and field efforts providing cost-effective decisions on where to invest limited resources.


Assuntos
Animais Selvagens , Doenças Transmissíveis Emergentes , Suscetibilidade a Doenças , Animais , Animais Selvagens/parasitologia , Animais Selvagens/virologia , Doenças das Aves/epidemiologia , Doenças das Aves/transmissão , Quirópteros/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/veterinária , Coronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/veterinária , Bases de Dados Factuais , Meio Ambiente , Monitoramento Epidemiológico , Geografia , Interações Hospedeiro-Patógeno , Incidência , Aprendizado de Máquina , Malária/epidemiologia , Malária/transmissão , Malária/veterinária , Filogenia , Medição de Risco , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/transmissão , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental
2.
Proc Biol Sci ; 291(2018): 20232705, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38444334

RESUMO

The correct identification of variables affecting parasite diversity and assemblage composition at different spatial scales is crucial for understanding how pathogen distribution responds to anthropogenic disturbance and climate change. Here, we used a database of avian haemosporidian parasites to test how the taxonomic and phylogenetic diversity and phylogenetic structure of the genera Plasmodium, Haemoproteus and Leucocytozoon from three zoogeographic regions are related to surrogate variables of Earth's energy input, habitat heterogeneity (climatic diversity, landscape heterogeneity, host richness and human disturbance) and ecological interactions (resource use), which was measured by a novel assemblage-level metric related to parasite niche overlap (degree of generalism). We found that different components of energy input explained variation in richness for each genus. We found that human disturbance influences the phylogenetic structure of Haemoproteus while the degree of generalism explained richness and phylogenetic structure of Plasmodium and Leucocytozoon genera. Furthermore, landscape attributes related to human disturbance (human footprint) can filter Haemoproteus assemblages by their phylogenetic relatedness. Finally, assembly processes related to resource use within parasite assemblages modify species richness and phylogenetic structure of Plasmodium and Leucocytozoon assemblages. Overall, our study highlighted the genus-specific patterns with the different components of Earth's energy budget, human disturbances and degree of generalism.


Assuntos
Haemosporida , Especificidade de Hospedeiro , Humanos , Animais , Filogenia , Efeitos Antropogênicos , Aves
3.
Parasitology ; 149(8): 1129-1144, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35535473

RESUMO

Long-term, inter-annual and seasonal variation in temperature and precipitation influence the distribution and prevalence of intraerythrocytic haemosporidian parasites. We characterized the climatic niche behind the prevalence of the three main haemosporidian genera (Haemoproteus, Plasmodium and Leucocytozoon) in central-eastern Mexico, to understand their main climate drivers. Then, we projected the influence of climate change over prevalence distribution in the region. Using the MaxEnt modelling algorithm, we assessed the relative contribution of bioclimatic predictor variables to identify those most influential to haemosporidian prevalence in different avian communities within the region. Two contrasting climate change scenarios for 2070 were used to create distribution models to explain spatial turnover in prevalence caused by climate change. We assigned our study sites into polygonal operational climatic units (OCUs) and used the general haemosporidian prevalence for each OCU to indirectly measure environmental suitability for these parasites. A high statistical association between global prevalence and the bioclimatic variables 'mean diurnal temperature range' and 'annual temperature range' was found. Climate change projections for 2070 showed a significant modification of the current distribution of suitable climate areas for haemosporidians in the study region.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Mudança Climática , México/epidemiologia , Filogenia , Prevalência
4.
J Anim Ecol ; 89(8): 1754-1765, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32198927

RESUMO

Traditionally, most studies have described the organization of host-parasite interaction networks by considering only few host groups at limited geographical extents. However, host-parasite relationships are merged within different taxonomic groups and factors shaping these interactions likely differ between host and parasite groups, making group-level differences important to better understand the ecological and evolutionary dynamics of these interactive communities. Here we used a dataset of 629 ectoparasite species and 251 species of terrestrial mammals, comprising 10 orders distributed across the Nearctic and Neotropical regions of Mexico to assess the species-level drivers of mammalian ectoparasite faunas. Specifically, we evaluated whether body weight, geographical range size and within-range mammal species richness (i.e. diversity field) predict mammal ectoparasite species richness (i.e. degree centrality) and their closeness centrality within the mammal-ectoparasite network. In addition, we also tested if the observed patterns differ among mammal orders and if taxonomic closely related host mammals could more likely share the same set of ectoparasites. We found that ectoparasite species richness of small mammals (mainly rodents) with large proportional range sizes was high compared to large-bodied mammals, whereas the diversity field of mammals had no predictive value (except for bats). We also observed that taxonomic proximity was a main determinant of the probability to share ectoparasite species. Specifically, the probability to share ectoparasites in congeneric species reached up to 90% and decreased exponentially as the taxonomic distance increased. Further, we also detected that some ectoparasites are generalists and capable to infect mammalian species across different orders and that rodents have a remarkable role in the network structure, being closely connected to many other taxa. Hence, because many rodent species have synanthropic habits they could act as undesired reservoirs of disease agents for humans and urban animals. Considering the reported worldwide phenomenon of the proliferation of rodents accompanying the demographic decrease or even local extinction of large-bodied mammal species, these organisms may already be an increasing health threat in many regions of the world.


Assuntos
Ectoparasitoses , Parasitos , Doenças dos Roedores , Animais , Ectoparasitoses/veterinária , Interações Hospedeiro-Parasita , Mamíferos , México , Doenças dos Roedores/epidemiologia , Roedores
5.
BMC Ecol ; 20(1): 47, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814584

RESUMO

BACKGROUND: Forest habitats are important biodiversity refuges for a wide variety of bird species. Parasitism may modulate host species presence and abundance, and parasite effects can change according to forest management practices. Such processes are not well studied in vector-borne avian haemosporidians. We analyzed the effects of forest management on bird-dipteran-haemosporidian interactions, using seven common bird species in managed and unmanaged beech forest habitats in northeastern Germany. We assumed that forest structural heterogeneity affects parasite population parameters in avian hosts (i.e., prevalence and parasitemia), through its effect on the condition of the avian host but also through varying vector abundances. RESULTS: Parasite prevalence was high (about 80%) and homogeneous across different beech forest categories (i.e., young, old, unmanaged) and for all bird species, except Erithacus rubecula (35%). Parasitemia varied across bird species but not across forest categories within each avian species (lowest parasitemia were found in E. rubecula, Turdus merula, and Turdus philomelos). In our study system, we found that vector abundance was not the main driver of parasite dynamics. We found that forest structure affects parasite infection probability directly and potentially host condition via available resources that have to be used either to combat infections (i.e., high parasitemia) or to maintain a good body condition. CONCLUSIONS: The effects of each of the predictors were bird species-specific, and we found that Diptera vectors were not the foremost influence in our host-vector-parasite system. Effects of forest habitat variables indicated that for most bird species in this study, habitat regulation of infection probability was more likely (i.e., E. rubecula, Fringilla coelebs, Sylvia atricapilla), whereas for Parus major habitat characteristics impacted first individuals' body condition and subsequently the probability of infection. Our findings emphasize the need of species-specific analyses and to use continuous forest structural parameters (e.g., the proportion of gap, south facing aspect) to better understand habitat and land use effects on host-vector-parasite dynamics.


Assuntos
Haemosporida , Parasitos , Passeriformes , Animais , Florestas , Alemanha
6.
Cladistics ; 35(4): 446-460, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34633722

RESUMO

Neotropical seasonally dry forests (NSDFs) are widely distributed and possess high levels of species richness and endemism; however, their biogeography remains only partially understood. Using species distribution modelling and parsimony analysis of endemicity, we analysed the distributional patterns of the NSDF avifauna in order to identify their areas of endemism and provide a better understanding of the historical relationships among those areas. The strict consensus trees revealed 17 areas of endemism for NSDFs, which involve four large regions: Baja California, Caribbean-Antilles islands, Mesoamerica and South America. These well-resolved clades are circumscribed by geographical and ecological barriers associated with the Gulf of California, the leading edge of the Caribbean plate, the Tehuantepec Isthmus, the Polochic-Motagua fault, the Nicaragua Depression, the Chocó forest, the Amazon basin and the Andean Cordillera. Relationships among groups of NSDFs found here suggest that evolution of their avifauna involved a mixture of vicariance and dispersal events. Our results support the idea of independent diversification patterns and biogeographical processes in each region, including those previously associated with the Pleistocene Arc Hypothesis for NSDFs of south-eastern South America. This study provides a biogeographical framework to open new lines of research related to the biotic diversification of NSDFs.

7.
Virus Genes ; 54(6): 818-822, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30238313

RESUMO

Adenoviruses are important pathogens known to infect vertebrate hosts, including a wide range of primates. Despite its importance, data on the diversity of these viruses in non-human primates living in their natural habitat remain scarce. In this study, we conducted a surveillance of adenoviral infection in wild black howler monkeys from two protected natural areas in Mexico. This was achieved by analyzing 67 fecal samples using a nested PCR that targets the adenovirus DNA polymerase gene. Adenoviral DNA was detected in 12 samples from both study sites, with an overall prevalence of 17.9%. The amplified DNA sequences shared 100% nucleotide identity and phylogenetic analyses revealed that the haplotype detected was novel, and clustered with Platyrrhini mastadenovirus A, which was previously described in captive New World monkeys. Our data, along with the previous evidence, confirm that monkeys native to the Americas are the original hosts of these adenoviruses.


Assuntos
Infecções por Adenoviridae/veterinária , Adenoviridae/genética , Alouatta/virologia , Doenças dos Macacos/diagnóstico , Doenças dos Macacos/virologia , Adenoviridae/classificação , Animais , Feminino , Masculino , Doenças dos Macacos/epidemiologia , Filogenia
8.
Entropy (Basel) ; 20(8)2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-33265643

RESUMO

A Toda-chain symmetry is shown to underlie the van der Waals gas and its close cousin, the ideal gas. Links to contact geometry are explored.

9.
Glob Chang Biol ; 22(1): 364-79, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26367278

RESUMO

Assuming that co-distributed species are exposed to similar environmental conditions, ecological niche models (ENMs) of bird and plant species inhabiting tropical dry forests (TDFs) in Mexico were developed to evaluate future projections of their distribution for the years 2050 and 2070. We used ENM-based predictions and climatic data for two Global Climate Models, considering two Representative Concentration Pathway scenarios (RCP4.5/RCP8.5). We also evaluated the effects of habitat loss and the importance of the Mexican system of protected areas (PAs) on the projected models for a more detailed prediction of TDFs and to identify hot spots that require conservation actions. We identified four major distributional areas: the main one located along the Pacific Coast (from Sonora to Chiapas, including the Cape and Bajío regions, and the Balsas river basin), and three isolated areas: the Yucatán peninsula, central Veracruz, and southern Tamaulipas. When considering the effect of habitat loss, a significant reduction (~61%) of the TDFs predicted area occurred, whereas climate-change models suggested (in comparison with the present distribution model) an increase in area of 3.0-10.0% and 3.0-9.0% for 2050 and 2070, respectively. In future scenarios, TDFs will occupy areas above its current average elevational distribution that are outside of its present geographical range. Our findings show that TDFs may persist in Mexican territory until the middle of the XXI century; however, the challenges about long-term conservation are partially addressed (only 7% unaffected within the Mexican network of PAs) with the current Mexican PAs network. Based on our ENM approach, we suggest that a combination of models of species inhabiting present TDFs and taking into account change scenarios represent an invaluable tool to create new PAs and ecological corridors, as a response to the increasing levels of habitat destruction and the effects of climate change on this ecosystem.


Assuntos
Aves , Mudança Climática , Conservação dos Recursos Naturais/métodos , Florestas , Plantas , Animais , Ecossistema , México , Clima Tropical
10.
Methods Enzymol ; 697: 269-291, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38816126

RESUMO

The design of small peptides that assemble into catalytically active intermolecular structures has proven to be a successful strategy towards developing minimalistic catalysts that exhibit some of the unique functional features of enzymes. Among these, catalytic amyloids have emerged as a fruitful source to unravel many different activities. These assemblies can potentially have broad applications that range from biotechnology to prebiotic chemistry. Although many peptides that assemble into catalytic amyloids have been developed in recent years, the elucidation of convergent mechanistic aspects of the catalysis and the structure/function relationship is still a challenge. Novel catalytic activities are necessary to better address these issues and expand the current repertoire of applicability. In this chapter, we described a methodology to produce catalytic amyloids that are specifically active towards the hydrolysis of phosphoanhydride bonds of nucleotides. The design of potentially active amyloid-prone peptide sequences is explored using as template the active site of enzymes with nucleotidyltransferase activity. The procedures include an approach for sequence design, in vitro aggregation assays, morphological characterization of the amyloid state and a comprehensive methodology to measure activity in vitro using nucleoside and deoxynucleosides triphosphates as model substrates. The proposed strategy can also be implemented to explore different types of activities for the design of future catalytic amyloids.


Assuntos
Amiloide , Nucleotídeos , Hidrólise , Amiloide/química , Amiloide/metabolismo , Nucleotídeos/química , Nucleotídeos/metabolismo , Domínio Catalítico , Sequência de Aminoácidos , Catálise , Biocatálise
11.
Sci Total Environ ; 912: 168958, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38029979

RESUMO

Groundwater storage changes in the Amazon River Basin (ARB) play an important role in the hydrological behavior of the region, with significant influence on climate variability and rainforest ecosystems. The GRACE and GRACE-FO satellite missions provide gravity anomalies from which it is possible to monitor changes in terrestrial water storage, albeit at low spatial resolution. This study downscaled GRACE and GRACE-FO data from machine learning models from 1° (110 km approx) to 0.25° (27.5 km approx). It estimated the spatiotemporal variability of terrestrial and groundwater storage anomalies between 2002 and 2021 for the Amazon River Basin. In parallel, the Random Forest and AdaBoost algorithms were compared and analyzed. The results reflected a good fit of the models with a very low error and a slight superiority in the predictions obtained by AdaBoost. On the predictions at 0.25°, spatial patterns associated with the strong influence on storage changes of some rivers and snow-capped mountains were identified, as well as an increase in the accuracy of the scaled data of the original ones. Positive long-term behavior was also obtained in terrestrial and groundwater storage of 14.26 ± 1.18 km3/yr and + 22.24 ± 1.18 km3/yr, respectively. Validation of the time series of groundwater anomalies to water levels in the monitoring wells obtained maximum correlation coefficients of 0.85 with confidence levels of 0.01. These results are promising for satellite information in water management, especially in regional monitoring of unconfined aquifers. The obtained data is stored in a dedicated repository (Satizábal-Alarcón et al., 2023).

12.
Int J Parasitol Parasites Wildl ; 25: 100989, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39323907

RESUMO

The Wildlife Malaria Network (WIMANET) is a groundbreaking multinational collaboration focused on studying vector-borne haemosporidian parasites in wildlife. Unlike human malaria, wildlife malaria is found on all continents except Antarctica, with parasites being transmitted by a range of vectors. The complexity and diversity of these parasites makes it necessary to have an interdisciplinary approach to understand and mitigate their impacts. Established in 2023 within the framework of COST-Action (European Cooperation in Science and Technology), WIMANET unites researchers from diverse scientific backgrounds to tackle critical questions about wildlife malaria on a global scale. This meeting report summarises the activities and plans resulting from the 1st meeting of WIMANET's six working groups, spanning the genetic and morphological identification of parasites to understanding the drivers of host-parasite-vector associations from individual to community levels. WIMANET's collaborative efforts aim to fill the knowledge gaps and foster large-scale research initiatives transcending local and regional boundaries.

13.
Parasitology ; 140(14): 1799-810, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23981661

RESUMO

Culicoides vectors can transmit a diverse array of parasites and are globally distributed. We studied feeding preferences and seasonal variation of Culicoides (Diptera: Ceratopogonidae) vectors in an urban forest of Germany to determine whether humans living nearby are readily exposed to vector-borne parasites from wild animals. We used a fragment of the mtDNA COI gene to identify hosts from blood meals. We amplified a fragment of the mtDNA cyt b to detect haemosporidian infections in Culicoides abdomens and thoraxes. We detected a total of 22 Culicoides species. Fifty-eight blood meals (84%) were from humans, 10 from birds, and one from livestock. We found Culicoides kibunensis (considered ornithophilic) with 29 human blood meals. Host generalist Culicoides festivipennis and Culicoides obsoletus had 14 human blood meals. Culicoides clastrieri and Culicoides semimaculatus fed on birds; previously humans were their only known host. Six thoraxes and three abdomens were infected with either Haemoproteus pallidulus or Haemoproteus parabelopolskyi. There were changes in Culicoides community structure across months. Culicoides pictipennis was the dominant species during spring, C. kibunensis and C. clastrieri were dominant during summer, and C. obsoletus was dominant by early autumn. All dominant species were generalists feeding on birds, livestock and humans. Our results indicate that humans can serve as a blood source for dominant Culicoides species instead of the normal wild animal hosts in urban areas.


Assuntos
Doenças das Aves/parasitologia , Ceratopogonidae/fisiologia , Comportamento Alimentar/fisiologia , Haemosporida/isolamento & purificação , Insetos Vetores/fisiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/epidemiologia , Aves , Ceratopogonidae/classificação , Cidades , Alemanha/epidemiologia , Humanos , Insetos Vetores/classificação , Infecções Protozoárias em Animais/epidemiologia , Estações do Ano , Árvores , Zoonoses
14.
Plants (Basel) ; 12(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37653934

RESUMO

Climate change is expected to impact both the population structure and geographic distribution of plants. Species distribution models are widely used to assess range shifts and the vulnerability of plants to climate change. Despite the abundance of modeling studies, little is known about how existing populations respond to climate change. We investigated the demographic structure and vulnerability to climate change in Anemone moorei, a sub-shrub with a highly restricted distribution in a biodiversity hotspot. We improved the distribution knowledge through intensive field work. We conducted a census of stem length as a proxy for age for all known populations. We used ensemble forecasting to project distributions considering 10 future climate scenarios and developed a novel climate change vulnerability index for the species' distribution. We found that the mean stem length decreases and the proportion of young plants increases, while the size of fruiting plants decreases as A. moorei faces greater climate change vulnerability. We interpret these results as evidence for the onset of recent adaptation to climate change, consisting of reduced adult longevity and an earlier onset of reproduction. As a result of these changes, the proportion of juveniles in the population increases.

15.
J Vector Ecol ; 49(1): 1-14, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38147297

RESUMO

Because the vertical distribution and diversity of blood-sucking flies are poorly known, we determined the diversity, structure, and composition of culicids between vertical vegetation strata. We evaluated the influence of microclimatic variables during different times of the day over a year. We used eight CDC traps baited with CO2 at a height of 1.5 m and 12-15 m. We conducted rank-abundance curves, similarity analysis (ANOSIM and SIMPER), and multivariate clustering with incidence and abundance data. We used GAM models to analyze the influence of strata (understory vs canopy), humidity, and temperature on insect richness and abundance. During the day, the difference between strata was mainly due to higher abundance of Wyeomyia arthrostigma and Wyeomyia ca. adelpha in the understory. During the night, the differences were mainly due to higher abundance of Culex stigmatosoma, Culex salinarius, and Aedes allotecnon in the canopy, and Wyeomyia arthrostigma in the understory. Seasonality played a role in the similarity between the strata. Diversity during the day was positively related to humidity and temperature, and nocturnal diversity increased with temperature but decreased with higher humidity. The effects of environmental factors on the spatiotemporal distribution of fly species are essential for epidemiological surveillance.


Assuntos
Ceratopogonidae , Culex , Culicidae , Animais , Umidade , México , Temperatura , Florestas
16.
Drug Deliv Transl Res ; 12(11): 2740-2750, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35284985

RESUMO

Two pegylated lipid nanocapsules for triamcinolone transdermal delivery were designed. Both present a size close to 50 nm and a single monomodal distribution in particle size (PI < 0.2), with a zeta potential of - 20 ± 2 and + 18 ± 1, respectively. The triamcinolone encapsulation efficacy varied between 68 and 80%. They proved to be stable under storage conditions (4 °C) for at least 6 months and at a physiological temperature, using different media, for 48 h. Also, they were shown not to affect cell viability at the concentrations used. For ex vivo transdermal experiments, newborn pig skin was used. With respect to the triamcinolone transdermal penetration, the nanocapsules were demonstrated to have an absorption promoting effect, both when the drug nanocapsules were in solution or loaded into the hydrogel, quantifying between 2 and 15 times more absorbed drug than the control. In addition, regarding the triamcinolone retained in the skin, it is observed that lipid nanocapsules act as triamcinolone promoters when the nanosystems were in solution and when they were included in the hydrogel. This vehicle showed a greater triamcinolone reservoir effect in comparison to the nanocapsules, proving to be a good vehicle to formulate triamcinolone transdermal delivery.


Assuntos
Nanocápsulas , Animais , Hidrogéis , Lipídeos , Tamanho da Partícula , Polietilenoglicóis , Suínos , Triancinolona
17.
Ecol Evol ; 12(11): e9474, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36381388

RESUMO

The South American temperate forests were subjected to drastic topographic and climatic changes during the Pliocene-Pleistocene as a consequence of the Andean orogeny and glacial cycles. Such changes are common drivers of genetic structure and adaptation. Embothrium coccineum (Proteaceae) is an emblematic tree of the South American temperate forest (around 20°S of latitude) that has strongly been affected by topographic and climatic events. Previous studies have shown a marked genetic structure in this species, and distinct ecotypes have been described. Yet, little is known about their adaptive genetic responses. The main goal of this study was to investigate the effects of historical and contemporary landscape features affecting the genetic diversity and connectivity of E. coccineum throughout its current natural distribution. Using over 2000 single nucleotide polymorphisms (SNPs), we identified two genetic groups (a Northern and a Central-Southern group) that diverged around 2.8 million years ago. The level of genetic structure was higher among populations within the Northern genetic group than within the Central-Southern group. We propose that these differences in genetic structure may be due to differences in the assemblages of pollinators and in the evolutionary histories of the two genetic groups. Moreover, the data displayed a strong pattern of isolation by the environment in E. coccineum, suggesting that selection could have led to adaptive divergence among localities. We propose that in the Chilean temperate forest, the patterns of genetic variation in E. coccineum reflect both a Quaternary phylogenetic imprint and signatures of selection as a consequence of a strong environmental gradient.

18.
J Biogeogr ; 49(8): 1420-1442, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36247109

RESUMO

Aim: Climate change is expected to impact mountain biodiversity by shifting species ranges and the biomes they shape. The extent and regional variation in these impacts are still poorly understood, particularly in the highly biodiverse Andes. Regional syntheses of climate change impacts on vegetation are pivotal to identify and guide research priorities. Here we review current data, knowledge and uncertainties in past, present and future climate change impacts on vegetation in the Andes. Location: Andes. Taxon: Plants. Methods: We (i) conducted a literature review on Andean vegetation responses to past and contemporary climatic change, (ii) analysed future climate projections for different elevations and slope orientations at 19 Andean locations using an ensemble of model outputs from the Coupled Model Intercomparison Project 5, and (iii) calculated changes in the suitable climate envelope area of Andean biomes and compared these results to studies that used species distribution models. Results: Future climatic changes (2040-2070) are projected to be stronger at high-elevation areas in the tropical Andes (up to 4°C under RCP 8.5), while in the temperate Andes temperature increases are projected to be up to 2°C. Under this worst-case scenario, temperate deciduous forests and the grasslands/steppes from the Central and Southern Andes are predicted to show the greatest losses of suitable climatic space (30% and 17%-23%, respectively). The high vulnerability of these biomes contrasts with the low attention from researchers modelling Andean species distributions. Critical knowledge gaps include a lack of an Andean wide plant checklist, insufficient density of weather stations at high-elevation areas, a lack of high-resolution climatologies that accommodates the Andes' complex topography and climatic processes, insufficient data to model demographic and ecological processes, and low use of palaeo data for distribution modelling. Main conclusions: Climate change is likely to profoundly affect the extent and composition of Andean biomes. Temperate Andean biomes in particular are susceptible to substantial area contractions. There are, however, considerable challenges and uncertainties in modelling species and biome responses and a pressing need for a region-wide approach to address knowledge gaps and improve understanding and monitoring of climate change impacts in these globally important biomes.

19.
PLoS One ; 17(8): e0268161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35998118

RESUMO

Great-tailed Grackles (Quiscalus mexicanus) are a social, polygamous bird species whose populations have rapidly expanded their geographic range across North America over the past century. Before 1865, Great-tailed Grackles were only documented in Central America, Mexico, and southern Texas in the USA. Given the rapid northern expansion of this species, it is relevant to study its role in the dynamics of avian blood parasites. Here, 87 Great-tailed grackles in Arizona (a population in the new center of the range) were screened for haemosporidian parasites using microscopy and PCR targeting the parasite mitochondrial cytochrome b gene. Individuals were caught in the wild from January 2018 until February 2020. Haemosporidian parasite prevalence was 62.1% (54/87). A high Plasmodium prevalence was found (60.9%, 53/87), and one grackle was infected with Haemoproteus (Parahaemoproteus) sp. (lineage SIAMEX01). Twenty-one grackles were infected with P. cathemerium, sixteen with P. homopolare, four with P. relictum (strain GRW04), and eleven with three different genetic lineages of Plasmodium spp. that have not been characterized to species level (MOLATE01, PHPAT01, and ZEMAC01). Gametocytes were observed in birds infected with three different Plasmodium lineages, revealing that grackles are competent hosts for some parasite species. This study also suggests that grackles are highly susceptible and develop chronic infections consistent with parasite tolerance, making them competent to transmit some generalist haemosporidian lineages. It can be hypothesized that, as the Great-tailed Grackle expands its geographic range, it may affect local bird communities by increasing the transmission of local parasites but not introducing new species into the parasite species pool.


Assuntos
Doenças das Aves , Haemosporida , Malária Aviária , Parasitos , Passeriformes , Plasmodium , Animais , Doenças das Aves/epidemiologia , Haemosporida/genética , Humanos , Malária Aviária/epidemiologia , Filogenia , Plasmodium/genética , Prevalência , Texas
20.
Front Vet Sci ; 8: 604560, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33778034

RESUMO

Many human emergent and re-emergent diseases have a sylvatic cycle. Yet, little effort has been put into discovering and modeling the wild mammal reservoirs of dengue (DENV), particularly in the Americas. Here, we show a species-level susceptibility prediction to dengue of wild mammals in the Americas as a function of the three most important biodiversity dimensions (ecological, geographical, and phylogenetic spaces), using machine learning protocols. Model predictions showed that different species of bats would be highly susceptible to DENV infections, where susceptibility mostly depended on phylogenetic relationships among hosts and their environmental requirement. Mammal species predicted as highly susceptible coincide with sets of species that have been reported infected in field studies, but it also suggests other species that have not been previously considered or that have been captured in low numbers. Also, the environment (i.e., the distance between the species' optima in bioclimatic dimensions) in combination with geographic and phylogenetic distance is highly relevant in predicting susceptibility to DENV in wild mammals. Our results agree with previous modeling efforts indicating that temperature is an important factor determining DENV transmission, and provide novel insights regarding other relevant factors and the importance of considering wild reservoirs. This modeling framework will aid in the identification of potential DENV reservoirs for future surveillance efforts.

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