45 research outputs found

    Discovering hidden biodiversity: the use of complementary monitoring of fish diet based on DNA barcoding in freshwater ecosystems

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    Ecological monitoring contributes to the understanding of complex ecosystem functions. The diets of fish reflect the surrounding environment and habitats and may, therefore, act as useful integrating indicators of environmental status. It is, however, often difficult to visually identify items in gut contents to species level due to digestion of soft-bodied prey beyond visual recognition, but new tools rendering this possible are now becoming available. We used a molecular approach to determine the species identities of consumed diet items of an introduced generalist feeder, brown trout (Salmo trutta), in 10 Tasmanian lakes and compared the results with those obtained from visual quantification of stomach contents. We obtained 44 unique taxa (OTUs) belonging to five phyla, including seven classes, using the barcode of life approach from cytochrome oxidase I (COI). Compared with visual quantification, DNA analysis showed greater accuracy, yielding a 1.4-fold higher number of OTUs. Rarefaction curve analysis showed saturation of visually inspected taxa, while the curves from the DNA barcode did not saturate. The OTUs with the highest proportions of haplotypes were the families of terrestrial insects Formicidae, Chrysomelidae, and Torbidae and the freshwater Chironomidae. Haplotype occurrence per lake was negatively correlated with lake depth and transparency. Nearly all haplotypes were only found in one fish gut from a single lake. Our results indicate that DNA barcoding of fish diets is a useful and complementary method for discovering hidden biodiversity. In this paper sequence-based DNA barcoding was applied to determine the diet of a generalist predator (brown trout, Salmo trutta) based on gut analyses. Subsequently, the results were compared with data derived from visual inspection. Based on our results, we discuss the potential of using prey organisms in fish gut contents as a supplementary monitoring tool to reveal hidden biodiversity

    Increased percentage of L-selectin+ and ICAM-1+ peripheral blood CD4+/CD8+ T cells in active Graves' ophthalmopathy.

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    The purpose of the study was to evaluate the percentage of CD4+/CD8+ peripheral T cells expressing CD62L+ and CD54+ in patients with Graves' disease and to assess if these estimations could be helpful as markers of active ophthalmopathy. The study was carried out in 25 patients with Graves' disease (GD) divided into 3 groups: 1/ 8 patients with active Graves' ophthalmopathy (GO) (CAS 3-6, GO complaints pound 1 year), 2/ 9 patients with hyperthyroid GD without symptoms of ophthalmopathy (GDtox) and 3/ 8 patients with euthyroid GD with no GO symptoms (GDeu). The control group consisted of 15 healthy volunteers age and sex matched to groups 1-3. The expression of lymphocyte adhesion molecules was evaluated by using three-color flow cytometry. In GO group the percentage of CD8+CD54+, CD8+CD62L+, CD4+CD54+ and CD4+CD62L+ T cells was significantly higher as compared to controls (p<0.001, p<0.05, p<0.01, p<0.001 respectively). The percentage of CD8+CD54+ T lymphocytes was also elevated in GO group in comparison to hyperthyroid GD patients (p< 0.05). CD4+CD62L+ and CD8+CD54+ percentages were also increased in GDtox and GDeu as compared to controls. We found a positive correlation between the TSHRab concentration and the percentage of CD8+CD62L+ T cells in all studied groups (r= 0.39, p<0.05) and between the TSHRab level and CAS (r= 0.77, p<0.05). The increased percentage of CD8+CD54+ and CD8+CD62L+ T cells in patients with Graves' ophthalmopathy may be used as a marker of immune inflammation activity

    Global patterns and drivers of ecosystem functioning in rivers and riparian zones

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    River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.peerReviewe

    Shared vision, shared responsibility : the vertical integration of information literacy across the zoology curriculum

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    This paper tells the story of how a shared vision and shared responsibility between the Library and the School of Zoology at the University of Tasmania has led to the vertical integration of information literacy into the Zoology curriculum. Lecturers have embedded meaningful and stimulating learning activities into coursework, deliberately aimed at developing students’ information literacy. Students require sound information skills to undertake these activities; these skills are taught by the Liaison Librarian during specially tailored workshops incorporated into the unit teaching. Activities include: a first-year introduction to information skills and the scholarly information infrastructure; second/third year projects that require students to find 'the science' behind popular wildlife documentaries and to explore issues and controversies of scholarly communication; the introduction of EndNote to third-year students to manage information for their major research project; and advanced skills for Honours students to undertake major literature searches and manage information using EndNote. This paper discusses: the value of contributions from the different perspectives of librarians and lecturers; the importance of an iterative, incremental approach to developing students’ information literacy for lifelong learning; what students think; and work that still needs to be done

    River conservation in a changing world: invertebrate diversity and spatial prioritisation in south-eastern coastal Australia

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    Concentration of human populations with likely impacts of climate change present major challenges for river conservation in the south-eastern coastal region of Australia. Quantitative methods for spatial prioritisation of conservation actions can play a major role in meeting these challenges. We examined how these methods may be applied to help plan for potential impacts of climate change in the region, using macroinvertebrate assemblages as surrogates of river biodiversity. Environmental gradients explaining broad-scale patterns in the composition of macroinvertebrate assemblages are well represented in protected areas; however, their effectiveness for conserving river biodiversity with climate change depends on linking management inside and outside protected areas. Projected increases in temperature and sea level may be used to prioritise conservation to counter likely major impacts in high-altitude zones and the coastal fringes, whereas elsewhere, considerable uncertainty remains in the absence of better downscaled projections of rainfall. Applying such spatial prioritisations using biodiversity surrogates could help river-focussed conservation around the world. </jats:p
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