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1.
Sci Total Environ ; 804: 150053, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34520914

RESUMO

The extensive exploitation and use of land resources has caused a variety of land degradation problems including soil erosion, desertification and salinization in China, which gradually raises our concerns of ecological security. However, there still lacks an understanding of ecological security of land resources at the national scale. Moreover, few studies conduct the validation and uncertainty analysis of models for ecological security evaluation, which tends to undermine the reliability of evaluation results. Here we followed the Pressure-State-Response (PSR) framework to systematically construct the evaluation index system for ecological security, and developed fuzzy evaluation models to convert the original index data into individual index scores. After that, we used the multiplicative model to aggregate the individual index scores into a comprehensive evaluation score for the ecological security level of land resources across the Chinese mainland. To enhance the reliability of evaluation results, we validated our results by comparing with the proxies of ecological effects including landscape pattern index, land use change rate and net primary productivity, and made uncertainty analysis using the Monte Carlo method. Finally, we applied an obstacle model to quantify the negative contribution of pressure, state and response which would deter the security from achieving the optimal condition. The results showed that our model could effectively reflect the ecological security level of land resources. The pressure was higher in the east and lower in the west of China, and that of urban areas was much higher than the rural areas, reflecting the disturbance of socio-economic activities. The state condition was strongly related to natural conditions. The response level, determined mainly by socio-economic conditions, was higher in the southeast and northwest of China but lower in the northeast and southwest of China. The ecological security level was structured by natural and socio-economic conditions and demonstrated a high level of security in the southeast while a low level in the northwest. Developed urban areas often had low security due to strong socio-economic pressure. Areas with unfavorable natural and environmental conditions had poor state level, which tended to cause lower response capability, and consequently led to a low security level. Our research improves the understanding of national ecological security and its obstacle factors, which supports the management and sustainable use of land resources at the national scale.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Ecologia , Reprodutibilidade dos Testes
2.
Environ Monit Assess ; 193(12): 771, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34738174

RESUMO

Global climate change will cause significant changes in climate parameters, especially temperature increases and changes in precipitation regimes worldwide. Since the life of living things is directly related to climate parameters, this process will inevitably affect all living things. The plants will be the most affected living things from this process because they do not have an effective movement and migration mechanism. Therefore, global climate change will cause significant species and population losses in plants. To minimize the potential loss of species and populations, it is necessary to predetermine the potential changes in species' distribution areas and take necessary actions. Therefore, this study was aimed to determine the distribution areas of three Tilia species (Tilia tomentosa, Tilia cordata, and Tilia platyphyllos), which have economic, ecologic, and social value and show the local distribution in Turkey and to determine how they will be affected by global climate change. Within this scope, nineteen bioclimatic variables, Emberger climate classification, aspect, and topographic altitude variable were used in the modeling process. By modeling the scenarios SSP 245 and SSP 585, the projections were made for 2040, 2060, 2080, and 2100 regarding the areas suitable for the growth of these species and how these areas will change compared to their current situation. The results suggest that the distribution areas of all three Tilia species will change due to climate change, and the area of loss will be 43.5 km2 (4%) for T. tomentosa, 9953.6 km2 (15%) for T. platyphyllos, and 448.0 km2 (19%) for T. cordata. Moreover, a more important point here is that increases and decreases will be observed in their distribution areas, and these changes will occur in a short process and at significant levels. In this case, the migration mechanism that these species will require must be provided by humans.


Assuntos
Mudança Climática , Tilia , Ecologia , Monitoramento Ambiental , Humanos , Turquia
4.
J R Soc Interface ; 18(183): 20210486, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34665977

RESUMO

The relationship between network structure and dynamics is one of the most extensively investigated problems in the theory of complex systems of recent years. Understanding this relationship is of relevance to a range of disciplines-from neuroscience to geomorphology. A major strategy of investigating this relationship is the quantitative comparison of a representation of network architecture (structural connectivity, SC) with a (network) representation of the dynamics (functional connectivity, FC). Here, we show that one can distinguish two classes of functional connectivity-one based on simultaneous activity (co-activity) of nodes, the other based on sequential activity of nodes. We delineate these two classes in different categories of dynamical processes-excitations, regular and chaotic oscillators-and provide examples for SC/FC correlations of both classes in each of these models. We expand the theoretical view of the SC/FC relationships, with conceptual instances of the SC and the two classes of FC for various application scenarios in geomorphology, ecology, systems biology, neuroscience and socio-ecological systems. Seeing the organisation of dynamical processes in a network either as governed by co-activity or by sequential activity allows us to bring some order in the myriad of observations relating structure and function of complex networks.


Assuntos
Ecologia , Ecossistema , Encéfalo
5.
Prog Chem Org Nat Prod ; 116: 37-66, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34698945

RESUMO

The interdisciplinary field of Chemical Ecology in Brazil is currently composed of groups that emerged through the pioneering studies of Keith Spalding Brown Jr. and José Tércio Barbosa Ferreira. Following Keith Brown 's steps, José Roberto Trigo continued investigating the role of plant natural products in mediating the association among insects and their host plants, mainly in the Order Lepidoptera. The role of pyrrolizidine alkaloids in those associations was investigated extensively by Brown and Trigo, and most of what is currently known on this subject is based on their studies. The present work acknowledges their contribution to the Brazilian chemical ecology field and on insect-plant communication studies mediated by different chemical compounds.


Assuntos
Lepidópteros , Alcaloides de Pirrolizidina , Animais , Brasil , Ecologia , Plantas
6.
New Phytol ; 232(3): 973-1122, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34608637

RESUMO

In the context of a recent massive increase in research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on generating cutting-edge, meaningful and integrated knowledge. Consideration of the below-ground components in plant and ecosystem studies has been consistently called for in recent decades, but methodology is disparate and sometimes inappropriate. This handbook, based on the collective effort of a large team of experts, will improve trait comparisons across studies and integration of information across databases by providing standardised methods and controlled vocabularies. It is meant to be used not only as starting point by students and scientists who desire working on below-ground ecosystems, but also by experts for consolidating and broadening their views on multiple aspects of root ecology. Beyond the classical compilation of measurement protocols, we have synthesised recommendations from the literature to provide key background knowledge useful for: (1) defining below-ground plant entities and giving keys for their meaningful dissection, classification and naming beyond the classical fine-root vs coarse-root approach; (2) considering the specificity of root research to produce sound laboratory and field data; (3) describing typical, but overlooked steps for studying roots (e.g. root handling, cleaning and storage); and (4) gathering metadata necessary for the interpretation of results and their reuse. Most importantly, all root traits have been introduced with some degree of ecological context that will be a foundation for understanding their ecological meaning, their typical use and uncertainties, and some methodological and conceptual perspectives for future research. Considering all of this, we urge readers not to solely extract protocol recommendations for trait measurements from this work, but to take a moment to read and reflect on the extensive information contained in this broader guide to root ecology, including sections I-VII and the many introductions to each section and root trait description. Finally, it is critical to understand that a major aim of this guide is to help break down barriers between the many subdisciplines of root ecology and ecophysiology, broaden researchers' views on the multiple aspects of root study and create favourable conditions for the inception of comprehensive experiments on the role of roots in plant and ecosystem functioning.


Assuntos
Ecossistema , Plantas , Bases de Dados Factuais , Ecologia , Fenótipo
7.
J Hist Behav Sci ; 57(4): 336-357, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34599515

RESUMO

This essay traces how the concept of energy-defined as the ability to do work in physics-informed two similar fields of knowledge with very dissimilar results. One, the resource economy in the late 19th century, laid some important epistemic and ideological foundations for the destruction of the environment in the present. The other, ecology, introduced a new holistic view of nature, which laid the groundwork for the recent reconceptualization of ethics, epistemology, and humankind's role on Earth culminating in the Anthropocene hypothesis-formulated in direct opposition to the capitalist, anthropocentric notions inherited from the 19th century. In both cases, it was the concept of energy that enabled thinking about the multifarious visualities, materialities, and temporalities of natural phenomena as united in a single causal substructure of energy exchanges. In resource economics, the energetic worldview imposed an anthropocentric useful/useless divide on the environment-modeled, I argue, on the energy/entropy distinction-and made it "logical" to think of minerals, plants, and human labor as analogous resources, justifiably equated and linked in the economic system. The same ability to equate and connect was fundamental to the discipline of ecology and its application to sociology in the 20th century, and, in more recent years, to philosophy and historiography. In stripping nature of all surface illusions, energy proved enormously efficient for exposing the entanglement of large-scale systems composed of animate and inanimate actors equally imbued with agency.


Assuntos
Ecologia , Filosofia , Capitalismo , História do Século XX , Humanos , Conhecimento , Plantas
8.
Oecologia ; 197(3): 661-674, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34657196

RESUMO

Droughts can affect invertebrate communities in wetlands, which can have bottom-up effects on the condition and survival of top predators. Shorebirds, key predators at coastal wetlands, have experienced widespread population declines and could be negatively affected by droughts. We explored, in detail, the effects of drought on multiple aspects of shorebird stopover and migration ecology by contrasting a year with average wet/dry conditions (2016) with a year with moderate drought (2017) at a major subarctic stopover site on southbound migration. We also examined the effects of drought on shorebird body mass during stopover across 14 years (historical: 1974-1982 and present-day: 2014-2018). For the detailed comparison of two years, in the year with moderate drought we documented lower invertebrate abundance at some sites, higher prey family richness in shorebird faecal samples, lower shorebird refuelling rates, shorter stopover durations for juveniles, and, for most species, a higher probability of making a subsequent stopover in North America after departing the subarctic, compared to the year with average wet/dry conditions. In the 14-year dataset, shorebird body mass tended to be lower in drier years. We show that even short-term, moderate drought conditions can negatively affect shorebird refuelling performance at coastal wetlands, which may carry-over to affect subsequent stopover decisions. Given shorebird population declines and predicted changes in the severity and duration of droughts with climate change, researchers should prioritize a better understanding of how droughts affect shorebird refuelling performance and survival.


Assuntos
Migração Animal , Áreas Alagadas , Animais , Secas , Ecologia , Invertebrados
9.
Nat Commun ; 12(1): 6017, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650048

RESUMO

Circadian rhythms in gut microbiota composition are crucial for metabolic function, yet the extent to which they govern microbial dynamics compared to seasonal and lifetime processes remains unknown. Here, we investigate gut bacterial dynamics in wild meerkats (Suricata suricatta) over a 20-year period to compare diurnal, seasonal, and lifetime processes in concert, applying ratios of absolute abundance. We found that diurnal oscillations in bacterial load and composition eclipsed seasonal and lifetime dynamics. Diurnal oscillations were characterised by a peak in Clostridium abundance at dawn, were associated with temperature-constrained foraging schedules, and did not decay with age. Some genera exhibited seasonal fluctuations, whilst others developed with age, although we found little support for microbial senescence in very old meerkats. Strong microbial circadian rhythms in this species may reflect the extreme daily temperature fluctuations typical of arid-zone climates. Our findings demonstrate that accounting for circadian rhythms is essential for future gut microbiome research.


Assuntos
Carga Bacteriana , Ritmo Circadiano , Microbioma Gastrointestinal , Estações do Ano , Animais , Bactérias/genética , Biodiversidade , Clostridium , Biologia Computacional , DNA Bacteriano , Ecologia , Microbioma Gastrointestinal/genética , Humanos , Projetos Piloto , RNA Ribossômico 16S/genética
10.
Ecol Lett ; 24(12): 2796-2811, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34608730

RESUMO

Microbiomes have profound effects on host fitness, yet we struggle to understand the implications for host ecology. Microbiome influence on host ecology has been investigated using two independent frameworks. Classical ecological theory powerfully represents mechanistic interactions predicting environmental dependence of microbiome effects on host ecology, but these models are notoriously difficult to evaluate empirically. Alternatively, host-microbiome feedback theory represents impacts of microbiome dynamics on host fitness as simple net effects that are easily amenable to experimental evaluation. The feedback framework enabled rapid progress in understanding microbiomes' impacts on plant ecology, and can also be applied to animal hosts. We conceptually integrate these two frameworks by deriving expressions for net feedback in terms of mechanistic model parameters. This generates a precise mapping between net feedback theory and classic population modelling, thereby merging mechanistic understanding with experimental tractability, a necessary step for building a predictive understanding of microbiome influence on host ecology.


Assuntos
Microbiota , Animais , Ecologia , Retroalimentação
11.
Biol Lett ; 17(10): 20210363, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34610253

RESUMO

Rapid species turnover in tropical mountains has fascinated biologists for centuries. A popular explanation for this heightened beta diversity is that climatic stability at low latitudes promotes the evolution of narrow thermal tolerance ranges, leading to local adaptation, evolutionary divergence and parapatric speciation along elevational gradients. However, an emerging consensus from research spanning phylogenetics, biogeography and behavioural ecology is that this process rarely, if ever, occurs. Instead, closely related species typically occupy a similar elevational niche, while species with divergent elevational niches tend to be more distantly related. These results suggest populations have responded to past environmental change not by adapting and diverging in place, but instead by shifting their distributions to tightly track climate over time. We argue that tropical species are likely to respond similarly to ongoing and future climate warming, an inference supported by evidence from recent range shifts. In the absence of widespread in situ adaptation to new climate regimes by tropical taxa, conservation planning should prioritize protecting large swaths of habitat to facilitate movement.


Assuntos
Mudança Climática , Especiação Genética , Ecologia , Ecossistema , Filogenia
12.
PLoS One ; 16(10): e0255321, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34634069

RESUMO

BACKGROUND: An. funestus is a major Afrotropical vector of human malaria. This study sought to investigate the larval ecology, sporozoite infection rates and blood meal sources of An. funestus in western Kenya. METHODS: Larval surveys were carried out in Bungoma (Highland) and Kombewa (lowland) of western Kenya. Aquatic habitats were identified, characterized, georeferenced and carefully examined for mosquito larvae and predators. Indoor resting mosquitoes were sampled using pyrethrum spray catches. Adults and larvae were morphologically and molecularly identified to species. Sporozoite infections and blood meal sources were detected using real-time PCR and ELISA respectively. RESULTS: Of the 151 aquatic habitats assessed, 62/80 (78%) in Bungoma and 58/71(82%) in Kombewa were positive for mosquito larvae. Of the 3,193 larvae sampled, An. funestus larvae constitute 38% (1224/3193). Bungoma recorded a higher number of An. funestus larvae (85%, 95%, CI, 8.722-17.15) than Kombewa (15%, 95%, CI, 1.33-3.91). Molecular identification of larvae showed that 89% (n = 80) were An. funestus. Approximately 59%, 35% and 5% of An. funestus larvae co-existed with An. gambiae s.l, Culex spp and An. coustani in the same habitats respectively. Of 1,221 An. funestus s.l adults sampled, molecular identifications revealed that An. funestus constituted 87% (n = 201) and 88% (n = 179) in Bungoma and Kombewa, respectively. The Plasmodium falciparum sporozoite rate of An. funestus in Bungoma and Kombewa was 2% (3/174) and 1% (2/157), respectively, and the human blood index of An. funestus was 84% (48/57) and 89% (39/44) and for Bungoma and Kombewa, respectively. CONCLUSION: Man-made ponds had the highest abundance of An. funestus larvae. Multiple regression and principal component analyses identified the distance to the nearest house as the key environmental factor associated with the abundance of An. funestus larvae in aquatic habitats. This study serves as a guide for the control of An. funestus and other mosquito species to complement existing vector control strategies.


Assuntos
Anopheles/embriologia , Larva/crescimento & desenvolvimento , Malária Falciparum/transmissão , Controle de Mosquitos/métodos , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/parasitologia , Animais , Anopheles/parasitologia , Ecologia , Humanos , Mosquiteiros Tratados com Inseticida , Inseticidas/farmacologia , Quênia , Larva/parasitologia , Plasmodium falciparum/isolamento & purificação
13.
Nature ; 597(7876): 360-365, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34526707

RESUMO

Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.


Assuntos
Aquicultura , Ecossistema , Monitoramento Ambiental , Alimentos Marinhos , Desenvolvimento Sustentável , Animais , Aquicultura/tendências , Mudança Climática , Dieta , Ecologia , Política Ambiental , Pesqueiros , Abastecimento de Alimentos/métodos , Gases de Efeito Estufa , Humanos , Moluscos , Nitrogênio , Fósforo , Alimentos Marinhos/provisão & distribuição , Alga Marinha , Desenvolvimento Sustentável/tendências
14.
Nat Ecol Evol ; 5(9): 1187, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34475554

Assuntos
Ecologia
15.
Ecol Lett ; 24(11): 2490-2505, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34482609

RESUMO

For decades, people have reduced the transmission of pathogens by adding low-quality hosts to managed environments like agricultural fields. More recently, there has been interest in whether similar 'dilution effects' occur in natural disease systems, and whether these effects are eroded as diversity declines. For some pathogens of plants, humans and other animals, the highest-quality hosts persist when diversity is lost, so that high-quality hosts dominate low-diversity communities, resulting in greater pathogen transmission. Meta-analyses reveal that these natural dilution effects are common. However, studying them remains challenging due to limitations on the ability of researchers to manipulate many disease systems experimentally, difficulties of acquiring data on host quality and confusion about what should and should not be considered a dilution effect. Because dilution effects are widely used in managed disease systems and have been documented in a variety of natural disease systems, their existence should not be considered controversial. Important questions remain about how frequently they occur and under what conditions to expect them. There is also ongoing confusion about their relationships to both pathogen spillover and general biogeographical correlations between diversity and disease, which has resulted in an inconsistent and confusing literature. Progress will require rigorous and creative research.


Assuntos
Biodiversidade , Ecologia , Animais , Humanos , Plantas
16.
Oecologia ; 197(2): 459-469, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34476548

RESUMO

Phylogenetic ecology uses evolutionary history to improve understanding of plant interactions. Phylogenetic distance can mediate plant interactions such as competition (e.g., via limiting similarity) and facilitation (e.g., via niche complementarity), influencing community assembly patterns. Previous research has found evidence both for and against a relationship between phylogenetic distance and the strength of plant interactions, and has found that other factors, such as trait differences, may be more influential. In addition to phylogenetic distance and species' traits, environmental conditions can also influence competition, with facilitative interactions-particularly among distantly related species-potentially becoming more pronounced under stressful, resource-limited conditions. We tested the prediction that greater phylogenetic distance is associated with decreased competition in a greenhouse experiment using plant species of the North American tallgrass prairie. We calculated the Relative Interaction Index for 81 species pairs using plant height, leaf length, and biomass as indicators of performance. We found that phylogenetic distance alone did not significantly affect competition. However, the interaction between phylogenetic distance and stressful conditions (sandier soils with low nutrient availability and water retention vs. resource-rich potting soil) altered plant traits and competition. Under stressful conditions, more distantly related species competed more strongly, leading to smaller plants. Conversely, under benign conditions more distantly related species pairs competed less and were larger. These results were contrary to our expectations that distant relatives would compete less under stressful conditions. Our experiment provides evidence that, while relatedness alone may not drive competition, phylogenetic distance can nonetheless be influential through interactions with environmental conditions.


Assuntos
Ecologia , Ecossistema , Evolução Biológica , Filogenia , Plantas
17.
Oecologia ; 197(2): 421-436, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34524544

RESUMO

The parallel evolution of similar ecotypes in response to comparable environmental conditions is believed to reveal the importance of divergent selection in phenotypic diversifying processes. Systems characterized by the presence of multiple replicate populations expressing resource polymorphism thus provide an ideal opportunity to address the occurrence and factors affecting the parallel evolution of ecotypes. Previous studies have shown that brook charr (Salvelinus fontinalis) exhibit resource polymorphism in some Canadian Shield lakes, where a littoral ecotype feeds mainly on zoobenthos and a pelagic ecotype feeds mostly on zooplankton. Using morphological traits and geometric morphometric analyses on 18 native brook charr populations, we explicitly tested (i) whether brook charr ecotypes show parallel evolution across populations (i.e. the same morphological traits discriminate ecotypes among lakes) and (ii) whether interspecific competition decreases the amplitude of morphological differentiation between ecotypes, if any, because brook charr experience some level of competitive exclusion from the littoral habitat in the presence of creek chub or white sucker. We observed a low level of parallel evolution, where the littoral ecotype was overall stouter with longer fins and smaller eyes than the pelagic ecotype. Interspecific competition had no clear impacts on the amplitude of morphological differentiation. We also observed that inter-lake morphological differences are greater than between ecotypes within lakes, suggesting an important effect of local environmental factors on population morphology. Early-stage of diversification as well as phenotypic plasticity and morphological integration could explain why resource polymorphism is still subtle in brook charr populations.


Assuntos
Somatotipos , Truta , Animais , Canadá , Ecologia , Fenótipo , Truta/genética
18.
Oecologia ; 197(2): 353-364, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34546495

RESUMO

Beta-diversity was originally defined spatially, i.e., as variation in community composition among sites in a region. However, the concept of beta-diversity has since been expanded to temporal contexts. This is referred to as "temporal beta-diversity", and most approaches are simply an extension of spatial beta-diversity. The persistence and turnover of individuals over time is a unique feature of temporal beta-diversity. Nakadai (2020) introduced the "individual-based beta-diversity" concept, and provided novel indices to evaluate individual turnover and compositional shift by comparing individual turnover between two periods at a given site. However, the proposed individual-based indices are applicable only to pairwise dissimilarity, not to multiple-temporal (or more generally, multiple-unit) dissimilarity. Here, individual-based beta-diversity indices are extended to multiple-unit cases. In addition, a novel type of random permutation criterion related to these multiple-unit indices for detecting patterns of individual persistence is introduced in the present study. To demonstrate the usage the properties of these indices compared to average pairwise measures, I applied them to a dataset for a permanent 50-ha forest dynamics plot on Barro Colorado Island in Panama. Information regarding "individuals" is generally missing from community ecology and biodiversity studies of temporal dynamics. In this context, the methods proposed here are expected to be useful for addressing a wide range of research questions regarding temporal changes in biodiversity, especially studies using traditional individual-tracked forest monitoring data.


Assuntos
Biodiversidade , Florestas , Colorado , Ecologia , Humanos , Panamá
19.
Mol Ecol ; 30(20): 5009-5028, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34490661

RESUMO

Dispersal is a central process in ecology and evolution with far reaching consequences for the dynamics and genetics of spatially structured populations (SSPs). Individuals can adjust their decisions to disperse according to local fitness prospects, resulting in context-dependent dispersal. By determining dispersal rate, distance and direction, these individual-level decisions further modulate the demography, relatedness and genetic structure of SSPs. Here, we examined how context-dependent dispersal influences the dynamics and genetics of a great crested newt (Triturus cristatus) SSP. We collected capture-recapture data of 5564 individuals and genetic data of 950 individuals across an SSP in northern Germany. We added genetic data from six sites outside this SSP to assess genetic structure and gene flow at a regional level. Dispersal rates within the SSP were high but dispersal distances were short. Dispersal was context-dependent: individuals preferentially immigrated into high-quality ponds where breeding probabilities were higher. The studied SSP behaved like a patchy population, where subpopulations at each pond were demographically interdependent. High context-dependent dispersal led to weak but significant spatial genetic structure and relatedness within the SSP. At the regional level, a strong hierarchical genetic structure with very few first-generation migrants as well as low effective dispersal rates suggest the presence of independent demographic units. Overall, our study highlights the importance of habitat quality for driving context-dependent dispersal and therefore demography and genetic structure in SSPs. Limited capacity for long-distance dispersal seems to increase genetic structure within a population and leads to demographic isolation in anthropogenic landscapes.


Assuntos
Anfíbios , Ecologia , Animais , Ecossistema , Humanos , Repetições de Microssatélites/genética , Densidade Demográfica , Dinâmica Populacional
20.
Annu Rev Biomed Data Sci ; 4: 369-391, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34465172

RESUMO

Viruses are the most abundant biological entity on Earth, infect cellular organisms from all domains of life, and are central players in the global biosphere. Over the last century, the discovery and characterization of viruses have progressed steadily alongside much of modern biology. In terms of outright numbers of novel viruses discovered, however, the last few years have been by far the most transformative for the field. Advances in methods for identifying viral sequences in genomic and metagenomic datasets, coupled to the exponential growth of environmental sequencing, have greatly expanded the catalog of known viruses and fueled the tremendous growth of viral sequence databases. Development and implementation of new standards, along with careful study of the newly discovered viruses, have transformed and will continue to transform our understanding of microbial evolution, ecology, and biogeochemical cycles, leading to new biotechnological innovations across many diverse fields, including environmental, agricultural, and biomedical sciences.


Assuntos
Metagenômica , Vírus , Ecologia , Genoma Viral , Metagenoma , Vírus/genética
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