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101.
Caspar A. Hallmann Theo Zeegers Roel van Klink Rikjan Vermeulen Paul van Wielink Henk Spijkers Jurriën van Deijk Wouter van Steenis Eelke Jongejans 《Insect Conservation and Diversity》2020,13(2):127-139
- Recently, reports of insect declines prompted concerns with respect to the state of insects at a global level. Here, we present the results of longer‐term insect monitoring from two locations in the Netherlands: nature development area De Kaaistoep and nature reserves near Wijster.
- Based on data from insects attracted to light in De Kaaistoep, macro‐moths (macro‐Lepidoptera), beetles (Coleoptera), and caddisflies (Trichoptera) have declined in the mean number of individuals counted per evening over the period of 1997–2017, with annual rates of decline of 3.8, 5.0 and 9.2%, respectively. Other orders appeared stable [true bugs (Hemiptera: Heteroptera and Auchenorrhyncha) and mayflies (Ephemeroptera)] or had uncertainty in their trend estimate [lacewings (Neuroptera)].
- Based on 48 pitfall traps near Wijster, ground beetles (Coleoptera: Carabidae) showed a mean annual decline of 4.3% in total numbers over the period of 1985–2016. Nonetheless, declines appeared stronger after 1995.
- For macro‐moths, the mean of the trends of individual species was comparable to the annual trend in total numbers. Trends of individual ground beetle species, however, suggest that abundant species performed worse than rare ones.
- When translated into biomass estimates, our calculations suggest a reduction in total biomass of approximately 61% for macro‐moths as a group and at least 42% for ground beetles, by extrapolation over a period of 27 years. Heavier ground beetles and macro‐moths did not decline more strongly than lighter species, suggesting that heavy species did not contribute disproportionately to biomass decline.
- Our results broadly echo recent reported trends in insect biomass in Germany and elsewhere.
102.
- Bumble bees are declining globally, largely due to habitat loss driven by agricultural intensification. Within agriculturally dominated landscapes, semi‐natural habitats (e.g. meadows, wetland edges) are fragmented, increasing the value of uncropped agricultural field margins for providing a source of food, nesting, and hibernation resources to bumble bees.
- We compared bumble bee communities sampled in agricultural field margins and semi‐natural habitats across Southwestern Ontario, Canada in order to assess differences in habitat quality. We then examined the effect of floral resources and soil characteristics on the bumble bee communities present in each site, independent of the habitat type classification.
- Our data revealed that bumble bee abundance, diversity, and community composition did not differ between habitat types. However, when examined independently of habitat type, bumble bee abundance and diversity increased with floral abundance, floral diversity, the number of rodent holes, and sandy soil texture.
- These results suggest that agricultural field margins are not inherently degraded bumble bee habitat and have the potential to provide food and nesting resources comparable to semi‐natural habitats in a fragmented agricultural landscape. Ensuring field margins contain the necessary floral resources and soil characteristics for bumble bees has implications for conservation and mitigating habitat loss caused by the agricultural fields themselves.
103.
Flvio Siqueira de Castro Pedro Giovni Da Silva Ricardo Solar Geraldo Wilson Fernandes Frederico de Siqueira Neves 《Insect Conservation and Diversity》2020,13(4):393-403
- We investigated the patterns of taxonomic (TD) and functional (FD) α and β‐diversities of ants in a mountainous landscape along three dimensions, namely one temporal (seasonal) and two spatial dimensions: between habitats – grassland and forest habitats (horizontal), and among elevation bands (vertical). In addition, we tested the effects of environmental variables (mean elevation and temperature, and normalised difference vegetation index – NDVI) on taxonomic and functional α‐ and β‐diversities.
- β diversities among the two spatial dimensions are the main components of TD. Conversely, FD is almost entirely composed by the α‐diversity component, with a very low contribution of β‐diversity.
- Regarding environmental drivers, the decrease in temperature caused by increased elevations and seasonal variations had a negative effect on taxonomic α‐diversity. There were no effects of environmental variables on ant functional α‐diversity.
- Despite the high turnover of ant species occurring along spatial dimensions, the communities were functionally redundant. The changes in species richness and composition patterns in this mountain were strongly influenced by variables correlated with elevation and habitat structure.
- Species composition changed across all dimensions, but the core traits and functions remained unchanged. Differences observed in the composition of ant communities over relatively short geographic distances highlight the importance to conserve the entire mountain, ensuring the maintenance of the ant diversity and associated ecosystem functions.
104.
David L. J. Vendrami Michele De Noia Luca Telesca Eva‐Maria Brodte Joseph I. Hoffman 《Evolutionary Applications》2020,13(8):2130-2142
The three mussel species comprising the Mytilus complex are widespread across Europe and readily hybridize when they occur in sympatry, resulting in a mosaic of populations with varying genomic backgrounds. Two of these species, M. edulis and M. galloprovincialis, are extensively cultivated across Europe, with annual production exceeding 230,000 tonnes. The third species, M. trossulus, is considered commercially damaging as hybridization with this species results in weaker shells and poor meat quality. We therefore used restriction site associated DNA sequencing to generate high‐resolution insights into the structure of the Mytilus complex across Europe and to resolve patterns of introgression. Inferred species distributions were concordant with the results of previous studies based on smaller numbers of genetic markers, with M. edulis and M. galloprovincialis predominating in northern and southern Europe respectively, while introgression between these species was most pronounced in northern France and the Shetland Islands. We also detected traces of M. trossulus ancestry in several northern European populations, especially around the Baltic and in northern Scotland. Finally, genome‐wide heterozygosity, whether quantified at the population or individual level, was lowest in M. edulis, intermediate in M. galloprovincialis, and highest in M. trossulus, while introgression was positively associated with heterozygosity in M. edulis but negatively associated with heterozygosity in M. galloprovincialis. Our study will help to inform mussel aquaculture by providing baseline information on the genomic backgrounds of different Mytilus populations across Europe and by elucidating the effects of introgression on genome‐wide heterozygosity, which is known to influence commercially important traits such as growth, viability, and fecundity in mussels. 相似文献
105.
Fisheries‐induced evolution (FIE) can result when harvest imposes artificial selection on variation in heritable phenotypic traits. While there is evidence for FIE, it remains difficult to disentangle the contributions of within‐generation demographic adjustment, phenotypic plasticity, and genetic adaption to observed changes in life history traits. We present evidence for FIE using dozens of Coho salmon (Oncorhynchus kisutch) populations in which males adopt one of two age‐invariant, heritable life history tactics: most mature as large three‐year‐old “hooknose” and typically fight for spawning opportunities, while some mature as small two‐year‐old “jacks” and fertilize eggs through sneaking. The closure of a fishery targeting three‐year‐old fish provided an experimental test of the prediction that fishery‐imposed selection against hooknose males drives an evolutionary increase in the proportion of males adopting the jack tactic. The data support the prediction: 43 of 46 populations had higher jack proportions during than after the fishery. The data further suggest that changes in jack proportion were not solely the result of demographic adjustments to harvest. We suggest that systems where fisheries differentially exploit phenotypically discrete, age‐invariant life histories provide excellent opportunities for detecting FIE. 相似文献
106.
Kerry Reid John Carlos Garza Steven R. Gephard Adalgisa Caccone David M. Post Eric P. Palkovacs 《Evolutionary Applications》2020,13(4):652-664
Secondary contact may have important implications for ecological and evolutionary processes; however, few studies have tracked the outcomes of secondary contact from its onset in natural ecosystems. We evaluated an anadromous alewife (Alosa pseudoharengus ) reintroduction project in Rogers Lake (Connecticut, USA), which contains a landlocked alewife population that was isolated as a result of colonial‐era damming. After access to the ocean was restored, adult anadromous alewife were stocked into the lake. We assessed anadromous juvenile production, the magnitude and direction of introgression, and the potential for competition between ecotypes. We obtained fin clips from all adult alewife stocked into the lake during the restoration and a sample of juveniles produced in the lake two years after the stocking began. We assessed the ancestry of juveniles using categorical assignment and pedigree reconstruction with newly developed microhaplotype genetic markers. Anadromous alewives successfully spawned in the lake and hybridized with the landlocked population. Parentage assignments revealed that male and female anadromous fish contributed equally to juvenile F1 hybrids. The presence of landlocked backcrosses shows that some hybrids were produced within the first two years of secondary contact, matured in the lake, and reproduced. Therefore, introgression appears directional, from anadromous into landlocked, in the lake environment. Differences in estimated abundance of juveniles of different ecotypes in different habitats were also detected, which may reduce competition between ecotypes as the restoration continues. Our results illustrate the utility of restoration projects to study the outcomes of secondary contact in real ecosystems. 相似文献
107.
Random sampling is an important statistical assumption, but virtually impossible when sampling a wild species as we cannot know where all the individuals exist. While interpopulation or intrataxa sampling methods have been developed, there are currently few intrataxon sampling methods to objectively decide where to sample wild taxa. We suggest a new sampling method which computes appropriate sampling locations from coordinates, assuming geographical autocorrelation of phylogeny within a taxon (isolation‐by‐distance). The computed locations encompass the highest genetic diversity, providing a genetically representative sample. In addition, it can utilize presence/absence information during sampling to reoptimize sampling scheme. Comparing to the single existing method of the similar purpose, the merits of ours is unnecessity of environmental data resulting in easy application, and is theoretically deduced. We tested this method using published phylogeographical data. The test result was generally encouraging, but the method failed where species showed uniform genetic structure or recent distribution expansion which violate the assumption of geographical autocorrelation of phylogeny. Though simple, our method constructs a methodological and statistical foundation for sampling wild species, and is applicable to revising taxonomic study and conservation biology. 相似文献
108.
109.
Shama Prasada Kabekkodu Vaibhav Shukla Vinay Koshy Varghese Divya Adiga Padacherri Vethil Jishnu Sanjiban Chakrabarty Kapaettu Satyamoorthy 《Wiley interdisciplinary reviews. RNA》2020,11(2)
MiRNAs are class of noncoding RNA important for gene expression regulation in many plants, animals and viruses. MiRNA clusters contain a set of two or more miRNA encoding genes, transcribed together as polycistronic miRNAs. Currently, there are approximately 159 miRNA clusters reported in the human genome consisting of miRNAs ranging from two or more miRNA genes. A large proportion of clustered miRNAs resides in and around the fragile sites or cancer associated genomic hotspots and plays an important role in carcinogenesis. Altered expression of miRNA cluster can be pro‐tumorigenic or anti‐tumorigenic and can be targeted for clinical management of cancer. Over the past few years, manipulation of miRNA clusters expression is attempted for experimental purpose as well as for diagnostic, prognostic and therapeutic applications in cancer. Re‐expression of miRNAs by epigenetic therapy, genome editing such as clustered regulatory interspaced short palindromic repeats (CRISPR) and miRNA mowers showed promising results in cancer therapy. In this review, we focused on the potential of miRNA clusters as a biomarker for diagnosis, prognosis, targeted therapy as well as strategies for modulating their expression in a therapeutic context. This article is categorized under:
- Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs
- RNA Processing > Processing of Small RNAs
- RNA in Disease and Development > RNA in Disease
- Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs
110.
Charith Raj Adkar‐Purushothama Jean‐Pierre Perreault 《Wiley interdisciplinary reviews. RNA》2020,11(2)
Viroids are one of the most enigmatic highly structured, circular, single‐stranded RNA phytopathogens. Although they are not known to code for any peptide, viroids induce visible symptoms in susceptible host plants that resemble those associated with many plant viruses. It is known that viroids induce disease symptoms by direct interaction with host factors; however, the precise mechanism by which this occurs remains poorly understood. Studies on the host's responses to viroid infection, host susceptibility and nonhost resistance have been underway for several years, but much remains to be done in order to fully understand the complex nature of viroid–host interactions. Recent progress using molecular biology techniques combined with computational algorithms, in particular evidence of the role of viroid‐derived small RNAs in the RNA silencing pathways of a disease network, has widened the knowledge of viroid pathogenicity. The complexity of viroid–host interactions has been revealed in the past decades to include, but not be limited to, the involvement of host factors, viroid structural complexity, and viroid‐induced ribosomal stress, which is further boosted by the discovery of long noncoding RNAs (lncRNAs). In this review, the current understanding of the viroid–host interaction has been summarized with the goal of simplifying the complexity of viroid biology for future research. This article is categorized under:
- RNA in Disease and Development > RNA in Disease