No apparent genetic bottleneck in the demographically declining European eel using molecular genetics and forward-time simulations

No apparent genetic bottleneck in the demographically declining European eel using molecular genetics and forward-time simulations

Reflexiones sobre ‘Occupy. The spatial dynamics of discourse in global protest movements’ de Luisa Martin Rojo

La publicación del libro Occupy. The spatial dynamics of discourse in global protest movements, editado por Luisa Martin Rojo abre un nuevo campo para los estudios del discurso en el que se otorga centralidad al espacio en un sentido dinámico. Por este motivo, como parte del foro e-conversa (promovido por la Asociación Internacional de Estudios sobre Discurso y Sociedad EDiSo; http://www.edisoportal.org/) se planteó la lectura del capítulo introductorio (cuya traducción al español se encuentra en este número de Discurso y Sociedad) y debatir sobre algunas de las cuestiones que en él se plantean. El resultado está formado por varias contribuciones que, tomando como punto de partida el texto de Martín Rojo, reflexionan, entre otros temas, sobre las prácticas espaciales, el papel de los medios de comunicación y las redes sociales, el nuevo sujeto político emergente, las formaciones contrahegemónicas, el multilingüismo, prácticas prefigurativas, etc. De este modo, este texto dialógico es una invitación a seguir pensando el análisis del discurso desde una perspectiva novedosa ligada al espacio / The publication of the volumen Occupy. The spatial dynamics of discourse in global protest movements, edited by Luisa Martín Rojo, opens up a new field of discourse studies in which the focus lies on space, in a dynamic sense. For this reason, and as part of the forum e-conversa (hosted by the International Association of Discourse Studies and Society (EDiSo); http://www.edisoportal.org/Ediso), it was suggested to read the introduction (the Spanish translation of which is included in this issue of Discurso y Sociedad) and to debate over some of the topics presented in the book. The result consists of several contributions which, by taking Martin Rojo’s text as the starting point, reflect on spatial practices, the role of mass media and social networks, the new emerging political subject, counter-hegemonic formations, multilingualism, and prefigurative practices, among other issues. Thus, this dialogic text is an invitation to continue thinking about discourse analysis from a new perspective linked to space

A resource of genome-wide single-nucleotide polymorphisms generated by RAD tag sequencing in the critically endangered European eel

Reduced representation genome sequencing such as restriction-site-associated DNA (RAD) sequencing is finding increased use to identify and genotype large numbers of single-nucleotide polymorphisms (SNPs) in model and nonmodel species. We generated a unique resource of novel SNP markers for the European eel using the RAD sequencing approach that was simultaneously identified and scored in a genome-wide scan of 30 individuals. Whereas genomic resources are increasingly becoming available for this species, including the recent release of a draft genome, no genome-wide set of SNP markers was available until now. The generated SNPs were widely distributed across the eel genome, aligning to 4779 different contigs and 19 703 different scaffolds. Significant variation was identified, with an average nucleotide diversity of 0.00529 across individuals. Results varied widely across the genome, ranging from 0.00048 to 0.00737 per locus. Based on the average nucleotide diversity across all loci, long-term effective population size was estimated to range between 132 000 and 1 320 000, which is much higher than previous estimates based on microsatellite loci. The generated SNP resource consisting of 82 425 loci and 376 918 associated SNPs provides a valuable tool for future population genetics and genomics studies and allows for targeting specific genes and particularly interesting regions of the eel genome

Sequencing, de novo annotation and analysis of the first Anguilla anguilla transcriptome: EeelBase opens new perspectives for the study of the critically endangered european eel

Background: Once highly abundant, the European eel (Anguilla anguilla L.; Anguillidae; Teleostei) is considered to be critically endangered and on the verge of extinction, as the stock has declined by 90-99% since the 1980s. Yet, the species is poorly characterized at molecular level with little sequence information available in public databases.\ud \ud Results: The first European eel transcriptome was obtained by 454 FLX Titanium sequencing of a normalized cDNA library, produced from a pool of 18 glass eels (juveniles) from the French Atlantic coast and two sites in the Mediterranean coast. Over 310,000 reads were assembled in a total of 19,631 transcribed contigs, with an average length of 531 nucleotides. Overall 36% of the contigs were annotated to known protein/nucleotide sequences and 35 putative miRNA identified.\ud \ud Conclusions: This study represents the first transcriptome analysis for a critically endangered species. EeelBase, a dedicated database of annotated transcriptome sequences of the European eel is freely available at http://compgen.bio.unipd.it/eeelbase. Considering the multiple factors potentially involved in the decline of the European eel, including anthropogenic factors such as pollution and human-introduced diseases, our results will provide a rich source of data to discover and identify new genes, characterize gene expression, as well as for identification of genetic markers scattered across the genome to be used in various applications

Language attitudes, linguistic authority and independence in 21st century Catalonia

peer-reviewedIn a context of increasing linguistic and cultural diversity and political uncertainty in Catalonia, this article reports on a research project which set out to explore the attitudes of members of independence organisations operating in the city of Girona toward the Catalan and Spanish languages. This study approaches language attitudes through the theoretical lens of linguistic authority, in particular, the concepts of anonymity and authenticity. The data, gathered from six focus groups, provide an insight on the nature of linguistic authority in contemporary Catalonia. Two themes emerge in the informants’ discussion of Catalan and Spanish: ‘twenty-first Century Catalanisme’ and ‘Embracing Linguistic Diversity’. The comments of the respondents indicate that, against the backdrop of the independence process in the region, bilingualism and multilingualism have become highly valued in the territory. In addition, this study suggests that a fuller understanding of the situation in Catalonia may be facilitated by qualitative approaches, which explore attitudes in-depth

Contesting language policy for asylum seekers in the Northern periphery: The story of Tailor F

This article is about navigating asylum, employment and language policy in a new country as an asylum seeker. Through the story of one individual, we show that profound inequalities are exacerbated when forced migrants are limited in their choice of language they might study or use. The individual is Tailor F, an Iraqi man seeking asylum, and the country is Finland, officially bilingual, with a majority language (Finnish) and a minority language (Swedish). Finland’s official bilingualism does not extend evenly to language education provided for asylum seekers, who are taught Finnish regardless of the region where they are placed. Upon arrival, Tailor F was housed in a reception centre for asylum seekers located in a Swedish-dominant rural area of the country. Through our linguistic ethnography we examine how he navigates multilingually in his early settlement, his current work and his online life. We relate his story to explicit and implicit official bilingualism in Finland and discuss his lived experiences in relation to the contexts of asylum policy and employment. Tailor F’s story shows how, through his practices, he has contested implicit language policy for asylum seekers in order to gain membership of the local Swedish-dominant community, achieve a sense of belonging, and potentially realise his aspirations for the future

Genetic diversity and local connectivity in the mediterranean red gorgonian coral after mass mortality events

Estimating the patterns of connectivity in marine taxa with planktonic dispersive stages is a challenging but crucial task because of its conservation implications. The red gorgonian Paramuricea clavata is a habitat forming species, characterized by short larval dispersal and high reproductive output, but low recruitment. In the recent past, the species was impacted by mass mortality events caused by increased water temperatures in summer. In the present study, we used 9 microsatellites to investigate the genetic structure and connectivity in the highly threatened populations from the Ligurian Sea (NW Mediterranean). No evidence for a recent bottleneck neither decreased genetic diversity in sites impacted by mass mortality events were found. Significant IBD pattern and high global F-ST confirmed low larval dispersal capability in the red gorgonian. The maximum dispersal distance was estimated at 20-60 km. Larval exchange between sites separated by hundreds of meters and between different depths was detected at each site, supporting the hypothesis that deeper subpopulations unaffected by surface warming peaks may provide larvae for shallower ones, enabling recovery after climatically induced mortality events

Geographically Widespread Swordfish Barcode Stock Identification: A Case Study of Its Application

Background: The swordfish (Xiphias gladius) is a cosmopolitan large pelagic fish inhabiting tempered and tropical waters and it is a target species for fisheries all around the world. The present study investigated the ability of COI barcoding to reliably identify swordfish and particularly specific stocks of this commercially important species. Methodology: We applied the classical DNA barcoding technology, upon a 682 bp segment of COI, and compared swordfish sequences from different geographical sources (Atlantic, Indian Oceans and Mediterranean Sea). The sequences of the 59 hyper-variable fragment of the control region (59dloop), were also used to validate the efficacy of COI as a stockspecific marker. Case Report: This information was successfully applied to the discrimination of unknown samples from the market, detecting in some cases mislabeled seafood products. Conclusions: The NJ distance-based phenogram (K2P model) obtained with COI sequences allowed us to correlate the swordfish haplotypes to the different geographical stocks. Similar results were obtained with 59dloop. Our preliminary data in swordfish Xiphias gladius confirm that Cytochrome Oxidase I can be proposed as an efficient species-specific marker that has also the potential to assign geographical provenance. This information might speed the samples analysis in commercia

The Effect of Recurrent Floods on Genetic Composition of Marble Trout Populations

A changing global climate can threaten the diversity of species and ecosystems. We explore the consequences of catastrophic disturbances in determining the evolutionary and demographic histories of secluded marble trout populations in Slovenian streams subjected to weather extremes, in particular recurrent flash floods and debris flows causing massive mortalities. Using microsatellite data, a pattern of extreme genetic differentiation was found among populations (global FST of 0.716), which exceeds the highest values reported in freshwater fish. All locations showed low levels of genetic diversity as evidenced by low heterozygosities and a mean of only 2 alleles per locus, with few or no rare alleles. Many loci showed a discontinuous allele distribution, with missing alleles across the allele size range, suggestive of a population contraction. Accordingly, bottleneck episodes were inferred for all samples with a reduction in population size of 3–4 orders of magnitude. The reduced level of genetic diversity observed in all populations implies a strong impact of genetic drift, and suggests that along with limited gene flow, genetic differentiation might have been exacerbated by recurrent mortalities likely caused by flash flood and debris flows. Due to its low evolutionary potential the species might fail to cope with an intensification and altered frequency of flash flood events predicted to occur with climate change