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Various Gallus varius hybrids: variation in junglefowl hybrids and Darwin's interest in them
Get PDFHybrids between Green Junglefowl Gallus varius and domestic fowl G. gallus domesticus confused several 19th-century ornithologists. The plumage of these hybrids is so unlike the colours and patterns of either of the parent species that they were considered to be distinct species: G. aeneusTemminck, 1825; G. temminckiiGray, 1849; and G. violaceusKelsall, 1891. Darwin wanted to understand if G. aeneus and G. temminckii were hybrids or species, as part of his research on the origin of the domestic chicken. His view was that all domesticated fowl have a single wild ancestor, Red Junglefowl G. gallus (formerly G. bankiva). A hybrid specimen now present in the bird collection of the Natural History Museum at Tring played an important role in Darwin's reasoning and, although the conclusions he drew from this specimen were incorrect, his single-ancestor origin theory for domesticated fowl stands.
‘These hybrids were at one time thought to be specifically distinct, and were named G. aeneus. Mr. Blyth and others believe that the G. Temminckii is a similar hybrid' (Darwin 1868a: 234–235).© 2019 The Authors; This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The attached file is the published pdf.NHM Repositor
A new species of Bicurta Sheng et al. from China (Hymenoptera, Ichneumonidae, Collyriinae), a parasitoid of Stenocephus fraxini Wei (Hymenoptera, Cephidae)
Get PDFA new species of the genus Bicurta Sheng, Broad & Sun, 2012, is described and illustrated, B. hejunhuai sp. nov., from North and Northeast China. The new species was reared from the stem-sawfly Stenocephus fraxini Wei (Hymenoptera, Cephidae), which is the first host record for the genus Bicurta.This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published pdf.NHM Repositor
Global Review of Beach Debris Monitoring and Future Recommendations
Get PDFMarine debris is distributed worldwide and constitutes an increasing threat to our environment. The exponential increase in the level of plastic debris raises numerous concerns and has led to an intensification in plastic monitoring and research. However, global spatial and temporal patterns and knowledge gaps in debris distribution, both on land and at sea, are relatively poorly understood, mainly due to a lack of comprehensive data sets. Here, we critically review the quality of the available information about beach plastic debris worldwide to highlight where the most urgent actions are required and to promote the standardization of reporting metrics and sampling methods among researchers. From a total of 174 studies evaluated, 27.0% reported marine debris densities in metrics that were not comparable. Some studies failed to report basic parameters, such as the date of the sampling (9.8%) or the size of the collected debris (19.5%). Our findings show that current research regarding beach debris requires significant improvement and standardization and would benefit from the adoption of a common reporting framework to promote consensus within the scientific community.The attached document is the authors’ final accepted/submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it.NHM Repositor
MINERALOGICAL AND GEOCHEMICAL FEATURES OF SATPAEV Ti-Zr PLACER DEPOSIT, EAST KAZAKHSTAN
No full textThe data of mineralogical and geochemical studies of Ti-Zr mineral sands and heavy fraction of the
mineral concentrate of Placer No. 1 of the Satpaev deposit (East Kazakhstan) are obtained. The mineralogical
composition of the mineral sands: quartz, albite, ilmenite, and feldspar; micro-sized crystals of barite, zircon, monazite, a mineral of pyrochlore composition, were identified by electron microprobe. Crystal morphology of ore
minerals: ilmenite and zircon and chemical composition of ilmenite were determined. The development of
leucoxenization in microcracks and edges of ilmenite crystals have also been revealed.
Geochemical features of productive horizons include the apparent enrichment of light rare-earth elements
(LREE) in comparison with heavy rare-earth elements (HREE), and pronounced negative Eu anomaly that indicate
high degree of fractionation of source rocks. Granitoids of the Preobrazhensk intrusion are the likely source of the
Satpaev placer deposit.
Results of petrological and geochemical research indicate that localization of ore minerals took place during
chemical weathering, which enabled release of ore minerals of titanium and zirconium with their further redeposition in local continental coastal settings in warm and humid climate.This is an open access article, available to all readers online. The attached file is the published version of the article.NHM Repositor
Identification and functional prediction of mitochondrial complex III and IV mutations associated with glioblastoma
Get PDFBackground: Glioblastoma (GBM) is the most common primary brain tumor in adults, with a dismal prognosis. Treatment is hampered by GBM's unique biology, including differential cell response to therapy. Although several mitochondrial abnormalities have been identified, how mitochondrial DNA (mtDNA) mutations contribute to GBM biology and therapeutic response remains poorly described. We sought to determine the spectrum of functional complex III and IV mtDNA mutations in GBM. Methods: The complete mitochondrial genomes of 10 GBM cell lines were obtained using next-generation sequencing and combined with another set obtained from 32 GBM tissues. Three-dimensional structural mapping and analysis of all the nonsynonymous mutations identified in complex III and IV proteins was then performed to investigate functional importance. Results: Over 200 mutations were identified in the mtDNAs, including a significant proportion with very low mutational loads. Twenty-five were nonsynonymous mutations in complex III and IV, 9 of which were predicted to be functional and affect mitochondrial respiratory chain activity. Most of the functional candidates were GBM specific and not found in the general population, and 2 were present in the germ-line. Patient-specific maps reveal that 43% of tumors carry at least one functional candidate. Conclusions: We reveal that the spectrum of GBM-associated mtDNA mutations is wider than previously thought, as well as novel structural-functional links between specific mtDNA mutations, abnormal mitochondria, and the biology of GBM. These results could provide tangible new prognostic indicators as well as targets with which to guide the development of patient-specific mitochondrially mediated chemotherapeutic approaches.This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License
(http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium,
provided the original work is properly cited. For commercial re-use, please contact [email protected] Repositor
Multi-stage arc magma evolution recorded by apatite in volcanic rocks
Get PDFGold open access fee paid by NHMProtracted magma storage in the deep crust is a key stage in the formation of evolved, hydrous arc magmas that can result in explosive volcanism and the formation of economically valuable magmatic-hydrothermal ore deposits. High magmatic water content in the deep crust results in extensive amphibole ± garnet fractionation and the suppression of plagioclase crystallization as recorded by elevated Sr/Y ratios and high Eu (high Eu/Eu*) in the melt. Here, we use a novel approach to track the petrogenesis of arc magmas using apatite trace element chemistry in volcanic formations from the Cenozoic arc of central Chile. These rocks formed in a magmatic cycle that culminated in high-Sr/Y magmatism and porphyry ore deposit formation in the Miocene. We use Sr/Y, Eu/Eu*, and Mg in apatite to track discrete stages of arc magma evolution. We apply fractional crystallization modeling to show that early-crystallizing apatite can inherit a high-Sr/Y and high-Eu/Eu* melt chemistry signature that is predetermined by amphibole-dominated fractional crystallization in the lower crust. Our modeling shows that crystallization of the in situ host-rock mineral assemblage in the shallow crust causes competition for trace elements in the melt that leads to apatite compositions diverging from bulk-magma chemistry. Understanding this decoupling behavior is important for the use of apatite as an indicator of metallogenic fertility in arcs and for interpretation of provenance in detrital studies.© 2020 The Authors
Gold Open Access: This paper is published under the terms of the CC-BY license (https://creativecommons.org/licenses/by/4.0/).
The attached file is the published pdf.NHM Repositor
What Colour Is That Sparrow? A Case Study: Colour Aberrations In The House Sparrow Passer Domesticus
Get PDFTimes Cited: 0 0 Import from WoS only - CL not assigned grouping, NHM authors etc.In this paper 16 distinct, heritable colour aberrations (mutations) in the House Sparrow
are described, based on specimens found in museum collections, records of individuals seen in the wild and from bird breeders keeping aberrant coloured sparrows in
captivity. Based on the frequency found in the museum specimens Brown is the most
common mutation in the House Sparrow, followed by Ino and Albino. Besides the mutations there is also a, presumably, non-heritable aberration called Progressive Greying
described. Progressive Greying is in fact by far the most common colour aberration
found in the species but was, in the past, always assigned as ‘Partial Albino’ without
its real nature being understood. This paper will give some insight in the nature of
Progressive Greying.This journal is a pure open access journal and is published under a Creative Commons Attribution (CC BY) license.NHM Repositor
Aram Dorsum: An Extensive Mid‐Noachian Age Fluvial Depositional System in Arabia Terra, Mars
Get PDFA major debate in Mars science is the nature of the early Mars climate, and the availability ofprecipitation and runoff. Observations of relict erosional valley networks have been proposed as evidencefor extensive surface runoff around the Noachian‐Hesperian boundary. However, these valley networks onlyprovide a time‐integrated record of landscape evolution, and thus, the timing, relative timescales andintensity of aqueous activity required to erode the valleys remain unknown. Here, we investigate an ancientfluvial sedimentary system in western Arabia Terra, now preserved in positive relief. This ridge, “AramDorsum,” is flat‐topped, branching, ~85 km long, and particularly well preserved. We show that AramDorsum was an aggradational alluvial system and that the existing ridge was once a large river channel beltset in extensive flood plains, many of which are still preserved. Smaller, palaeochannel belts feed themain system; their setting and network pattern suggest a distributed source of water. The alluvial successionis up to 60 m thick, suggesting a formation time of 105to 107years by analogy to Earth. Our observationsare consistent with Aram Dorsum having formed by long‐lived flows of water, sourced both locally, andregionally as part of a wider alluvial system in Arabia Terra. This suggests frequent or seasonal precipitationas the source of water. Correlating our observations with previous regional‐scale mapping shows thatAram Dorsum formed in the mid‐Noachian. Aram Dorsum is one of the oldest fluvial systems described onMars and indicates climatic conditions that sustained surface river flows on early Mars.©2020. The Authors.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. The attached file is the published pdf.NHM Repositor
Anglers’ Riverfly Monitoring Initiative (ARMI): A UK-wide citizen science project for water quality assessment
Get PDFThe Anglers’ Riverfly Monitoring Initiative (ARMI) is a UK-wide citizen science project focused on river water quality assessment. There are currently >2000 ARMI volunteers monitoring >1600 sites that are organized into 35 regional hubs across the UK. ARMI is effective in the early detection of water pollution and complements the routine monitoring undertaken by the UK statutory environment agencies. ARMI volunteers are trained to take standardized 3-min kick-samples of freshwater invertebrates from a river site, and use these samples to produce an ARMI score based on the abundance of key pollution-sensitive taxa. ARMI scores and standard invertebrate monitoring metrics are closely correlated. Each sampling site has a ‘trigger level’ score set by the national regulatory authority—e.g., the Environment Agency (EA) in England. If the ARMI score falls below this trigger level, the regulatory authority is notified and agency officers investigate the cause of the low score. This process has resulted in many reports of pollution incidents that otherwise may have gone undiscovered but were instead rapidly detected and neutralized. In some cases, investigations resulted in fines being levied against those responsible. ARMI data have also proved useful in assessing the effectiveness of river restoration schemes. Here, we demonstrate the effectiveness of the ARMI as a structured citizen science program in enhancing the environmental protection of rivers. We also show that the ARMI program complements the work of statutory authorities and describe how it promotes community engagement with river environments.© 2019 by The Society for Freshwater Science. The attached file is the published pdf (embargo period has expired).NHM Repositor
Quantifying the Effect of Anthropogenic Climate Change on Calcifying Plankton
Get PDFWidely regarded as an imminent threat to our oceans, ocean acidification has been documented in all oceanic basins. Projected changes in seawater chemistry will have catastrophic biotic effects due to ocean acidification hindering biogenic carbonate production, which will in turn lead to substantial changes in marine ecosystems. However, previous attempts to quantify the effect of acidification on planktonic calcifying organisms has relied on laboratory based studies with substantial methodological limitations. This has been overcome by comparing historic plankton tows from the seminal HMS Challenger Expedition (1872–1876) with the recent Tara Oceans expedition material (2009–2016). Nano CT-scans of selected equatorial Pacific Ocean planktonic foraminifera, have revealed that all modern specimens had up to 76% thinner shells than their historic counterparts. The “Challenger Revisited” project highlights the potential of historic ocean collections as a tool to investigate ocean acidification since the early Industrial Revolution. Further analyses of such biotic archives will enable researchers to quantify the effects of anthropogenic climate change across the globe.Open Access This article is licensed under a Creative Commons Attribution 4.0 International
License, which permits use, sharing, adaptation, distribution and reproduction in any medium or
format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Te images or other third party material in this
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copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
© Te Author(s) 2020
The attached article is the published pdf.NHM Repositor