9,767 research outputs found
Charlie May Simon materials
No full textThis collection contains materials relating to Arkansas author Charlie May Simon
Metagenetic analysis of patterns of distribution and diversity of marine meiobenthic eukaryotes
No full textAim:Meiofaunal communities that inhabit the marine benthos offer unique opportunities to simultaneously study the macroecology of numerous phyla that exhibit different life-history strategies. Here, we ask: (1) if the macroecology of meiobenthic communities is explained mainly by dispersal constraints or by environmental conditions; and (2) if levels of meiofaunal diversity surpass existing estimates based on morphological taxonomy.Location:UK and mainland European coast.Methods:Next-generation sequencing techniques (NGS; Roche 454 FLX platform) using 18S nuclear small subunit ribosomal DNA (rDNA) gene. Pyrosequences were analysed using Amplicon Noise followed by chimera removal using Perseus.Results:Rarefaction curves revealed that sampling saturation was only reached at 15% of sites, highlighting that the bulk of meiofaunal diversity is yet to be discovered. Overall, 1353 OTUs were recovered and assigned to 23 different phyla. The majority of sampled sites had c. 60–70 unique operational taxonomic units (OTUs) per site, indicating high levels of beta diversity. The environmental parameters that best explained community structure were seawater temperature, geographical distance and sediment size, but most of the variability (R2 = 70%–80%) remains unexplained.Main conclusions:High percentages of endemic OTUs suggest that meiobenthic community composition is partly niche-driven, as observed in larger organisms, but also shares macroecological features of microorganisms by showing high levels of cosmopolitanism (albeit on a much smaller scale). Meiobenthic communities exhibited patterns of isolation by distance as well as associations between niche, latitude and temperature, indicating that meiobenthic communities result from a combination of niche assembly and dispersal processes. Conversely, isolation-by-distance patterns were not identified in the featured protists, suggesting that animals and protists adhere to radically different macroecological processes, linked to life-history strategies
Simon Nyakot
No full textabstract: Simon Nyakot left his village when he was six years old.
“Lost Boys Found” is an ongoing, interdisciplinary project that is collecting, recording and archiving the oral histories of the Lost Boys/Girls of Sudan. The collection is a work-in-progress, seeking to record the oral history of as many Lost Boys/Girls as are willing, and will be used in a future book.Age: 27Region: LakeThis picture and bio was donated to the Lost Boys Found project from The Arizona Lost Boys Cente
Cahiers Saint-Simon
No full texthttps://www.persee.fr/renderCollectionCover/simon.pngThe Société Saint-Simon was founded in 1972 in order to promote studies about the Duke of Saint-Simon (1675-1755), namely about the work, life, and thinking of the Mémoires’s author. Each year it issues a Cahier Saint-Simon. It contains the Acts of the annual Journée d’étude in Versailles, but also Notes and Documents, News of the Society and Book reviews.Fondée en 1972, la Société Saint-Simon a pour but de développer les études concernant l'oeuvre, la personne et la pensée du duc de Saint-Simon (1675-1755), l’auteur des Mémoires. Chaque année, paraît un numéro de Cahiers Saint-Simon contenant les actes de la journée annuelle de Versailles, ainsi que des Mélanges, des Notes et Documents et une Chronique bibliographique détaillée
Cahiers Saint-Simon
No full texthttps://www.persee.fr/renderCollectionCover/simon.pngThe Société Saint-Simon was founded in 1972 in order to promote studies about the Duke of Saint-Simon (1675-1755), namely about the work, life, and thinking of the Mémoires’s author. Each year it issues a Cahier Saint-Simon. It contains the Acts of the annual Journée d’étude in Versailles, but also Notes and Documents, News of the Society and Book reviews.Fondée en 1972, la Société Saint-Simon a pour but de développer les études concernant l'oeuvre, la personne et la pensée du duc de Saint-Simon (1675-1755), l’auteur des Mémoires. Chaque année, paraît un numéro de Cahiers Saint-Simon contenant les actes de la journée annuelle de Versailles, ainsi que des Mélanges, des Notes et Documents et une Chronique bibliographique détaillée
Simon Weir - The Sydney Surrealist
No full textExhibition catalogue of "Simon Weir - The Sydney Surrealist", Exhibition at Disorder Gallery, Darlinghurst NSW, Australia, in April 2024. The catalogue contains images of exhibited works and statements by the artist Simon Weir, the gallery Director Elliott Cole, and author and journalist Margie Smithurst
Animals, protists and bacteria share marine biogeographic patterns
No full textOver millennia, ecological and evolutionary mechanisms have shaped macroecological patterns across the tree of life. Research describing these patterns at both regional and global scales has traditionally focused on the study of metazoan species. Consequently, there is a limited understanding of cross-phylum biogeographic structuring and an escalating need to understand the macroecology of both microscopic and macroscopic organisms. Here we used environmental DNA (eDNA) metabarcoding to explore the biodiversity of marine metazoans, protists and bacteria along an extensive and highly heterogeneous coastline. Our results showed remarkably consistent biogeographic structure across the kingdoms of life despite billions of years of evolution. Analyses investigating the drivers of these patterns for each taxonomic kingdom found that environmental conditions (such as temperature) and, to a lesser extent, anthropogenic stressors (such as fishing pressure and pollution) explained some of the observed variation. Additionally, metazoans displayed biogeographic patterns that suggested regional biotic homogenization. Against the backdrop of global pervasive anthropogenic environmental change, our work highlights the importance of considering multiple domains of life to understand the maintenance and drivers of biodiversity patterns across broad taxonomic, ecological and geographical scales.</p
Detection of introduced and resident marine species using environmental DNA metabarcoding of sediment and water
No full textEnvironmental DNA (eDNA) surveys are increasingly being used for biodiversity monitoring, principally because they are sensitive and can provide high resolution community composition data. Despite considerable progress in recent years, eDNA studies examining how different environmental sample types can affect species detectability remain rare. Comparisons of environmental samples are especially important for providing best practice guidance on early detection and subsequent mitigation of non-indigenous species. Here we used eDNA metabarcoding of COI (cytochrome c oxidase subunit I) and 18S (nuclear small subunit ribosomal DNA) genes to compare community composition between sediment and water samples in artificial coastal sites across the United Kingdom. We first detected markedly different communities and a consistently greater number of distinct operational taxonomic units in sediment compared to water. We then compared our eDNA datasets with previously published rapid assessment biodiversity surveys and found excellent concordance among the different survey techniques. Finally, our eDNA surveys detected many non-indigenous species, including several newly introduced species, highlighting the utility of eDNA metabarcoding for both early detection and temporal / spatial monitoring of non-indigenous species. We conclude that careful consideration on environmental sample type is needed when conducting eDNA surveys, especially for studies assessing community change.</p
Second-generation environmental sequencing unmasks marine metazoan biodiversity
No full textBiodiversity is of crucial importance for ecosystem functioning, sustainability and resilience, but the magnitude and organization of marine diversity at a range of spatial and taxonomic scales are undefined. In this paper, we use second-generation sequencing to unmask putatively diverse marine metazoan biodiversity in a Scottish temperate benthic ecosystem. We show that remarkable differences in diversity occurred at microgeographical scales and refute currently accepted ecological and taxonomic paradigms of meiofaunal identity, rank abundance and concomitant understanding of trophic dynamics. Richness estimates from the current benchmarked Operational Clustering of Taxonomic Units from Parallel UltraSequencing analyses are broadly aligned with those derived from morphological assessments. However, the slope of taxon rarefaction curves for many phyla remains incomplete, suggesting that the true alpha diversity is likely to exceed current perceptions. The approaches provide a rapid, objective and cost-effective taxonomic framework for exploring links between ecosystem structure and function of all hitherto intractable, but ecologically important, communities
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