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https://www.readbyqxmd.com/read/27894994/a-new-genus-of-anostomidae-ostariophysi-characiformes-diversity-phylogeny-and-biogeography-based-on-cytogenetic-molecular-and-morphological-data
#1
Jorge L Ramirez, José L O Birindelli, Pedro M Galetti
A new genus of Anostomidae (Characiformes) is described to include ten valid extant species previously classified in Leporinus or Hypomasticus and distributed throughout most major river basins in South America: L. brinco, L. conirostris, L. elongatus, H. garmani, L. macrocephalus, L. muyscorum, L. obtusidens, L. piavussu, L. reinhardti, and L. trifasciatus. The monophyly of Megaleporinus is well-supported in a phylogenetic analysis based on two mitochondrial and three nuclear genes, as well as its sister group relationship to Abramites...
November 25, 2016: Molecular Phylogenetics and Evolution
https://www.readbyqxmd.com/read/27884104/phylogeography-reveals-an-ancient-cryptic-radiation-in-east-asian-tree-frogs-hyla-japonica-group-and-complex-relationships-between-continental-and-island-lineages
#2
Christophe Dufresnes, Spartak N Litvinchuk, Amaël Borzée, Yikweon Jang, Jia-Tang Li, Ikuo Miura, Nicolas Perrin, Matthias Stöck
BACKGROUND: In contrast to the Western Palearctic and Nearctic biogeographic regions, the phylogeography of Eastern-Palearctic terrestrial vertebrates has received relatively little attention. In East Asia, tectonic events, along with Pleistocene climatic conditions, likely affected species distribution and diversity, especially through their impact on sea levels and the consequent opening and closing of land-bridges between Eurasia and the Japanese Archipelago. To better understand these effects, we sequenced mitochondrial and nuclear markers to determine phylogeographic patterns in East-Asian tree frogs, with a particular focus on the widespread H...
November 23, 2016: BMC Evolutionary Biology
https://www.readbyqxmd.com/read/27878213/holocene-paleo-sea-level-changes-along-the-coast-of-rio-de-janeiro-southern-brazil-comment-on-castro-et-al-2014
#3
Rodolfo J Angulo, Paulo C F Giannini, Maria Cristina DE Souza, Guilherme C Lessa
The present work discusses and reinterprets paleo-sea level indicators used to build Holocene sea-level curve for the coast of Rio de Janeiro at former works. We conclude that: (a) the paleo-sea levels inferred by vermetid remains show that sea-level has fallen over the past 4400 years, at least; (b) the paleo-sea level inferred by the beachrock facies and dated shells of Jaconé shows that sea-level was near the present elevation between 8198 and 5786 years before present; and (c) several shells from other beachrocks were deposited probably thousands of years after the specimens died and consequently do not allow precise reconstructions of paleo-sea levels...
November 10, 2016: Anais da Academia Brasileira de Ciências
https://www.readbyqxmd.com/read/27875538/seasonal-cyclicity-in-trace-elements-and-stable-isotopes-of-modern-horse-enamel
#4
Niels J de Winter, Christophe Snoeck, Philippe Claeys
The study of stable isotopes in fossil bioapatite has yielded useful results and has shown that bioapatites are able to faithfully record paleo-environmental and paleo-climatic parameters from archeological to geological timescales. In an effort to establish new proxies for the study of bioapatites, intra-tooth records of enamel carbonate stable isotope ratios from a modern horse are compared with trace element profiles measured using laboratory micro X-Ray Fluorescence scanning. Using known patterns of tooth eruption and the relationship between stable oxygen isotopes and local temperature seasonality, an age model is constructed that links records from six cheek upper right teeth from the second premolar to the third molar...
2016: PloS One
https://www.readbyqxmd.com/read/27824887/the-bacteriohopanepolyol-inventory-of-novel-aerobic-methane-oxidising-bacteria-reveals-new-biomarker-signatures-of-aerobic-methanotrophy-in-marine-systems
#5
Darci Rush, Kate A Osborne, Daniel Birgel, Andreas Kappler, Hisako Hirayama, Jörn Peckmann, Simon W Poulton, Julia C Nickel, Kai Mangelsdorf, Marina Kalyuzhnaya, Frances R Sidgwick, Helen M Talbot
Aerobic methane oxidation (AMO) is one of the primary biologic pathways regulating the amount of methane (CH4) released into the environment. AMO acts as a sink of CH4, converting it into carbon dioxide before it reaches the atmosphere. It is of interest for (paleo)climate and carbon cycling studies to identify lipid biomarkers that can be used to trace AMO events, especially at times when the role of methane in the carbon cycle was more pronounced than today. AMO bacteria are known to synthesise bacteriohopanepolyol (BHP) lipids...
2016: PloS One
https://www.readbyqxmd.com/read/27824339/dna-evidence-of-bowhead-whale-exploitation-by-greenlandic-paleo-inuit-4-000-years-ago
#6
Frederik Valeur Seersholm, Mikkel Winther Pedersen, Martin Jensen Søe, Hussein Shokry, Sarah Siu Tze Mak, Anthony Ruter, Maanasa Raghavan, William Fitzhugh, Kurt H Kjær, Eske Willerslev, Morten Meldgaard, Christian M O Kapel, Anders Johannes Hansen
The demographic history of Greenland is characterized by recurrent migrations and extinctions since the first humans arrived 4,500 years ago. Our current understanding of these extinct cultures relies primarily on preserved fossils found in their archaeological deposits, which hold valuable information on past subsistence practices. However, some exploited taxa, though economically important, comprise only a small fraction of these sub-fossil assemblages. Here we reconstruct a comprehensive record of past subsistence economies in Greenland by sequencing ancient DNA from four well-described midden deposits...
November 8, 2016: Nature Communications
https://www.readbyqxmd.com/read/27797199/uranium-isotope-fractionation-during-adsorption-co-precipitation-and-biotic-reduction
#7
Duc Huy Dang, Breda Novotnik, Wei Wang, R Bastian Georg, Robert Douglas Evans
Uranium contamination of surface environments is a problem associated with both U-ore extraction/processing and situations in which groundwater comes into contact with geological formations high in uranium. Apart from the environmental concerns about U contamination, its accumulation and isotope composition have been used in marine sediments as a paleo-proxy of the Earth' oxygenation history. Understanding U isotope geochemistry is then essential either to develop sustainable remediation procedures as well as for use in paleo-tracer applications...
October 31, 2016: Environmental Science & Technology
https://www.readbyqxmd.com/read/27779217/responses-of-the-summer-asian-pacific-zonal-thermal-contrast-and-the-associated-evolution-of-atmospheric-circulation-to-transient-orbital-changes-during-the-holocene
#8
Dong Xiao, Ping Zhao, Yue Wang, Xiuji Zhou
This study investigates the response of large-scale atmospheric circulation over the Asian-Pacific sector and precipitation over eastern China to transient orbital changes during the Holocene summer using an intermediate-complexity climate model. Corresponding to variations in the incoming solar radiation, the eddy sea level pressure (SLP) exhibited an out-of-phase relationship between the North Pacific and the Eurasian landmass that was similar to the present-day Asia-Pacific Oscillation (APO) pattern and was defined as the paleo-APO...
October 25, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27768316/the-two-alternative-rate-determining-steps-in-benzylic-lithiation-reactions-of-esters-and-carbamates
#9
Fernando Fernández-Nieto, M Rita Paleo, Roberto Colunga, M Luz Raposo, Luis Garcia-Rio, F Javier Sardina
Lithiation reactions of tertiary benzylic esters and carbamates have been studied. Kinetic methodology revealed that a two-step reaction pathway should be considered for these reactions, where either the lithium precomplexation and/or the proton transfer steps can be rate determining. Kinetic isotopic effects were evaluated by comparison of the lithiations of the corresponding protio/deutero substrates, and the results obtained support the notion that lithium precomplexation is taking place on the reaction pathway and that it is the rate-determining step in this transformation...
October 21, 2016: Organic Letters
https://www.readbyqxmd.com/read/27766703/a-simple-and-reliable-anion-exchange-resin-method-for-sulfate-extraction-and-purification-suitable-for-multiple-o-and-s-isotope-measurements
#10
Erwann Le Gendre, Erwan Martin, Benoit Villemant, Pierre Cartigny, Nelly Assayag
RATIONALE: The O- and S- isotope compositions of sulfates can be used as key tracers of the fate and sink of sulfate in both terrestrial and extra-terrestrial environments. However, their application remains limited in those geological systems where sulfate occurs in low concentrations. Here we present a simple and reliable method to extract, purify and concentrate sulfate from natural samples. The method allows us to take into account the separation of nitrate, which is known to be an issue in O-isotope analysis...
October 21, 2016: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/27753214/how-to-make-stone-soup-is-the-paleo-diet-a-missed-opportunity-for-anthropologists
#11
Melanie L Chang, April Nowell
For the past few years, people everywhere have been "going Paleo." Websites and social media touting the benefits of eating a "Paleo diet" and following a "Paleolithic life style" serve as calls to arms for health-conscious individuals seeking information about the latest health and fitness trends. Many of these people participate in programs such as Crossfit, which involve major social and life-style modification components and therefore facilitate the dissemination of dietary fads.(1) The PALEOf(x)(TM) conference, which bills itself as "the world's premier holistic wellness event," has attracted sellout crowds of thousands of attendees for the last four years...
September 2016: Evolutionary Anthropology
https://www.readbyqxmd.com/read/27726759/human-lice-in-paleoentomology-and-paleomicrobiology
#12
Didier Raoult, Rezak Drali, Kosta Mumcuoglu
Lice are a classic example of cospeciation. Human lice confirm this cospeciation with lice specialized in hominids which differ from those of gorillas and chimpanzees. Head lice and body lice seem to belong to closely related species with different ecotypes and a different geographical distribution which may reflect population movements. Paleo-entomology allows us in some cases to trace the migrations of archaic human populations. The analysis of lice found on mummies in Egypt and South America has clarified a certain number of these migrations, also the study of lice and the diseases they transmit has shed a new light on the epidemics of the past...
August 2016: Microbiology Spectrum
https://www.readbyqxmd.com/read/27677769/erosion-and-sedimentation-during-the-september-2015-flooding-of-the-kinu-river-central-japan
#13
Dan Matsumoto, Yuki Sawai, Masaki Yamada, Yuichi Namegaya, Tetsuya Shinozaki, Daisuke Takeda, Shigehiro Fujino, Koichiro Tanigawa, Atsunori Nakamura, Jessica E Pilarczyk
Erosional and sedimentary features associated with flooding have been documented in both modern and past cases. However, only a few studies have demonstrated the relationship between these features and the corresponding hydraulic conditions that produced them, making it difficult to evaluate the magnitude of paleo-flooding. This study describes the characteristics associated with inundation depth and flow direction, as well as the erosional and sedimentary features resulting from the disastrous flooding of the Kinu River, central Japan, in September 2015...
September 28, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27671620/historical-colonization-and-dispersal-limitation-supplement-climate-and-topography-in-shaping-species-richness-of-african-lizards-reptilia-agaminae
#14
W Daniel Kissling, Anne Blach-Overgaard, Roelof E Zwaan, Philipp Wagner
To what extent deep-time dispersal limitation shapes present-day biodiversity at broad spatial scales remains elusive. Here, we compiled a continental dataset on the distributions of African lizard species in the reptile subfamily Agaminae (a relatively young, Neogene radiation of agamid lizards which ancestors colonized Africa from the Arabian peninsula) and tested to what extent historical colonization and dispersal limitation (i.e. accessibility from areas of geographic origin) can explain present-day species richness relative to current climate, topography, and climate change since the late Miocene (~10 mya), the Pliocene (~3 mya), and the Last Glacial Maximum (LGM, 0...
September 27, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27667100/morphology-controls-on-calcite-recrystallization
#15
Frank Heberling, Leonie Paulig, Zhe Nie, Dieter Schild, Nicolas Finck
Environmental scientists and geoscientists working in different fields regard the reactivity of calcite and corresponding changes in its trace elemental- or isotopic composition from diametrically opposed points of view. As one extreme, calcite based environmental remediation strategies rely on the fast recrystallization of calcite and the concurrent uptake and immobilization of pollutants. Paleo-ecological investigations denote the other extreme, and rely on the invariability of calcite composition over geological periods of time...
October 10, 2016: Environmental Science & Technology
https://www.readbyqxmd.com/read/27621451/twenty-million-year-relationship-between-mammalian-diversity-and-primary-productivity
#16
Susanne A Fritz, Jussi T Eronen, Jan Schnitzler, Christian Hof, Christine M Janis, Andreas Mulch, Katrin Böhning-Gaese, Catherine H Graham
At global and regional scales, primary productivity strongly correlates with richness patterns of extant animals across space, suggesting that resource availability and climatic conditions drive patterns of diversity. However, the existence and consistency of such diversity-productivity relationships through geological history is unclear. Here we provide a comprehensive quantitative test of the diversity-productivity relationship for terrestrial large mammals through time across broad temporal and spatial scales...
September 27, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27613240/phylogeography-of-diptychus-maculatus-cyprinidae-endemic-to-the-northern-margin-of-the-qtp-and-tien-shan-region
#17
Guogang Li, Yongtao Tang, Renyi Zhang, Kai Zhao
BACKGROUND: Phylogeography and historical demography of the cyprinid fish Diptychus maculatus (subfamily Schizothoracinae) are evaluated across three river systems in the Northern Qinghai-Tibetan Plateau (QTP) and Tien Shan range: the Indus River, Tarim River and Ili River. RESULTS: Results from both mtDNA (16S rRNA, Cyt b and D-loop) and nucDNA (RAG-2) resolved four reciprocally monophyletic clades, representing populations from Indus River, South Tarim River, North Tarim River and Ili River, respectively...
2016: BMC Evolutionary Biology
https://www.readbyqxmd.com/read/27613199/inconsistencies-between-14-c-and-short-lived-radionuclides-based-sediment-accumulation-rates-effects-of-long-term-remineralization
#18
M Baskaran, T S Bianchi, T R Filley
(14)C is the most widely utilized geochronometer to investigate geological, geochemical and geophysical problems over the past 5 decades. Establishment of precise sedimentation rates is crucial for the reconstruction of paleo-climate, -ecological and - environmental studies when extrapolation of sedimentation rates is utilized for time scales beyond the dating range. However, agreement between short-term and long-term sedimentation rates in anthropogenically unperturbed sediment cores has not been shown. Here we show that the AMS (14)C-based long-term mass accumulation rate (MAR) of an organic-rich (>70%) sediment core from Mud Lake, Florida to be ∼5 times lower than the short-term MAR obtained using (239,240)Pu, (137)Cs and excess (210)Pb ((210)Pbxs)...
September 6, 2016: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/27587984/erosion-rate-study-at-the-allchar-deposit-macedonia-based-on-radioactive-and-stable-cosmogenic-nuclides-26-al-36-cl-3-he-and-21-ne
#19
M K Pavićević, V Cvetković, S Niedermann, V Pejović, G Amthauer, B Boev, F Bosch, I Aničin, W F Henning
This paper focuses on constraining the erosion rate in the area of the Allchar Sb-As-Tl-Au deposit (Macedonia). It contains the largest known reserves of lorandite (TlAsS2), which is essential for the LORanditeEXperiment (LOREX), aimed at determining the long-term solar neutrino flux. Because the erosion history of the Allchar area is crucial for the success of LOREX, we applied terrestrial in situ cosmogenic nuclides including both radioactive ((26)Al and (36)Cl) and stable ((3)He and (21)Ne) nuclides in quartz, dolomite/calcite, sanidine, and diopside...
February 2016: Geochemistry, Geophysics, Geosystems: G³
https://www.readbyqxmd.com/read/27538751/evaporative-concentration-of-arsenic-in-groundwater-health-and-environmental-implications-la-laguna-region-mexico
#20
Adrián Ortega-Guerrero
High arsenic concentrations in groundwater have been documented in La Laguna Region (LLR) in arid northern Mexico, where arsenic poisoning is both chronic and endemic. A heated debate has continued for decades on its origin. LLR consisted of a series of ancient connected lakes that developed at the end of a topographic depression under closed basin conditions. This study addresses the isotopic, chemical composition of the groundwater and geochemical modeling in the southeasternmost part of the LLR to determine the origin of arsenic...
August 18, 2016: Environmental Geochemistry and Health
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