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1.
Knowledge about the phylogenetic history, genetic variation and ecological requirements of a species is important for its conservation and management. Unfortunately, for many species this information is lacking. Here we use multiple approaches (phylogenetics, population genetics and ecological modelling) to evaluate the evolutionary history and conservation status of Capra walie , an endangered flagship species of wild goat endemic to Ethiopia. The analysis of mitochondrial cytochrome b and Y-chromosome DNA sequences suggests that C. walie forms a monophyletic clade with Capra nubiana , but potentially has been isolated for up to 0.8 million years from this closely related species. Microsatellite DNA analyses show that C. walie has very low genetic variation (mean heterozygosity=0.35) compared with other endangered mammals. This reduced variation likely derives from a prolonged demographic decline and small effective population size. Ecological niche modelling using the bioclimatic features of habitats occupied by C. walie , suggests ecological differences between C. walie and C. nubiana , and identifies the areas most suitable for future reintroductions of C. walie . The genetic and bioclimatic data suggest that C. walie is distinct and requires immediate conservation actions including genetic monitoring and reintroductions to establish independent populations. This study illustrates how combining noninvasive sampling along with genetic and ecological (bioclimatic) approaches can help assess conservation status of poorly known species.  相似文献   

2.
宾淑英  吴仲真  张鹤  林进添 《昆虫学报》2014,57(9):1094-1104
遗传变异与种群持续性及其进化潜力密切相关,而生物入侵导致种群遗传变异或遗传多样性的改变为研究自然界中各种生态和进化问题提供了理想模式。分子标记技术是调查种群遗传变异的重要工具,揭示了入侵种的入侵过程和结果,并预测未来的发生情况。本综述归纳了分子标记技术在昆虫入侵机制研究中的应用,以典型的研究个案为例,分别综述了分子标记技术在隐蔽入侵的监测应用,分子标记技术在重构入侵历史研究中的推算方式,分子标记技术在探索种群遗传变异与成功入侵机制方面取得的重要进展,并进一步介绍了高分辨率熔解曲线(high-resolution melting, HRM)分析在昆虫入侵研究中的应用前景。  相似文献   

3.
The power of molecular genetic techniques to address ecological research questions has opened a distinct interdisciplinary research area collectively referred to as molecular ecology. Molecular ecology combines aspects of diverse research fields like population and evolutionary genetics, as well as biodiversity, conservation biology, behavioural ecology, or species-habitat interactions. Molecular techniques detect specific DNA sequence characteristics that are used as genetic markers to discriminate individuals or taxonomic groups, for instance in analyses of population and community structures, for elucidation of phylogenetic relationships, or for the characterization and monitoring of specific strains in the environment. Here, we summarize the PCR-based molecular techniques used in molecular ecological research on fungal entomopathogens and discuss novel techniques that may have relevance to the studies of entomopathogenic fungi in the future. We discuss the flow chart of the molecular ecology approaches and we highlight some of the critical steps involved. There are still many unresolved questions in the understanding of the ecology of fungal entomopathogens. These include population characteristics and relations of genotypes and habitats as well as host-pathogen interactions. Molecular tools can provide substantial support for ecological research and offer insight into this far inaccessible systems. Application of molecular ecology approaches will stimulate and accelerate new research in the field of entomophathogen ecology.  相似文献   

4.
Recent improvements in genetic analysis and genotyping methods have resulted in a rapid expansion of the power of molecular markers to address ecological questions. Microsatellites have emerged as the most popular and versatile marker type for ecological applications. The rise of commercial services that can isolate microsatellites for new study species and genotype samples at reasonable prices presents ecologists with the unprecedented ability to employ genetic approaches without heavy investment in specialized equipment. Nevertheless, the lack of accessible, synthesized information on the practicalities and pitfalls of using genetic tools impedes ecologists' ability to make informed decisions on using molecular approaches and creates the risk that some will use microsatellites without understanding the steps needed to evaluate the quality of a genetic data set. The first goal of this synthesis is to provide an overview of the strengths and limitations of microsatellite markers and the risks, cost and time requirements of isolating and using microsatellites with the aid of commercial services. The second goal is to encourage the use and consistent reporting of thorough marker screening to ensure high quality data. To that end, we present a multistep screening process to evaluate candidate loci for inclusion in a genetic study that is broadly targeted to both novice and experienced geneticists alike.  相似文献   

5.
Microcystis aeruginosa is a well-known Cyanobacterium responsible for the formation of toxic water blooms around the world. Shallow, warm, and eutrophic reservoirs provide the most favourable conditions for M. aeruginosa development. Numerous studies have been devoted to this species, but there still is a necessity to develop additional approaches for the monitoring of cyanobacteria in reservoirs. In this study, M. aeruginosa in the water column of a hypereutrophic Siberian reservoir was investigated by fluorescence, light, and electron microscopy as well as genetic analysis using a mcyE marker. Here, we demonstrate the genetic diversity and features of the fluorescence spectra for different ecotypes of this species. We suggest that a fluorescence approach can be used to identify M. aeruginosa in a natural environment in order to increase the effectiveness of ecological monitoring and water quality evaluation.  相似文献   

6.
Current isolation methods access only a small subset of the total microbial diversity. Although an isolate traditionally has been required for genomic characterization, the advent of sequencing of entire natural microbial communities enables culture-independent genomic analysis. Information about the genetic potential of uncultivated organisms can be used to predict the form of metabolic interdependencies and nutritional requirements. We believe that this could provide the information necessary to bypass bottlenecks that have inhibited cultivation of many microorganisms. However, it might not be practical or possible to isolate all of the vast number of microbial species and strains for laboratory-based characterization. Ultimately, cultivation-independent genomic and genomically enabled approaches could provide a way to directly analyze microbial activity in its geochemical and ecological context.  相似文献   

7.
Recent ecological studies have revealed that rapid evolution within populations can have significant impacts on the ecological dynamics of communities and ecosystems. These eco‐evolutionary dynamics (EED) are likely to have substantial and quantifiable effects in restored habitats over timescales that are relevant for the conservation and restoration of small populations and threatened communities. Restored habitats may serve as “hotspots” for EED due to mismatches between transplanted genotypes and the restored environment, and novel interactions among lineages that do not share a coevolutionary history, both of which can generate strong selection for rapid evolutionary change that has immediate demographic consequences. Rapid evolution that influences population dynamics and community processes is likely to have particularly large effects during the establishment phase of restoration efforts. Finally, restoration activities and their associated long‐term monitoring programs provide outstanding opportunities for using eco‐evolutionary experimental approaches. Results from such studies will address questions about the effects of rapid evolutionary change on the ecological dynamics of populations and interacting species, while simultaneously providing critical, but currently overlooked, information for conservation practices.  相似文献   

8.
Food and drink consumption was found to be responsible for around 20–30% of environmental impacts. Environmental impacts occur during all stages of the food production chain. However, households influence these impacts with through their choice of diet and habits, thus directly affecting the environment through food-related energy consumption and waste generation. With the multiplication of local policies for sustainable consumption, it has become increasingly useful to gather information on the evolution of the ecological impacts associated with household food consumption. Dealing with the indicators of household consumption of fruits and vegetables will enable changes in the population's lifestyles and the effectiveness of local policies to be monitored.The aims of this article are twofold: to provide a conceptual framework on the purposes of ecological indicators of fruit and vegetable consumption (EIFVCs) and to provide a methodological approach for selecting and measuring the most relevant EIFVCs at a local scale. Considering the great diversity of ecological impacts, the large number of potential EIFVCs must be reduced to obtain fewer EIFVCs, but that are relevant at local scale. To be relevant, the EIFVCs must provide information on the three phases of consumption (acquisition, use, and disposal) and on the upstream and downstream phases of the consumption process; they should evaluate the more problematic ecological impacts at the local scale (level of concern); and they have to only point out the ecological impacts that households can significantly reduce through their consumption rates. To measure relevant EIFVCs, three approaches must be combined: monitoring the ecological impacts, measuring the material and energy fluxes associated with household consumption, and analysing the consumer behaviours that result in the observed ecological impacts.As an illustration, the methodology is applied to the Bordeaux Metropolitan Area (France). In this area, eleven EIFVCs seem relevant. The use of surveys characterises all eleven of the EIFVCs, despite the difficulty of establishing quantified relationships between household behaviours and measured ecological impacts. The measuring of fluxes is possible for eight of them, whereas the monitoring of ecological impacts is only feasible for two of them.  相似文献   

9.
Recent advances in the quantitative genetics of traits in wild animal populations have created new interest in whether natural selection, and genetic response to it, can be detected within long-term ecological studies. However, such studies have re-emphasized the fact that ecological heterogeneity can confound our ability to infer selection on genetic variation and detect a population''s response to selection by conventional quantitative genetics approaches. Here, I highlight three manifestations of this issue: counter gradient variation, environmentally induced covariance between traits and the correlated effects of a fluctuating environment. These effects are symptomatic of the oversimplifications and strong assumptions of the breeder''s equation when it is applied to natural populations. In addition, methods to assay genetic change in quantitative traits have overestimated the precision with which change can be measured. In the future, a more conservative approach to inferring quantitative genetic response to selection, or genomic approaches allowing the estimation of selection intensity and responses to selection at known quantitative trait loci, will provide a more precise view of evolution in ecological time.  相似文献   

10.
Population genetic data can provide valuable information on the demography of a species. For rare and elusive marine megafauna, samples for generating the data are traditionally obtained from tissue biopsies, which can be logistically difficult and expensive to collect and require invasive sampling techniques. Analysis of environmental DNA (eDNA) offers an alternative, minimally invasive approach to provide important genetic information. Although eDNA approaches have been studied extensively for species detection and biodiversity monitoring in metabarcoding studies, the potential for the technique to address population-level questions remains largely unexplored. Here, we applied “eDNA haplotyping” to obtain estimates of the intraspecific genetic diversity of a whale shark (Rhincodon typus) aggregation at Ningaloo reef, Australia. Over 2 weeks, we collected seawater samples directly behind individual sharks prior to taking a tissue biopsy sample from the same animal. Our data showed a 100% match between mtDNA sequences recovered in the eDNA and tissue sample for all 28 individuals sampled. In the seawater samples, >97% of all reads were assigned to six dominant haplotypes, and a clear dominant signal (~99% of sample reads) was recovered in each sample. Our study demonstrates accurate individual-level haplotyping from seawater eDNA. When DNA from one individual clearly dominates each eDNA sample, it provides many of the same opportunities for population genetic analyses as a tissue sample, potentially removing the need for tissue sampling. Our results show that eDNA approaches for population-level analyses have the potential to supply critical demographic data for the conservation and management of marine megafauna.  相似文献   

11.
Noninvasive faecal DNA sampling has the potential to provide a wealth of information necessary for monitoring and managing endangered species while eliminating the need to capture, handle or observe rare individuals. However, scoring problems, and subsequent genotyping errors, associated with this monitoring method remain a great concern as they can lead to misidentification of individuals and biased estimates. We examined a kit fox scat data set (353 scats; 80 genotypes) for genotyping errors using both genetic and GIS analyses, and evaluated the feasibility of combining both approaches to assess reliability of the faecal DNA results. We further checked the appropriateness of using faecal genotypes to study kit fox populations by describing information about foxes that we could deduce from the 'acceptable' scat genotypes, and comparing it to information gathered with traditional field techniques. Overall, genetic tests indicated that our data set had a low rate of genotyping error. Furthermore, examination of distributions of scat locations confirmed our data set was relatively error free. We found that analysing information on sex primer consistency and scat locations provided a useful assessment of scat genotype error, and greatly limited the amount of additional laboratory work that was needed to identify potentially 'false' scores. 'Acceptable' scat genotypes revealed information on sex ratio, relatedness, fox movement patterns, latrine use, and size of home range. Results from genetic and field data were consistent, supporting the conclusion that our data set had a very low rate of genotyping error and that this noninvasive method is a reliable approach for monitoring kit foxes.  相似文献   

12.
Analysis of genetic variation can provide insights into ecological and evolutionary diversification which, for commercially harvested species, can also be relevant to the implementation of spatial management strategies and sustainability. In comparison with other marine biodiversity hot spots, there has been less genetic research on the fauna of the southwest Indian Ocean (SWIO). This is epitomized by the lack of information for lethrinid fish, which support socioeconomically important fisheries in the region. This study combines comparative phylogeographic and population genetic analyses with ecological niche modeling to investigate historical and contemporary population dynamics of two species of emperor fish (Lethrinus mahsena and Lethrinus harak) across the SWIO. Both species shared similarly shallow phylogeographic patterns and modeled historical (LGM) habitat occupancies. For both species, allele frequency and kinship analyses of microsatellite variation revealed highly significant structure with no clear geographical pattern and nonrandom genetic relatedness among individuals within samples. The genetic patterns for both species indicate recurrent processes within the region that prevent genetic mixing, at least on timescales of interest to fishery managers, and the potential roles of recruitment variability and population isolation are discussed in light of biological and environmental information. This consistency in both historical and recurrent population processes indicates that the use of model species may be valuable in management initiatives with finite resources to predict population structure, at least in cases wherein biogeographic and ecological differences between taxa are minimized. Paradoxically, mtDNA sequencing and microsatellite analysis of samples from the Seychelles revealed a potential cryptic species occurring in sympatry with, and seemingly morphologically identical to, L. mahsena. BLAST results point to the likely misidentification of species and incongruence between voucher specimens, DNA barcodes, and taxonomy within the group, which highlights the utility and necessity of genetic approaches to characterize baseline biodiversity in the region before such model‐based methods are employed.  相似文献   

13.
Although the neural and genetic pathways underlying learning and memory formation seem strikingly similar among species of distant animal phyla, several more subtle inter- and intraspecific differences become evident from studies on model organisms. The true significance of such variation can only be understood when integrating this with information on the ecological relevance. Here, we argue that parasitoid wasps provide an excellent opportunity for multi-disciplinary studies that integrate ultimate and proximate approaches. These insects display interspecific variation in learning rate and memory dynamics that reflects natural variation in a daunting foraging task that largely determines their fitness: finding the inconspicuous hosts to which they will assign their offspring to develop. We review bioassays used for oviposition learning, the ecological factors that are considered to underlie the observed differences in learning rate and memory dynamics, and the opportunities for convergence of ecology and neuroscience that are offered by using parasitoid wasps as model species. We advocate that variation in learning and memory traits has evolved to suit an insect's lifestyle within its ecological niche.  相似文献   

14.
Fire seasons have become increasingly variable and extreme due to changing climatological, ecological, and social conditions. Earth observation data are critical for monitoring fires and their impacts. Herein, we present a whole-system framework for identifying and synthesizing fire monitoring objectives and data needs throughout the life cycle of a fire event. The four stages of fire monitoring using Earth observation data include the following: (1) pre-fire vegetation inventories, (2) active-fire monitoring, (3) post-fire assessment, and (4) multi-scale synthesis. We identify the challenges and opportunities associated with current approaches to fire monitoring, highlighting four case studies from North American boreal, montane, and grassland ecosystems. While the case studies are localized to these ecosystems and regional contexts, they provide insights for others experiencing similar monitoring challenges worldwide. The field of remote sensing is experiencing a rapid proliferation of new data sources, providing observations that can inform all aspects of our fire monitoring framework; however, significant challenges for meeting fire monitoring objectives remain. We identify future opportunities for data sharing and rapid co-development of information products using cloud computing that benefits from open-access Earth observation and other geospatial data layers.  相似文献   

15.
The increasing use of genetic information for the development of methods to study the diversity, distributions, and activities of protists in nature has spawned a new generation of powerful tools. For ecologists, one lure of these approaches lies in the potential for DNA sequences to provide the only immediately obvious means of normalizing the diverse criteria that presently exist for identifying and counting protists. A single, molecular taxonomy would allow studies of diversity across a broad range of species, as well as the detection and quantification of particular species of interest within complex, natural assemblages; goals that are not feasible using traditional methods. However, these advantages are not without their potential pitfalls and problems. Conflicts involving the species concept, disagreements over the true (physiological/ecological) meaning of genetic diversity, and a perceived threat by some that sequence information will displace knowledge regarding the morphologies, functions and physiologies of protistan taxa, have created debate and doubt regarding the efficacy and appropriateness of some genetic approaches. These concerns need continued discussion and eventual resolution as we move toward the irresistible attraction, and potentially enormous benefits, of the application of genetic approaches to protistan ecology.  相似文献   

16.
17.
Ecologically relevant genetic variation occurs in genes harbouring alleles that are adaptive in some environments but not in others. Analysis of this type of genetic variation in model organisms has made substantial progress, and is now being expanded to other species in order to better cover the diversity of plant life. Recent advances in connecting ecological and molecular studies in non-model species have been made with regard to edaphic and climatic adaptation, plant reproduction, life-history parameters and biotic interactions. New research avenues that increase biological complexity and ecological relevance by integrating ecological experiments with population genetic and functional genomic approaches provide new insights into the genetic basis of ecologically relevant variation.  相似文献   

18.
  1. Recent advances in molecular methods foster the documentation of small spatial scale biological diversity over large geographical areas. These advances allow to correctly record α-diversity, but also enable biomonitoring that describes intraspecific molecular diversity, providing valuable insights into the contemporary history of species. Such information is essential for the accurate monitoring of freshwater communities and provides a promising tool to identify conservation priorities at various spatial scales.
  2. Here, we combined morphological species determinations with genetic characterisation via DNA barcoding and species distribution modelling. We aimed to investigate whether closely related amphipod species occupying overlapping ecological niches and occurring in partial sympatry, demonstrate similar spatial patterns of intraspecific genetic diversity and share comparable population histories. Therefore, we characterised the amphipod fauna within the Kinzig catchment (1,058 km2, Hesse, Central Germany) that is a tributary of the Main River and part of the long-term ecological research network using genetics.
  3. Our genetic analysis revealed two more taxonomic entities than previously known. The most common species was Gammarus fossarum clade 11 (or type B), followed by Gammarus roeselii clade C, Gammarus pulex clade D, G. pulex clade B and a very rare previously unknown lineage within the G. fossarum-species complex, which we refer to as G. fossarum clade RMO. These five taxa differed in their intraspecific genetic diversity, with G. fossarum clade 11 demonstrating the highest diversity and having a prominent small-scale pattern with endemic haplotypes in headwater regions. Distributions were predicted for the three most abundant molecularly identified species.
  4. The upstream reaches maintained high intraspecific α- and β-diversity, pointing towards a more complex population structure of G. fossarum clade 11. This highlights the importance of considering intraspecific diversity for the conservation of individual species. DNA-based species distribution models shed light on species-specific habitat preferences, and showed spatial distribution patterns that supported ecological inference and conservation management. Barcoding specimens prior to modelling can increase robustness and performance of distribution models as juveniles can be incorporated, and cryptic species complexes disentangled.
  5. Our integrative study contributes to the further development of science-informed and holistically considered effective conservation measures. Some poorly dispersing hololimnic species may serve as representatives for our understanding of the natural history of the local communities in headwater regions—and their protection. Intraspecific genetic diversity should be considered in conservation management decisions as it can provide valuable information on past and present population demography, connectivity, and recovery processes of species—information that rarely can be achieved by traditional monitoring approaches.
  相似文献   

19.
为了给花苜蓿(Medicago ruthenica Trautv.)抗旱耐盐的生态适应性研究提供特异的遗传标记,在已公布的70对鹰嘴豆抗旱耐盐EST-SSR标记中筛选出稳定性好、多态性高的8对引物,并用这8对引物对挑选出的11个居群的286个个体进行扩增,获得111个等位基因。平均等位基因数为13.88;平均观察杂合度为0.497;平均预期杂合度为0.687;多态信息含量从0.313到0.883不等,平均值为0.649。以上结果表明,筛选出来的8个EST-SSR标记可以用于花苜蓿的遗传多样性分析,而且遗传多样性处于较高水平。多态性丰富的EST-SSR 引物适用于花苜蓿生态适应性进化分析,对揭示花苜蓿抗旱耐盐基因型的遗传变异和地理分布格局以及探讨花苜蓿抗旱耐盐的适应性分化机制有重要意义。  相似文献   

20.
A major research goal in microbial ecology is to understand the relationship between gene organization and function involved in environmental processes of potential interest. Given that more than an estimated 99% of microorganisms in most environments are not amenable to culturing, methods for culture-independent studies of genes of interest have been developed. The wealth of metagenomic approaches allows environmental microbiologists to directly explore the enormous genetic diversity of microbial communities. However, it is extremely difficult to obtain the appropriate sequencing depth of any particular gene that can entirely represent the complexity of microbial metagenomes and be able to draw meaningful conclusions about these communities. This review presents a summary of the metagenomic approaches that have been useful for collecting more information about specific genes. Specific subsets of metagenomes that focus on sequence analysis were selected in each metagenomic studies. This 'targeted metagenomics' approach will provide extensive insight into the functional, ecological and evolutionary patterns of important genes found in microorganisms from various ecosystems.  相似文献   

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