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The mitochondrial genomes of Ancylostoma caninum and Bunostomum phlebotomum – two hookworms of animal health and zoonotic importance
Get PDFBackground: Hookworms are blood-feeding nematodes that parasitize the small intestines of many
mammals, including humans and cattle. These nematodes are of major socioeconomic importance and
cause disease, mainly as a consequence of anaemia (particularly in children or young animals), resulting in
impaired development and sometimes deaths. Studying genetic variability within and among hookworm
populations is central to addressing epidemiological and ecological questions, thus assisting in the control
of hookworm disease. Mitochondrial (mt) genes are known to provide useful population markers for
hookworms, but mt genome sequence data are scant.
Results: The present study characterizes the complete mt genomes of two species of hookworm,
Ancylostoma caninum (from dogs) and Bunostomum phlebotomum (from cattle), each sequenced (by 454
technology or primer-walking), following long-PCR amplification from genomic DNA (~20–40 ng) isolated
from individual adult worms. These mt genomes were 13717 bp and 13790 bp in size, respectively, and
each contained 12 protein coding, 22 transfer RNA and 2 ribosomal RNA genes, typical for other
secernentean nematodes. In addition, phylogenetic analysis (by Bayesian inference and maximum
likelihood) of concatenated mt protein sequence data sets for 12 nematodes (including Ancylostoma
caninum and Bunostomum phlebotomum), representing the Ascaridida, Spirurida and Strongylida, was
conducted. The analysis yielded maximum statistical support for the formation of monophyletic clades for
each recognized nematode order assessed, except for the Rhabditida.
Conclusion: The mt genomes characterized herein represent a rich source of population genetic markers
for epidemiological and ecological studies. The strong statistical support for the construction of
phylogenetic clades and consistency between the two different tree-building methods employed indicate
the value of using whole mt genome data sets for systematic studies of nematodes. The grouping of the
Spirurida and Ascaridida to the exclusion of the Strongylida was not supported in the present analysis, a
finding which conflicts with the current evolutionary hypothesis for the Nematoda based on nuclear
ribosomal gene data.© 2009 Jex et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published pdf.NHM Repositor
A revision of Peltariosilis Wittmer (Coleoptera: Cantharidae), a surprisingly diverse Amazonian radiation
Get PDFPeltariosilis Wittmer, 1952 is a South American Silinae genus characterised by the highly modified male pronotum and scutellum with a remarkable lamellar projection. Six species were previously recognised. The study of numerous specimens from previously unsampled localities and the revision of previously studied material shows that Peltariosilis is far more diverse than previously recognised. 15 species are here recognised as valid, nine of which are described as new: P. brancuccii, P. brunneoapicalis, P. cleidecostae, P. diversicollis, P. flavicornis, P. gracilicornis, P. major, P. orientalis and P. parviscutellaris spp. nov. A comparative study and new morphological terminologies are introduced for pronotum, scutellum and male genitalia. All Peltariosilis species are described and illustrated, including the first illustration of a female pronotum, and an identification key is provided. A map is given, including records of all known Peltariosilis, showing a distribution confined to the Amazonian subregion (Suriname, French Guiana, N Brazil, E Peru and NE Bolivia). The identity of the type species P. scutulata (Wittmer, 1952), hitherto considered as broadly distributed and highly variable, is addressed through study of their type series and additional specimens from widespread localities.Copyrights: Papéis Avulsos de Zoologia. The journal is licensed under CC-BY Creative Commons license. Responsibility: The scientific content and the opinions expressed in the manuscript are the sole responsibility of the author(s). The attached file is the published pdf. http://www.revistas.usp.br/paz/article/view/163558/159642NHM Repositor
Evolutionary history of the Galápagos Rail revealed by ancient mitogenomes and modern samples
Get PDFThe biotas of the Galápagos Islands are one of the best studied island systems and have
provided a broad model for insular species’ origins and evolution. Nevertheless, some locally
endemic taxa, such as the Galápagos Rail Laterallus spilonota, remain poorly characterized. Owing to
its elusive behavior, cryptic plumage, and restricted distribution, the Galápagos Rail is one of the
least studied endemic vertebrates of the Galapagos Islands. To date, there is no genetic data for this
species, leaving its origins, relationships to other taxa, and levels of genetic diversity uncharacterized.
This lack of information is critical given the adverse fate of island rail species around the world in the
recent past. Here, we examine the genetics of Galápagos Rails using a combination of mitogenome
de novo assembly with multilocus nuclear and mitochondrial sequencing from both modern and
historical samples. We show that the Galápagos Rail is part of the “American black rail clade”,
sister to the Black Rail L. jamaicensis, with a colonization of Galápagos dated to 1.2 million years
ago. A separate analysis of one nuclear and two mitochondrial markers in the larger population
samples demonstrates a shallow population structure across the islands, possibly due to elevated
island connectivity. Additionally, birds from the island Pinta possessed the lowest levels of genetic
diversity, possibly reflecting past population bottlenecks associated with overgrazing of their habitat
by invasive goats. The modern and historical data presented here highlight the low genetic diversity
in this endemic rail species and provide useful information to guide conservation efforts.2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).NHM Repositor
An overlooked contributor to palaeontology—the preparator Richard Hall (b. 1839) and his work on an armoured dinosaur and a giant sea dragon
Get PDFThe work of Richard Hall, a fossil preparator at the British Museum (Natural History) in the late 19th century, has been largely unrecorded. It included the excavation, preparation and restoration of two important specimens: the dinosaur Polacanthus foxii and the ichthyosaur Temnodontosaurus platyodon. The painstaking reconstruction of the dorsal shield of Polacanthus took seven years to complete and enabled a supplemental note redescribing the specimen to be published in 1887. The significance of the discovery in 1898 of the Temnodontosaurus to the town of Stockton in Warwickshire was such that it featured in an article in Nature. It has entered the local folklore and remains celebrated on the town’s road signage and features as the logo of Stockton Primary School.Issues older than two years are freely available from the GCG website (www.geocurator.org) via a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public Licence (CC BY-NC-ND 4.0: https://creativecommons.org/licenses/by-nc-nd/4.0/). Attribution should follow standard academic format, with the author(s) and year and link to a full reference. The attached file is the published pdf.NHM Repositor
The influence of fractionation of REE-enriched minerals on the zircon partition coefficients
Get PDFZircon is widely used to simulate melt generation, migration and evolution within the crust and mantle. The achievable performance of melt modelling generally depends on the availability of reliable trace element partition coefficients (D). However, a large range of DREE values for zircon from natural samples and experimental studies has been reported, with values spanning up to 3 orders of magnitude. Unfortunately, a gap of knowledge on this variability is evident. In this study we model the crystallization processes of common REE-bearing minerals from granitic melts and show that the measured zircon DREE would be elevated if there is crystallization of REE-enriched minerals subsequent to zircon. Nevertheless, compared to zircon DREE values measured from experimental studies, this mechanism appears to have a less significant influence on those from natural granite samples since the quantity of crystallized REE-enriched minerals is very low in natural magmatic systems and/or most of them crystallize prior to zircon. Combined with recently published studies, this work supports that analysis of natural zircon/host groundmass pairs provides more robust DREE values applicable to natural systems than those measured from experimental studies, which can be used to constrain the provenance of detrital zircons.This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. It is available as an open access article under a Creative Commons Licence https://creativecommons.org/licenses/by-nc-nd/4.0/.NHM Repositor
PREDICTIVE ESTIMATE OF Ti-Zr PLACER DEPOSITS IN MESOZOIC AND CENOZOIC SEDIMENTS AT NW MARGINS OF THE ZAYSAN BASIN, EAST KAZAKHSTAN
No full textDuring the research of orographic, geological and geomorphological characteristics of the Zaysan
basin area aiming to identify targeting factors of Ti-Zr alluvial deposits it has been established that the following
special favourable conditions are required for their formation: neighbouring occurrence of magmatic rocks with
Ti-Zr credit; well-formed deep chemical weathering crust, which has facilitated the release of ore minerals; alluvial,
proluvial limnic hydrodynamic conditions for transportation, segregation and concentration of Ti and Zr minerals;
availability of local structural particular qualities (tectonic layers, basins), which have prevented the deposits from
washing out during transgression and regression of the Zaysan paleo-lake. It has been established that well-known
Ti-Zr deposits in the north-west margin areas of the Zaysan basin are geomorphologically located in gentle slope,
non-segmented plains of subaerial denudation of 400–700m altitude, within the littoral zone of the Zaysan paleolake. The orographic representation of modern relief of the region have been established, stratigraphic positions of
Mesozoic and Cenozoic placer deposits were determined, and an area for prospecting of new Ti-Zr deposits was
identified.© National Academy of Sciences of the Republic of Kazakhstan, 2019. This is an open access journal. The attached file is the published pdf.NHM Repositor
Fine-scale appendage structure of the Cambrian trilobitomorph Naraoia spinosa and its ontogenetic and ecological implications
Get PDFTrilobitomorphs are a species-rich Palaeozoic arthropod assemblage that unites trilobites with several other lineages that share similar appendage structure. Post-embryonic development of the exoskeleton is well documented for some trilobitomorphs, especially trilobites, but little is known of the ontogeny of their soft parts, limiting understanding of their autecology. Here, we document appendage structure of the Cambrian naraoiid trilobitomorph Naraoia spinosa by computed microtomography, resulting in three-dimensional reconstructions of appendages at both juvenile and adult stages. The adult has dense, strong spines on the protopods of post-antennal appendages, implying a predatory/scavenging behaviour. The absence of such gnathobasic structures, but instead tiny protopodal bristles and a number of endopodal setae, suggests a detritus-feeding strategy for the juvenile. Our data add strong morphological evidence for ecological niche shifting by Cambrian arthropods during their life cycles. A conserved number of appendages across the sampled developmental stages demonstrates that Naraoia ceased budding off new appendages by the mid-juvenile stage.© 2019 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution
License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original
author and source are credited. The attached file is the published pdf.NHM Repositor
The Diversity of Venom: The Importance of Behavior and Venom System Morphology in Understanding Its Ecology and Evolution
Get PDFVenoms are one of the most convergent of animal traits known, and encompass a much greater taxonomic and functional diversity than is commonly appreciated. This knowledge gap limits the potential of venom as a model trait in evolutionary biology. Here, we summarize the taxonomic and functional diversity of animal venoms and relate this to what is known about venom system morphology, venom modulation, and venom pharmacology, with the aim of drawing attention to the importance of these largely neglected aspects of venom research. We find that animals have evolved venoms at least 101 independent times and that venoms play at least 11 distinct ecological roles in addition to predation, defense, and feeding. Comparisons of different venom systems suggest that morphology strongly influences how venoms achieve these functions, and hence is an important consideration for understanding the molecular evolution of venoms and their toxins. Our findings also highlight the need for more holistic studies of venom systems and the toxins they contain. Greater knowledge of behavior, morphology, and ecologically relevant toxin pharmacology will improve our understanding of the evolution of venoms and their toxins, and likely facilitate exploration of their potential as sources of molecular tools and therapeutic and agrochemical lead compounds.© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). The attached file is the published pdf.NHM Repositor
The genome sequence of the eastern grey squirrel, Sciurus carolinensis Gmelin, 1788
No full textCopyright: © 2020 Mead D et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.We present a genome assembly from an individual male Sciurus carolinensis (the eastern grey squirrel; Vertebrata; Mammalia; Eutheria; Rodentia; Sciuridae). The genome sequence is 2.82 gigabases in span. The majority of the assembly (92.3%) is scaffolded into 21 chromosomal-level scaffolds, with both X and Y sex chromosomes assembled.Copyright: © 2020 Mead D et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published pdf.NHM Repositor
Marine hotspots of activity inform protection of a threatened community of pelagic species in a large oceanic jurisdiction
No full textRemote oceanic islands harbour unique biodiversity, especially of species that rely on the marine trophic resources around their breeding islands. Identifying marine areas used by such species is essential to manage and limit processes that threaten these species. The Tristan da Cunha territory in the South Atlantic Ocean hosts several endemic and globally threatened seabirds, and pinnipeds; how they use the waters surrounding the islands must be considered when planning commercial activities. To inform marine management in the Tristan da Cunha Exclusive Economic Zone (EEZ), we identified statistically significant areas of concentrated activity by collating animal tracking data from nine seabirds and one marine mammal. We first calculated the time that breeding adults of the tracked species spent in 10 × 10 km cells within the EEZ, for each of four seasons to account for temporal variability in space use. By applying a spatial aggregation statistic over these grids for each season, we detected areas that are used more than expected by chance. Most of the activity hotspots were either within 100 km of breeding colonies or were associated with seamounts, being spatially constant across several seasons. Our simple and effective approach highlights important areas for pelagic biodiversity that will benefit conservation planning and marine management strategies.This is the peer reviewed version of the following article: Requena, S., Oppel, S., Bond, A.L., Hall, J., Cleeland, J., Crawford, R.J.M., Davies, D., Dilley, B.J., Glass, T., Makhado, A., Ratcliffe, N., Reid, T.A., Ronconi, R.A., Schofield, A., Steinfurth, A., Wege, M., Bester, M. and Ryan, P.G. (2020), Marine hotspots of activity inform protection of a threatened community of pelagic species in a large oceanic jurisdiction. Anim Conserv. doi:10.1111/acv.12572, which has been published in final form at https://doi.org/10.1111/acv.12572. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
The attached file is the final approved author manuscript version, you are advised to consult the publisher’s version if you wish to cite from it.NHM Repositor