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1.
Sci Adv ; 10(17): eadl5255, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38657058

RESUMO

Sex-limited polymorphism has evolved in many species including our own. Yet, we lack a detailed understanding of the underlying genetic variation and evolutionary processes at work. The brood parasitic common cuckoo (Cuculus canorus) is a prime example of female-limited color polymorphism, where adult males are monochromatic gray and females exhibit either gray or rufous plumage. This polymorphism has been hypothesized to be governed by negative frequency-dependent selection whereby the rarer female morph is protected against harassment by males or from mobbing by parasitized host species. Here, we show that female plumage dichromatism maps to the female-restricted genome. We further demonstrate that, consistent with balancing selection, ancestry of the rufous phenotype is shared with the likewise female dichromatic sister species, the oriental cuckoo (Cuculus optatus). This study shows that sex-specific polymorphism in trait variation can be resolved by genetic variation residing on a sex-limited chromosome and be maintained across species boundaries.


Assuntos
Polimorfismo Genético , Animais , Feminino , Masculino , Aves/genética , Fenótipo , Evolução Biológica , Pigmentação/genética , Caracteres Sexuais , Evolução Molecular
2.
Oecologia ; 204(1): 107-118, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38141067

RESUMO

Stable isotope analysis provides valuable insights into the ecology of long-distance migratory birds during periods spent away from a specific study site. In a previous study, Swedish great reed warblers (Acrocephalus arundinaceus) infected with haemosporidian parasites differed in feather isotope ratios compared to non-infected birds, suggesting that infected and non-infected birds spent the non-breeding season in different locations or habitats. Here, we use a novel dataset comprising geolocator data, isotopes, and haemosporidian infection status of 92 individuals from four Eurasian populations to investigate whether parasite transmission varies with geography or habitats. We found that the probability of harbouring Plasmodium and Leucocytozoon parasites was higher in birds moulting in the eastern region of the non-breeding grounds. However, no geographic pattern occurred for Haemoproteus infections or overall infection status. In contrast to the previous study, we did not find any relationship between feather isotope ratios and overall haemosporidian infection for the entire current dataset. Plasmodium-infected birds had lower feather δ15N values indicating that they occupied more mesic habitats. Leucocytozoon-infected birds had higher feather δ34S values suggesting more coastal sites or wetlands with anoxic sulphate reduction. As the composition and prevalence of haemosporidian parasites differed between the old and the current dataset, we suggest that the differences might be a consequence of temporal dynamics of haemosporidian parasites. Our results emphasize the importance of replicating studies conducted on a single population over a restricted time period, as the patterns can become more complex for data from wider geographical areas and different time periods.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Aves Canoras , Humanos , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Plumas , Muda , Isótopos , Aves Canoras/parasitologia , Prevalência , Filogenia
3.
Global Health ; 19(1): 52, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525178

RESUMO

BACKGROUND: Pandemics as health and humanitarian crises have exerted traceable impacts on food security. Almost all past and current pandemics have created a food crisis that affects a share of the global population and threaten global food security. With the more frequent outbreaks of emerging and re-emerging diseases or pandemics, this paper looks at the various types of impacts from the current coronavirus crisis and past pandemics to identify their major impact on food security. SCOPE: To this effect, key strategies that could be put in place to ensure the efficient resilience of food systems before, during, and after the pandemics to mitigate the negative impact of the pandemics on global food security are recommended. The most recent effects of the current coronavirus crisis have been disruptions in the flow of farm labourers and inefficient farm operations leading to postharvest food losses. KEY FINDINGS AND CONCLUSIONS: Modification of diets between social groups has also been observed. Future response orientations to prevent and mitigate the effects of pandemics on food security will consider pro-active and adapted policy, program, and institutional actions towards the systemic development of global food systems as an interconnected network.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle , SARS-CoV-2 , Surtos de Doenças , Segurança Alimentar
4.
Foods ; 12(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36900451

RESUMO

Wild mushroom foraging has a long tradition, especially in the region of Central Europe. Wild mushrooms are a valuable food resource, as they provide nutritional benefits to the European population. They offer a relatively high content of protein and are traditionally used in many European cuisines as a substitute for meat. This is particularly true in times of crisis, such as wars and pandemics. The study presented in this paper shows that wild mushrooms can substitute around 0.2 percent of daily protein intake and contribute around 3% to the agricultural output of the Czech economy, which was selected as a representative for Central Europe. The calculated real price of wild mushrooms indicates their increasing popularity as a source of food protein in Central Europe, while their price seems to be independent of the quantity supplied.

5.
J Anim Ecol ; 92(7): 1320-1331, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36411970

RESUMO

Climatic conditions affect animals but range-wide impacts at the population level remain largely unknown, especially in migratory species. However, studying climate-population relationships is still challenging in small migrants due to a lack of efficient and cost-effective geographic tracking method. Spatial distribution patterns of environmental stable isotopes (so called 'isoscapes') generally overcome these limitations but none of the currently available isoscapes provide a substantial longitudinal gradient in species-rich sub-Saharan Africa. In this region, sulphur (δ34 S) has not been sufficiently explored on a larger scale. We developed a δ34 S isoscape to trace animal origins in sub-Saharan Africa by coupling known-origin samples from tracked migratory birds with continental remotely sensed environmental data building on environment-δ34 S relationships using a flexible machine learning technique. Furthermore, we link population-specific nonbreeding grounds with interannual climatic variation that might translate to breeding population trends. The predicted δ34 S isotopic map featured east-west and coast-to-inland isotopic gradients and was applied to predict nonbreeding grounds of three breeding populations of Eurasian Reed Warblers Acrocephalus scirpaceus with two distinct migratory phenotypes. Breeding populations as well as migratory phenotypes exhibited large-scale segregation within the African nonbreeding range. These regions also differed substantially in the interannual climatic variation, with higher interannual variability in the eastern part of the range during 2001-2012. Over the same period, the eastern European breeding population seemed to have experienced a more steep decline in population size. The link between migratory patterns and large-scale climatic variability appears important to better understand population trajectories in many declining migratory animals. We believe animal tracing using sulphur isotopes will facilitate these efforts and offers manifold ecological and forensic applications in the biodiversity hotspot of sub-Saharan Africa.


Assuntos
Aves Canoras , Animais , Isótopos de Enxofre , Migração Animal , África , Densidade Demográfica , Estações do Ano
6.
Front Public Health ; 11: 1275287, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38332939

RESUMO

The public perspective on genetically modified foods (GMFs) has been intensely debated and scrutinized. Often, discussions surrounding GMF tend to revolve solely around the potential health risks associated with their consumption. However, it is essential to acknowledge that public perceptions of genetically modified foods are multifaceted, encompassing environmental concerns, ethical considerations, and economic implications. This paper studies the factors predicting GMF acceptance employing the representative sample of the Czech population (N = 884, aged 18-90 years, M ± SD: 48.17 ± 17.72; 53.40% women, 18.04% with higher education). The research relies on the Behavioral Change Model and the Health Belief Model. We employ hierarchical ordinal regressions to study the effects of information, environmental concerns, perceived health risks, food habits, purchasing habits, and socio-demographics on GMF acceptance. The results suggest that the (un)willingness to purchase GMF is primarily driven by the health risks - the environmental concerns were largely unimportant. The impact of information provision on GMF acceptance proved positive, suggesting information and education to be the main channels of creating public acceptance. The intrinsic interest regarding information related to GMF had an adverse impact on the perception of GMF morality. The benefits of the GMF proved unrelated to the GMF acceptance, indicating the gap in the information campaign. The research provides valuable insights for policymakers, public health professionals, and market researchers to communicate the GMF agenda effectively to the general public.


Assuntos
Alimentos Geneticamente Modificados , Humanos , Feminino , Masculino , Fator de Maturação da Glia , Comportamento do Consumidor , Escolaridade , Nível de Saúde
7.
Sustain Prod Consum ; 30: 752-760, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35071718

RESUMO

Currently, there is an alarming increase in food insecurity during the COVID-19 pandemic in many countries throughout the world. This will be seen particularly in the countries of the Global South (developing countries). Many countries are trying to show efforts to keep agriculture, food industry and markets running, the supply chains and access to the markets and affordable food is still not secured. Disruptions caused by the COVID-19 pandemic are going to/or already have affected the poor and other marginalised groups, mainly those with less purchasing power. It is necessary to mitigate the pandemic's impacts across the food system, enhance the resilience of food systems and avoid any potential food shortages. Therefore, this paper provides an overview of past pandemics and tries to synthesise the main lessons learned from these while also outlining visions of post-COVID-19 agriculture and the effects on food security.

8.
PLoS One ; 16(12): e0260601, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34905550

RESUMO

BACKGROUND AND AIMS: Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by disease-associated variants in the alpha-galactosidase A gene (GLA). FD is a known cause of stroke in younger patients. There are limited data on prevalence of FD and stroke risk in unselected stroke patients. METHODS: A prospective nationwide study including 35 (78%) of all 45 stroke centers and all consecutive stroke patients admitted during three months. Clinical data were collected in the RES-Q database. FD was diagnosed using dried blood spots in a stepwise manner: in males-enzymatic activity, globotriaosylsphingosine (lyso-Gb3) quantification, if positive followed by GLA gene sequencing; and in females GLA sequencing followed by lyso-Gb3. RESULTS: 986 consecutive patients (54% men, mean age 70 years) were included. Observed stroke type was ischemic 79%, transient ischemic attack (TIA) 14%, intracerebral hemorrhage (ICH) 7%, subarachnoid hemorrhage 1% and cerebral venous thrombosis 0.1%. Two (0.2%, 95% CI 0.02-0.7) patients had a pathogenic variant associated with the classical FD phenotype (c.1235_1236delCT and p.G325S). Another fourteen (1.4%, 95% CI 0.08-2.4) patients had a variant of GLA gene considered benign (9 with p.D313Y, one p.A143T, one p.R118C, one p.V199A, one p.R30K and one p.R38G). The index stroke in two carriers of disease-associated variant was ischemic lacunar. In 14 carriers of GLA gene variants 11 strokes were ischemic, two TIA, and one ICH. Patients with positive as compared to negative GLA gene screening were younger (mean 60±SD, min, max, vs 70±SD, min, max, P = 0.02), otherwise there were no differences in other baseline variables. CONCLUSIONS: The prevalence of FD in unselected adult patients with acute stroke is 0.2%. Both patients who had a pathogenic GLA gene variant were younger than 50 years. Our results support FD screening in patients that had a stroke event before 50 years of age.


Assuntos
Doença de Fabry/epidemiologia , Doença de Fabry/genética , Glicolipídeos/sangue , Esfingolipídeos/sangue , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/genética , alfa-Galactosidase/genética , Idoso , República Tcheca/epidemiologia , Teste em Amostras de Sangue Seco , Doença de Fabry/sangue , Doença de Fabry/complicações , Feminino , Expressão Gênica , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Prevalência , Estudos Prospectivos , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , alfa-Galactosidase/sangue
9.
Materials (Basel) ; 14(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279243

RESUMO

Because there is a lack of wood resources in many countries, this work focused on pulp and paper production from the waste and agricultural residues of non-wood plants. The work aimed to pulp the nitrate-alkaline of black mustard (Brassica Nigra L.) and camelina (Camelina Sativa L.). The black mustard and the camelina were selected due to the expanding planted areas of these crops in the Czech Republic. To characterize the chemical composition of black mustard and camelina, cellulose, lignin, ash, and extractives were determined. Raw alpha-cellulose, beta-cellulose, and gamma-cellulose were also measured. The results showed that the content of lignin in non-wood plants is lower than that in softwoods. The cooked pulp was characterized by the delignification degree-Kappa number. Additionally, handsheet papers were made for selected samples of pulp. The handsheet papers were characterized by tensile index, breaking length, and smoothness and compared with commonly available papers.

10.
Materials (Basel) ; 14(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33671951

RESUMO

Biobutanol is a renewable, less polluting, and potentially viable alternative fuel to conventional gasoline. Biobutanol can be produced from same sources as bioethanol, and it has many advantages over the widespread bioethanol. This paper systematically analyzes biobutanol fuel as an alternative to bioethanol in alcohol-gasoline mixtures and the physicochemical properties. Based on the conducted analyses, it was found that biobutanol mixtures have a more suitable behavior of vapor pressure without the occurrence of azeotrope, do not form a separate phase in lower temperature, it has higher energy density, but slightly reduce the octane number and a have higher viscosity. However, in general, biobutanol has many advantageous properties that could allow its use in gasoline engines instead of the commonly used bioethanol.

11.
Ecol Evol ; 11(2): 753-762, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33520163

RESUMO

How blood parasite infections influence the migration of hosts remains a lively debated issue as past studies found negative, positive, or no response to infections. This particularly applies to small birds, for which monitoring of detailed migration behavior over a whole annual cycle has been technically unachievable so far. Here, we investigate how bird migration is influenced by parasite infections. To this end, we tracked great reed warblers (Acrocephalus arundinaceus) with multisensor loggers, characterized general migration patterns as well as detailed flight bout durations, resting times and flight heights, and related these to the genus and intensity of their avian haemosporidian infections. We found migration distances to be shorter and the onset of autumn migration to be delayed with increasing intensity of blood parasite infection, in particular for birds with Plasmodium and mixed-genus infections. Additionally, the durations of migratory flight bout were prolonged for infected compared to uninfected birds. But since severely infected birds and particularly birds with mixed-genus infections had shorter resting times, initial delays seemed to be compensated for and the timing in other periods of the annual cycle was not compromised by infection. Overall, our multisensor logger approach revealed that avian blood parasites have mostly subtle effects on migratory performance and that effects can occur in specific periods of the year only.

12.
Foods ; 9(12)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339333

RESUMO

In this study, 15 selected bottled mineral waters from chosen European countries were tested for their mineral nutrient contents. In particular, six important nutrients (Ca2+, Mg2+, Na+, K+, HCO3-, Cl-) were measured using atomic absorption spectroscopy. The content of mineral nutrients in all sampled mineral waters were compared to their expected content based on the label. Consequently, their taste was evaluated by 60 trained panelists who participated in the sensory analysis. The results from both the atomic absorption spectroscopy and sensory analysis were analyzed using the regression framework. On the basis of the results from the regression analysis, we determined to what extent the individual mineral nutrients determined the taste of the mineral water. According to the regression results, four out of six analyzed nutrients had a measurable impact on taste. These findings can help producers to provide ideal, health-improving nutrients for mineral water buyers.

13.
Materials (Basel) ; 13(23)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261102

RESUMO

This article focuses on the issue of motor oils used in the engines of non-road mobile machinery (NRMM), more specifically tractors. The primary goal of the paper is to determine the appropriate replacement interval for these oils. The physical properties of the examined samples were first determined by conventional instruments. Furthermore, the concentrations of abrasive metals, contaminants, and additive elements were measured using an optical emission spectrometer. Lastly, the content of water, fuel, and glycol and the products of oxidation, nitration, and sulfation were determined by using infrared spectrometry. The measured values were compared to the limit values. Based on the processing and evaluation of these analyses, the overall condition of the oils was assessed and subsequently the optimal exchange interval of the examined oils was determined. In addition, a risk analysis of the outage was performed. Due to the high yields of crops, farmers can lose a significant amount of product when a tractor is not functioning during the harvest period. This loss is calculated in the paper.

14.
FEMS Microbiol Ecol ; 96(9)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32672792

RESUMO

An animal's gut microbiota (GM) is shaped by a range of environmental factors affecting the bacterial sources invading the host. At the same time, animal hosts are equipped with intrinsic mechanisms enabling regulation of GM. However, there is limited knowledge on the relative importance of these forces. To assess the significance of host-intrinsic vs environmental factors, we studied GM in nestlings of an obligate brood parasite, the common cuckoo (Cuculus canorus), raised by two foster species, great reed warblers (Acrocephalus arundinaceus) and Eurasian reed warblers (A. scirpaceus), and compared these with GM of the fosterers' own nestlings. We show that fecal GM varied between cuckoo and warbler nestlings when accounting for the effect of foster/parent species, highlighting the importance of host-intrinsic regulatory mechanisms. In addition to feces, cuckoos also expel a deterrent secretion, which provides protection against olfactory predators. We observed an increased abundance of bacterial genera capable of producing repulsive volatile molecules in the deterrent secretion. Consequently, our results support the hypothesis that microbiota play a role in this antipredator mechanism. Interestingly, fosterer/parent identity affected only cuckoo deterrent secretion and warbler feces microbiota, but not that of cuckoo feces, suggesting a strong selection of bacterial strains in the GM by cuckoo nestlings.


Assuntos
Microbioma Gastrointestinal , Microbiota , Parasitos , Passeriformes , Aves Canoras , Animais
15.
Naturwissenschaften ; 107(2): 12, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32108908

RESUMO

Several hypotheses have been proposed to explain the mechanisms responsible for maintenance of host-specific gentes in the common cuckoo (Cuculus canorus). Some of them expect that when adult cuckoos return to lay their eggs to their natal site (natal philopatry hypothesis) or habitat in which they were reared (habitat-imprinting hypothesis), there is a higher probability of finding nests of the host species by which they were reared. Since published evidence is ambiguous, we here evaluate the natal philopatry and habitat-imprinting hypotheses using information on habitat homogeneity and cross-continental long-term ringing data. We found no evidence for the natal philopatry hypothesis-instead of returning to their natal site, juvenile cuckoos exhibited longer dispersal movements than adults, and the difference was even larger in comparison with a wide array of cuckoo host species. On the contrary, we found support for the habitat-imprinting hypothesis-juvenile cuckoos followed similar levels of natal habitat homogeneity at 5- and 25-km scale when returning to breed in the next years. Our results suggest that preference for the particular habitat structures may help cuckoos to find appropriate hosts.


Assuntos
Aves/fisiologia , Ecossistema , Especificidade de Hospedeiro , Parasitos/fisiologia , Animais , Fixação Psicológica Instintiva
16.
Sci Rep ; 9(1): 20248, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882957

RESUMO

Each year, billions of songbirds cross large ecological barriers during their migration. Understanding how they perform this incredible task is crucial to predict how global change may threaten the safety of such journeys. Earlier studies based on radar suggested that most songbirds cross deserts in intermittent flights at high altitude, stopping in the desert during the day, while recent tracking with light loggers suggested diurnal prolongation of nocturnal flights and common non-stop flights for some species. We analyzed light intensity and temperature data obtained from geolocation loggers deployed on 130 individuals of ten migratory songbird species, and show that a large variety of strategies for crossing deserts exists between, but also sometimes within species. Diurnal stopover in the desert is a common strategy in autumn, while most species prolonged some nocturnal flights into the day. Non-stop flights over the desert occurred more frequently in spring than in autumn, and more frequently in foliage gleaners. Temperature recordings suggest that songbirds crossed deserts with flight bouts performed at various altitudes according to species and season, along a gradient ranging from low above ground in autumn to probably >2000 m above ground level, and possibly at higher altitude in spring. High-altitude flights are therefore not the general rule for crossing deserts in migrant songbirds. We conclude that a diversity of migration strategies exists for desert crossing among songbirds, with variations between but also within species.


Assuntos
Migração Animal/fisiologia , Clima Desértico , Meio Ambiente , Voo Animal/fisiologia , Aves Canoras/fisiologia , Altitude , Animais , Ritmo Circadiano/fisiologia , Sistemas de Informação Geográfica , Luz , Estações do Ano , Aves Canoras/classificação , Especificidade da Espécie , Temperatura , Fatores de Tempo
17.
ISME J ; 13(9): 2363-2376, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31127178

RESUMO

The functional relevance of microbiota is a key aspect for understanding host-microbiota interactions. Mammalian skin harbours a complex consortium of beneficial microorganisms known to provide health and immune-boosting advantages. As yet, however, little is known about functional microbial communities on avian feathers, including their co-evolution with the host and factors determining feather microbiota (FM) diversity. Using 16S rRNA profiling, we investigated how host species identity, phylogeny and geographic origin determine FM in free-living passerine birds. Moreover, we estimated the relative abundance of bacteriocin-producing bacteria (BPB) and keratinolytic feather damaging bacteria (FDB) and evaluated the ability of BPB to affect FM diversity and relative abundance of FDB. Host species identity was associated with feather bacterial communities more strongly than host geographic origin. FM functional properties differed in terms of estimated BPB and FDB relative abundance, with both showing interspecific variation. FM diversity was negatively associated with BPB relative abundance across species, whereas BPB and FDB relative abundance was positively correlated. This study provides the first thorough evaluation of antimicrobial peptides-producing bacterial communities inhabiting the feather integument, including their likely potential to mediate niche-competition and to be associated with functional species-specific feather microbiota in avian hosts.


Assuntos
Bactérias/isolamento & purificação , Bacteriocinas/biossíntese , Aves/microbiologia , Plumas/microbiologia , Microbiota , Animais , Bactérias/classificação , Bactérias/genética , Especificidade de Hospedeiro , Filogenia , RNA Ribossômico 16S/genética , Especificidade da Espécie
18.
Proc Biol Sci ; 286(1897): 20182821, 2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30963841

RESUMO

In many taxa, the most common form of sex-biased migration timing is protandry-the earlier arrival of males at breeding areas. Here we test this concept across the annual cycle of long-distance migratory birds. Using more than 350 migration tracks of small-bodied trans-Saharan migrants, we quantify differences in male and female migration schedules and test for proximate determinants of sex-specific timing. In autumn, males started migration about 2 days earlier, but this difference did not carry over to arrival at the non-breeding sites. In spring, males on average departed from the African non-breeding sites about 3 days earlier and reached breeding sites ca 4 days ahead of females. A cross-species comparison revealed large variation in the level of protandry and protogyny across the annual cycle. While we found tight links between individual timing of departure and arrival within each migration season, only for males the timing of spring migration was linked to the timing of previous autumn migration. In conclusion, our results demonstrate that protandry is not exclusively a reproductive strategy but rather occurs year-round and the two main proximate determinants for the magnitude of sex-biased arrival times in autumn and spring are sex-specific differences in departure timing and migration duration.


Assuntos
Migração Animal , Aves/fisiologia , África do Norte , Animais , Europa (Continente) , Feminino , Masculino , Reprodução , Estações do Ano , Fatores Sexuais , Aves Canoras/fisiologia
19.
R Soc Open Sci ; 5(1): 171675, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29410867

RESUMO

Migratory birds often move significantly within their non-breeding range before returning to breed. It remains unresolved under which circumstances individuals relocate, whether movement patterns are consistent between populations and to what degree the individuals benefit from the intra-tropical movement (ITM). We tracked adult great reed warblers Acrocephalus arundinaceus from a central and a southeastern European breeding population, which either stay at a single non-breeding site, or show ITM, i.e. move to a second site. We related ITM to the normalized difference vegetation index (NDVI) describing vegetation conditions and probably reflecting food abundance for these insectivorous birds. Three-quarters of birds showed ITM across the non-breeding range. We found no difference in range values and mean values of NDVI between the single non-breeding sites of stationary birds and the two sites of moving birds. The vegetation conditions were better at the second sites compared to the first sites during the period which moving birds spent at the first sites. Vegetation conditions further deteriorated at the first sites during the period the moving birds resided at their second sites. Our study provides evidence that birds probably benefit from improved conditions after ITM compared to the conditions at the sites from where they departed.

20.
Mol Ecol ; 26(19): 5292-5304, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28401612

RESUMO

Vertebrate gut microbiota (GM) is comprised of a taxonomically diverse consortium of symbiotic and commensal microorganisms that have a pronounced effect on host physiology, immune system function and health status. Despite much research on interactions between hosts and their GM, the factors affecting inter- and intraspecific GM variation in wild populations are still poorly known. We analysed data on faecal microbiota composition in 51 passerine species (319 individuals) using Illumina MiSeq sequencing of bacterial 16S rRNA (V3-V4 variable region). Despite pronounced interindividual variation, GM composition exhibited significant differences at the interspecific level, accounting for approximately 20%-30% of total GM variation. We also observed a significant correlation between GM composition divergence and host's phylogenetic divergence, with strength of correlation higher than that of GM vs. ecological or life history traits and geographic variation. The effect of host's phylogeny on GM composition was significant, even after statistical control for these confounding factors. Hence, our data do not support codiversification of GM and passerine phylogeny solely as a by-product of their ecological divergence. Furthermore, our findings do not support that GM vs. host's phylogeny codiversification is driven primarily through trans-generational GM transfer as the GM vs. phylogeny correlation does not increase with higher sequence similarity used when delimiting operational taxonomic units. Instead, we hypothesize that the GM vs. phylogeny correlation may arise as a consequence of interspecific divergence of genes that directly or indirectly modulate composition of GM.


Assuntos
Bactérias/classificação , Microbioma Gastrointestinal/genética , Passeriformes/microbiologia , Filogenia , Animais , República Tcheca , Fezes/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Passeriformes/classificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
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