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1.
Epidemiol Infect ; 148: e209, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32912363

RESUMO

Ecologic studies investigating COVID-19 mortality determinants, used to make predictions and design public health control measures, generally focused on population-based variable counterparts of individual-based risk factors. Influenza is not causally associated with COVID-19, but shares population-based determinants, such as similar incidence/mortality trends, transmission patterns, efficacy of non-pharmaceutical interventions, comorbidities and underdiagnosis. We investigated the ecologic association between influenza mortality rates and COVID-19 mortality rates in the European context. We considered the 3-year average influenza (2014-2016) and COVID-19 (31 May 2020) crude mortality rates in 34 countries using EUROSTAT and ECDC databases and performed correlation and regression analyses. The two variables - log transformed, showed significant Spearman's correlation ρ = 0.439 (P = 0.01), and regression coefficients, b = 0.743 (95% confidence interval, 0.272-1.214; R2 = 0.244; P = 0.003), b = 0.472 (95% confidence interval, 0.067-0.878; R2 = 0.549; P = 0.02), unadjusted and adjusted for confounders (population size and cardiovascular disease mortality), respectively. Common significant determinants of both COVID-19 and influenza mortality rates were life expectancy, influenza vaccination in the elderly (direct associations), number of hospital beds per population unit and crude cardiovascular disease mortality rate (inverse associations). This analysis suggests that influenza mortality rates were independently associated with COVID-19 mortality rates in Europe, with implications for public health preparedness, and implies preliminary undetected SARS-CoV-2 spread in Europe.


Assuntos
Betacoronavirus , Infecções por Coronavirus/mortalidade , Influenza Humana/mortalidade , Pneumonia Viral/mortalidade , Ecologia , Europa (Continente)/epidemiologia , Humanos , Pandemias
2.
Nat Commun ; 11(1): 4717, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948774

RESUMO

Unraveling the drivers controlling community assembly is a central issue in ecology. Although it is generally accepted that selection, dispersal, diversification and drift are major community assembly processes, defining their relative importance is very challenging. Here, we present a framework to quantitatively infer community assembly mechanisms by phylogenetic bin-based null model analysis (iCAMP). iCAMP shows high accuracy (0.93-0.99), precision (0.80-0.94), sensitivity (0.82-0.94), and specificity (0.95-0.98) on simulated communities, which are 10-160% higher than those from the entire community-based approach. Application of iCAMP to grassland microbial communities in response to experimental warming reveals dominant roles of homogeneous selection (38%) and 'drift' (59%). Interestingly, warming decreases 'drift' over time, and enhances homogeneous selection which is primarily imposed on Bacillales. In addition, homogeneous selection has higher correlations with drought and plant productivity under warming than control. iCAMP provides an effective and robust tool to quantify microbial assembly processes, and should also be useful for plant and animal ecology.


Assuntos
Ecologia , Aquecimento Global , Pradaria , Microbiota , Animais , Bactérias/classificação , Biodiversidade , Secas , Modelos Biológicos , Filogenia , Sensibilidade e Especificidade
3.
Mar Environ Res ; 160: 105051, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907717

RESUMO

In order to detect the possible regulatory effect of non-native C. gigas on the native O. edulis, under aquaculture conditions, feeding interactions between them were investigated in a highly productive environment of Lim Bay (Adriatic Sea). The present study uses a multi-methodological approach, including stomach content, DNA barcoding and stable isotope analysis to elucidate the feeding ecology of two oyster species. The research confirmed a high overlap throughout the year in the feeding traits among native and non-native oyster species. Competition for food was not the only relationship that exists between the investigated species as the presence of O. edulis larvae in C. gigas stomach content was confirmed by DNA analysis. Findings are not in favour of introducing C. gigas to commercial aquaculture in any new areas in the Adriatic Sea and support the need to improve the existing O. edulis aquaculture and conserve its wild stocks.


Assuntos
Aquicultura , Crassostrea , Comportamento Alimentar , Ostrea , Animais , Ecologia , Cadeia Alimentar , Larva
5.
PLoS One ; 15(8): e0236920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745085

RESUMO

BACKGROUND: Twenty-seven villages were selected in southwest Burkina Faso to implement new vector control strategies in addition to long lasting insecticidal nets (LLINs) through a Randomized Controlled Trial (RCT). We conducted entomological surveys in the villages during the dry cold season (January 2017), dry hot season (March 2017) and rainy season (June 2017) to describe malaria vectors bionomics, insecticide resistance and transmission prior to this trial. METHODS: We carried out hourly catches (from 17:00 to 09:00) inside and outside 4 houses in each village using the Human Landing Catch technique. Mosquitoes were identified using morphological taxonomic keys. Specimens belonging to the Anopheles gambiae complex and Anopheles funestus group were identified using molecular techniques as well as detection of Plasmodium falciparum infection and insecticide resistance target-site mutations. RESULTS: Eight Anopheles species were detected in the area. Anopheles funestus s.s was the main vector during the dry cold season. It was replaced by Anopheles coluzzii during the dry hot season whereas An. coluzzii and An. gambiae s.s. were the dominant species during the rainy season. Species composition of the Anopheles population varied significantly among seasons. All insecticide resistance mechanisms (kdr-w, kdr-e and ace-1 target site mutations) investigated were found in each members of the An. gambiae complex but at different frequencies. We observed early and late biting phenotypes in the main malaria vector species. Entomological inoculation rates were 2.61, 2.67 and 11.25 infected bites per human per month during dry cold season, dry hot season and rainy season, respectively. CONCLUSION: The entomological indicators of malaria transmission were high despite the universal coverage with LLINs. We detected early and late biting phenotypes in the main malaria vector species as well as physiological insecticide resistance mechanisms. These data will be used to evaluate the impact of complementary tools to LLINs in an upcoming RCT.


Assuntos
Anopheles , Resistência a Inseticidas/genética , Malária Falciparum/transmissão , Mosquitos Vetores/genética , Animais , Anopheles/classificação , Anopheles/genética , Anopheles/parasitologia , Burkina Faso/epidemiologia , Culex/classificação , Culex/genética , Culex/parasitologia , Culicidae/classificação , Culicidae/genética , Culicidae/parasitologia , Ecologia , Genótipo , Humanos , Malária Falciparum/prevenção & controle , Controle de Mosquitos/métodos , Controle de Mosquitos/organização & administração , Mosquitos Vetores/classificação , Mosquitos Vetores/parasitologia , Plasmodium falciparum/isolamento & purificação , Estações do Ano
6.
BMC Ecol ; 20(1): 42, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32762674

RESUMO

The seventh BMC Ecology competition attracted entries from talented ecologists from around the world. Together, they showcase the beauty and diversity of life on our planet as well as providing an insight into the biological interactions found in nature. This editorial celebrates the winning images as selected by the Editor of BMC Ecology and senior members of the journal's editorial board. Enjoy!


Assuntos
Ecologia
7.
Nat Commun ; 11(1): 4088, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796849

RESUMO

Most marine fish species express life-history changes across temperature gradients, such as faster growth, earlier maturation, and higher mortality at higher temperature. However, such climate-driven effects on life histories and population dynamics remain unassessed for most fishes. For 332 Indo-Pacific fishes, we show positive effects of temperature on body growth (but with decreasing asymptotic length), reproductive rates (including earlier age-at-maturation), and natural mortality for all species, with the effect strength varying among habitat-related species groups. Reef and demersal fishes are more sensitive to temperature changes than pelagic and bathydemersal fishes. Using a life table, we show that the combined changes of life histories upon increasing temperature tend to facilitate population growth for slow life-history populations, but reduce it for fast life-history ones. Within our data, lower proportions (25-30%) of slow life-history fishes but greater proportions of fast life-history fishes (42-60%) show declined population growth rates under 1 °C warming. Together, these findings suggest prioritizing sustainable management for fast life-history species.


Assuntos
Ecologia , Peixes/fisiologia , Animais , Clima , Mudança Climática , Ecossistema , Temperatura Alta , Dinâmica Populacional , Temperatura
8.
PLoS One ; 15(8): e0236660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785239

RESUMO

Squamate reptiles (snakes and lizards) rely on chemical cues from conspecifics to search the environment for potential mates. How such cues are used by invasive species to facilitate reproduction, especially seasonally, is a key question that can inform management practices. The Argentine black and white tegu (Salvator merianae) is an invasive reptile species in south Florida threatening native fauna in biodiverse regions such as Everglades National Park. While some information exists on the reproductive ecology of this species in its native range in South America, the chemical ecology of S. merianae is unclear especially in its invasive range. By testing both male (n = 7) and female (n = 7) tegus in a Y-maze apparatus, we assessed if either sex follows chemical trails left by conspecifics and if behaviors were sex- or season-specific. We conducted three types of trials where conspecifics created odor trails: Male-only (male scent only in base and one arm of Y), Female-only, and Male vs. female. Males did not preferentially follow scent trails from either sex, but they did differentially investigate conspecific scent from both sexes. Seasonally, males showed increased rates of chemosensory sampling (rates of tongue-flicking) during the spring (breeding season; March-May) compared to fall (non-breeding season; September-November). Males also had reduced turning and pausing behavior while trailing in the spring. Female tegus exhibited stronger conspecific trailing abilities than males, following both male and female scent trails, and they explored the maze less before making an arm choice. Females also investigated the scent trails intensely compared to males (more passes in scented arms, more time with scent trails). Our results demonstrate for the first time that females of an invasive reptile species can follow conspecific scent trails. Given the strong female responses to odor, sex-specific targeting of tegus via application of a conspecific chemical cue in traps could enhance removal rates of females during the breeding season.


Assuntos
Lagartos/fisiologia , Casamento , Comportamento Sexual Animal/fisiologia , Serpentes/fisiologia , Animais , Ecologia , Feminino , Florida , Humanos , Espécies Introduzidas , Masculino , Odorantes/análise , Reprodução/fisiologia , América do Sul
9.
Nat Commun ; 11(1): 3897, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753587

RESUMO

Lipo-chitooligosaccharides (LCOs) are signaling molecules produced by rhizobial bacteria that trigger the nodulation process in legumes, and by some fungi that also establish symbiotic relationships with plants, notably the arbuscular and ecto mycorrhizal fungi. Here, we show that many other fungi also produce LCOs. We tested 59 species representing most fungal phyla, and found that 53 species produce LCOs that can be detected by functional assays and/or by mass spectroscopy. LCO treatment affects spore germination, branching of hyphae, pseudohyphal growth, and transcription in non-symbiotic fungi from the Ascomycete and Basidiomycete phyla. Our findings suggest that LCO production is common among fungi, and LCOs may function as signals regulating fungal growth and development.


Assuntos
Quitina/análogos & derivados , Quitina/metabolismo , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Transdução de Sinais/fisiologia , Ascomicetos/crescimento & desenvolvimento , Basidiomycota/crescimento & desenvolvimento , Ecologia , Ácidos Graxos/metabolismo , Micorrizas/fisiologia , Rhizobium/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Simbiose/fisiologia
10.
Nat Commun ; 11(1): 3999, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778648

RESUMO

Land use change, by disrupting the co-evolved interactions between plants and their pollinators, could be causing plant reproduction to be limited by pollen supply. Using a phylogenetically controlled meta-analysis on over 2200 experimental studies and more than 1200 wild plants, we ask if land use intensification is causing plant reproduction to be pollen limited at global scales. Here we report that plants reliant on pollinators in urban settings are more pollen limited than similarly pollinator-reliant plants in other landscapes. Plants functionally specialized on bee pollinators are more pollen limited in natural than managed vegetation, but the reverse is true for plants pollinated exclusively by a non-bee functional group or those pollinated by multiple functional groups. Plants ecologically specialized on a single pollinator taxon were extremely pollen limited across land use types. These results suggest that while urbanization intensifies pollen limitation, ecologically and functionally specialized plants are at risk of pollen limitation across land use categories.


Assuntos
Ecologia , Fenômenos Fisiológicos Vegetais , Pólen , Polinização , Animais , Abelhas , Bases de Dados Factuais , Ecossistema , Filogenia , Plantas/classificação , Urbanização
11.
Nat Commun ; 11(1): 4353, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859908

RESUMO

Continental-scale models of malaria climate suitability typically couple well-established temperature-response models with basic estimates of vector habitat availability using rainfall as a proxy. Here we show that across continental Africa, the estimated geographic range of climatic suitability for malaria transmission is more sensitive to the precipitation threshold than the thermal response curve applied. To address this problem we use downscaled daily climate predictions from seven GCMs to run a continental-scale hydrological model for a process-based representation of mosquito breeding habitat availability. A more complex pattern of malaria suitability emerges as water is routed through drainage networks and river corridors serve as year-round transmission foci. The estimated hydro-climatically suitable area for stable malaria transmission is smaller than previous models suggest and shows only a very small increase in state-of-the-art future climate scenarios. However, bigger geographical shifts are observed than with most rainfall threshold models and the pattern of that shift is very different when using a hydrological model to estimate surface water availability for vector breeding.


Assuntos
Mudança Climática , Hidrologia/métodos , Malária/transmissão , África/epidemiologia , Animais , Anopheles/fisiologia , Ecologia , Ecossistema , Mapeamento Geográfico , Geografia , Malária/epidemiologia , Mosquitos Vetores/fisiologia , Rios , Estações do Ano , Temperatura
12.
PLoS One ; 15(8): e0237701, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817628

RESUMO

Mangroves are highly productive ecosystems that provide important environmental services, but have been impacted massively in recent years by human activities. Studies of mangroves have focused on their ecology and function at local or landscape scales, but little has been done to understand their broader distributional patterns or the environmental factors that determine those distributions. Species distribution models (SDMs), have been used to estimate potential distributions of hundreds of species, yet no SDM studies to date have assessed mangrove community distributions in Mexico (the country with the fourth largest extent of this ecosystem). We used maximum entropy approaches to model environmental suitability for mangrove species distributions in the country, and to identify the environmental factors most important in determining those distributions. We also evaluated whether this modeling approach is adequate to estimate mangrove distribution as a community across Mexico. Best models were selected based on statistical significance (AUC ratio), predictive performance (omission error of 5%), and model complexity (Akaike criterion); after this evaluation, only one model per species met the three evaluation criteria. Environmental variable sets that included distance to coast yielded significantly better models; variables with strongest contributions included elevation, temperature of the coldest month, and organic carbon content of soil. Based on our results, we conclude that SDMs can be used to map mangrove communities in Mexico, but that results can be improved at local scales with inclusion of local variables (salinity, hydroperiod and microtopography), field validations, and remote sensing data.


Assuntos
Conservação dos Recursos Naturais , Ecologia , Ecossistema , Áreas Alagadas , Atividades Humanas , Humanos , México , Modelos Teóricos , Solo
13.
PLoS One ; 15(8): e0237742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817669

RESUMO

Skipjack tuna (SJT) pelagic hotspots in the western North Pacific (WNP) were modelled using fishery and satellite remotely sensed data with Ecological Niche Factor Analysis (ENFA) models. Our objectives were to model and predict habitat hotspots for SJT and assess the monthly changes in sub-surface temperatures and mixed layer depths at fishing locations. SJT presence-only monthly resolved data, sea surface temperature, chlorophyll-a, diffuse attenuation coefficient, sea surface heights and surface wind speed were used to construct ENFA models and generate habitat suitability indices using a short-term dataset from March-November 2004. The suitability indices were then predicted for July-October (2007 and 2008). Monthly aggregated polygons of areas fished by skipjack tuna pole and line vessels were also overlaid on the predicted habitat suitability maps. Distributions of sub-surface temperatures and mixed layer depths (MLD) at fishing locations were also examined. Our results showed good fit for ENFA models, as indicated by the absolute validation index, the contrast validation index and the continuous Boyce index. The predicted hotspots showed varying concurrences when compared with 25-degree polygons derived from fished areas. Northward shifts in SJT hotspots corresponded with declining MLDs from March to September. The MLDs were shallower in summer and deeper in autumn and winter months. The habitat hotspots modeled using ENFA were consistent with the known ecology and seasonal migration pattern of SJT. The findings of this work, derived from a short-term dataset, enable identification of SJT hotspots in the WNP, thus contributing valuable information for future research on SJT habitat prediction models.


Assuntos
Ecologia , Pesqueiros , Tecnologia de Sensoriamento Remoto/métodos , Atum/fisiologia , Animais , Clorofila A/metabolismo , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Estações do Ano , Temperatura
14.
PLoS One ; 15(8): e0238243, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853270

RESUMO

In the North China Plain, coal mining subsided lakes are surface water bodies that form after the conclusion of coal mining. In China, mining subsided lakes are often transformed into artificial wetland parks for ecological restoration. While many studies have focused on evaluating coal mining subsidence lake ecosystem service value and water pollution, little attention has been paid to changes in ecological regimes and ecological spillover effects before and after the reclamation of mining areas. This paper examines the Pan'an Lake artificial wetland in Jiawang District, Xuzhou, as a case study. Changes in the ecological regime of the mining subsidence area before and after land reclamation and corresponding spatial spillover effect on land prices are assessed based on remote sensing, GIS raster calculations and geostatistical methods. The results show that the ecosystem service value and ecological storage capacity changed significantly after the mining subsided lake was transformed into an artificial wetland and the wetland ecosystem has been developing well with significantly positive spillover effects on surrounding land prices. From 2008 to 2017, service functions of the artificial wetland ecosystem of Pan'an Lake increased by 81.95%, and the system's ecological storage capacity increased from RMB 6,754 yuan/hm2 in 2008 to RMB 12,289 yuan/hm2 in 2017. The average impact of the Pan'an Lake artificial wetland on the spillover effects of surrounding residential land prices was measured at RMB 195.18 yuan/m2, and the total spillover value of planned residential land in the study area was measured at RMB 805,422,100 yuan. The present study can serve as a useful guide for evaluating the economic feasibility of land reclamation planning and ecological restoration in mining subsidence areas.


Assuntos
Minas de Carvão/métodos , Conservação dos Recursos Naturais/métodos , China , Ecologia/métodos , Ecossistema , Monitoramento Ambiental/métodos , Lagos , Áreas Alagadas
15.
Nature ; 584(7821): 346-347, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760034
16.
PLoS One ; 15(7): e0236895, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735578

RESUMO

Many studies on the coexistence of wildlife with livestock have focused primarily on similar-sized species. Furthermore, many of these studies have used dietary overlap as a measure of potential competition between interacting species and thus lack the important link between dietary overlap and any negative effects on a particular species-a prerequisite for competition. Consequently, the mechanisms that drive interspecific interactions between wildlife and cattle are frequently overlooked. To address this, we used an experimental setup where we leveraged different cattle stocking rates across two seasons to identify the drivers of interspecific interactions (i.e. competition and facilitation) between smaller-bodied oribi antelope and cattle. Using direct foraging observations, we assessed dietary overlap and grass regrowth, and also calculated oribi nutritional intake rates. Ultimately, we found that cattle compete with, and facilitate, smaller-bodied oribi antelope through bottom-up control. Specifically, cattle facilitated oribi during the wet season, irrespective of cattle stocking density, because cattle foraging produced high-quality grass regrowth. In contrast, during the dry season, cattle and oribi did not co-exist in the same areas (i.e. no direct dietary overlap). Despite this, we found that cattle foraging at high densities during the previous wet season reduced the dry season availability of oribi's preferred grass species. To compensate, oribi expanded their dry season diet breadth and included less palatable grass species, ultimately reducing their nutritional intake rates. Thus, cattle competed with oribi through a delayed, across-season habitat modification. We show that differences in body size alone may not be able to offset competitive interactions between cattle and wildlife. Finally, understanding the mechanisms that drive facilitation and competition are key to promoting co-existence between cattle and wildlife.


Assuntos
Antílopes/fisiologia , Comportamento Alimentar , Gado/fisiologia , Animais , Animais Selvagens/fisiologia , Tamanho Corporal , Bovinos , Conservação dos Recursos Naturais , Dieta/veterinária , Ecologia , Ecossistema , Herbivoria/fisiologia , Poaceae , Estações do Ano , África do Sul
17.
PLoS One ; 15(8): e0236978, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797083

RESUMO

Advancements in statistical ecology offer the opportunity to gain further inferences from existing data with minimal financial cost. Spatial capture-recapture (SCR) models extend traditional capture-recapture models to incorporate spatial position of capture and enable direct estimation of animal densities across a region of interest. The additional inferences provided are both ecologically interesting and valuable for decision making, which has resulted in traditional capture-recapture data being repurposed using SCR. Yet, many capture-recapture studies were not designed for SCR and the limitations of repurposing data from such studies are rarely assessed in practice. We used simulation to evaluate the robustness of SCR for retrospectively estimating large mammal densities over a variety of scenarios using repurposed capture-recapture data collected by an asymmetrical sampling grid and covering a broad spatial extent in a heterogenous landscape. We found performance of SCR models fit using repurposed data simulated from the existing grid was not robust, but instead bias and precision of density estimates varied considerably among simulations scenarios. For example, while the smallest relatives bias of density estimates was 3%, it ranged by 14 orders of magnitude among scenarios and was most strongly influenced by detection parameters. Our results caution against the casual repurposing of non-spatial capture-recapture data using SCR and demonstrate the importance of using simulation to assessing model performance during retrospective applications.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Modelos Animais , Modelos Biológicos , Animais , Simulação por Computador , Coleta de Dados , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Ecologia/métodos , Ecologia/estatística & dados numéricos , Ecossistema , Michigan , Densidade Demográfica , Ursidae
18.
OMICS ; 24(8): 479-482, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32644877

RESUMO

In times of planetary health crises such as the COVID-19 pandemic, a critically informed science and technology policy is crucial. In this overarching context, governments are faced with making rapid and high-stake decisions dictated by emergency that in a state of normalcy they would not, or could not pursue. Governments tend to gather, therefore, an incredible amount of unchecked power in times of fast-moving ecological crises that raises concerns about where the legitimacy of such excessive power comes from. Moreover, the elected politicians rely on the expert advice in a pandemic. This takes away democratic political authority from the sovereign people and instead places it on allegedly objective unelected experts. In contrast, experts have (1) a dubious reputation in predicting the future and (2) varying degrees of biases and self-interests, which make them susceptible, for instance, to "framing problems" in relation to the urgent public issues at stake. This article suggests new ways of thinking about COVID-19 technology policy, drawing from the field of political science and democratic theory. It examines the power-laden tensions between the political authority and the expert authority. Going forward, I highlight the brief history of epistemic democracy, taking into consideration that in advanced modern democracies, political decision making has to draw, in part, from expert knowledge, but without resulting in democratic deficits. The COVID-19 science and technology policy can usefully build on epistemic democracy while strengthening the science, society, and democracy nexus.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Saúde Pública/legislação & jurisprudência , Ciência/legislação & jurisprudência , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Democracia , Ecologia , Humanos , Conhecimento , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia
19.
Proc Biol Sci ; 287(1930): 20200649, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32605514

RESUMO

Predicting how communities re-arrange in response to changes in species composition remains a key challenge in ecology. Migratory species, which enter and leave communities across latitudinal gradients, offer us a unique opportunity to evaluate community- and species-level responses to a shift in community composition. We focused on a migratory hummingbird and the communities that host it along a latitudinal and species diversity gradient. Our results show higher niche overlap in more diverse communities, allowing resident species to compensate for the loss of the migrant in providing pollination services. Contrastingly, in less diverse communities, the migrant behaves as a specialist, monopolizing abundant resources. In its absence, its role is not fully covered by resident species, resulting in a decrease in the fruit set of the migrant's preferred plant species. These results help us understand the potential impacts of biodiversity loss and have important implications for community persistence given expected changes in the migratory behaviours of some species.


Assuntos
Migração Animal , Polinização , Animais , Biodiversidade , Aves , Ecologia , Ecossistema , Flores , Frutas , Plantas
20.
Proc Biol Sci ; 287(1930): 20200248, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32635874

RESUMO

Environmental DNA (eDNA) has the potential to provide more comprehensive biodiversity assessments, particularly for vertebrates in species-rich regions. However, this method requires the completeness of a reference database (i.e. a list of DNA sequences attached to each species), which is not currently achieved for many taxa and ecosystems. As an alternative, a range of operational taxonomic units (OTUs) can be extracted from eDNA metabarcoding. However, the extent to which the diversity of OTUs provided by a limited eDNA sampling effort can predict regional species diversity is unknown. Here, by modelling OTU accumulation curves of eDNA seawater samples across the Coral Triangle, we obtained an asymptote reaching 1531 fish OTUs, while 1611 fish species are recorded in the region. We also accurately predict (R² = 0.92) the distribution of species richness among fish families from OTU-based asymptotes. Thus, the multi-model framework of OTU accumulation curves extends the use of eDNA metabarcoding in ecology, biogeography and conservation.


Assuntos
Biodiversidade , DNA Ambiental , Monitoramento Ambiental , Peixes , Animais , Antozoários , Código de Barras de DNA Taxonômico , Ecologia , Ecossistema , Água do Mar
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