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Li Z.,Beijing Museum of Natural History | Wang N.,Chinese Academy of Agricultural Sciences | Yang D.,China Agricultural University
Zootaxa | Year: 2014

The species of the genus Hybos Meigen from Northwest China are reviewed. The following five species are described as new to science: Hybos elongatus sp. nov., H. flavitibialis sp. nov., H. projectus sp. nov., H. qinlingensis sp. nov., and H. xii sp. nov. A key to the 17 species of the genus Hybos from Northwest China is provided. Copyright © 2014 Magnolia Press.


Longrich N.R.,Yale University | Vinther J.,University of Texas at Austin | Vinther J.,University of Bristol | Meng Q.,Beijing Museum of Natural History | And 2 more authors.
Current Biology | Year: 2012

In modern birds (Neornithes), the wing is composed of a layer of long, asymmetrical flight feathers overlain by short covert feathers [1-3]. It has generally been assumed that wing feathers in the Jurassic bird Archaeopteryx [4-9] and Cretaceous feathered dinosaurs [10, 11] had the same arrangement. Here, we redescribe the wings of the archaic bird Archaeopteryx lithographica [3-5] and the dinosaur Anchiornis huxleyi [12, 13] and show that their wings differ from those of Neornithes in being composed of multiple layers of feathers. In Archaeopteryx, primaries are overlapped by long dorsal and ventral coverts. Anchiornis has a similar configuration but is more primitive in having short, slender, symmetrical remiges. Archaeopteryx and Anchiornis therefore appear to represent early experiments in the evolution of the wing. This primitive configuration has important functional implications: although the slender feather shafts of Archaeopteryx [14] and Anchiornis [12] make individual feathers weak, layering of the wing feathers may have produced a strong airfoil. Furthermore, the layered arrangement may have prevented the feathers from forming a slotted tip or separating to reduce drag on the upstroke. The wings of early birds therefore may have lacked the range of functions seen in Neornithes, limiting their flight ability. © 2012 Elsevier Ltd.


Wei X.,Northwest University, China | Shao M.,Northwest University, China | Gale W.J.,Northwest University, China | Zhang X.,Northwest University, China | Li L.,Beijing Museum of Natural History
Soil Biology and Biochemistry | Year: 2013

The conversion of natural forest to cropland generally results in the loss of soil organic carbon (OC) and an increase in CO2 flux to the atmosphere. The dynamics of aggregate-associated OC after conversion to cropland are still not well understood. Such an understanding is essential for accurately estimating C flux between soil and the atmosphere. To learn more about OC dynamics after cultivation of natural forest land, we measured total soil and aggregate-associated OC in paired forest and cropland plots in Shaanxi Province, China. The cropland had been converted from adjacent forest 4, 50, and 100 yrs previously. As expected, the conversion to cropland resulted in significant declines in total soil OC concentrations and stocks. The largest decreases occurred during the early stages of cultivation. A century of cultivation decreased total soil OC stocks in the 0-20 cm depth by 0.77 kg m-2. Macroaggregate-associated OC stocks decreased, but microaggregate-associated OC stocks increased following the conversion of forest to cropland. Silt + clay-associated OC stocks were not affected. The reduction in macroaggregate-associated OC stocks was caused by declines in both the amount of soil in the macroaggregate fraction and by decreases in the concentration of macroaggregate-associated OC. The results of this study indicate the conversion of forest to cropland not only reduced total soil OC stocks, but also caused a percentage shift in the distribution of total soil OC among aggregate size classes and among soil depths. These shifts would delay the loss of OC, so the loss of OC in forest soil due to cultivation might thus be lower than expected. © 2012 Elsevier Ltd.


Tong H.,30 rue Carnot | Zhang J.-Y.,CAS Institute of Vertebrate Paleontology and Paleoanthropology | Li J.-J.,Beijing Museum of Natural History
Neues Jahrbuch fur Geologie und Palaontologie - Abhandlungen | Year: 2010

Anosteira is a carettochelytid turtle known from the Eocene of Asia and North America and includes several species. The species A. maomingensis CHOW & LIU, 1953 was established originally on the basis of two internal molds. The present study is based on new specimens collected by the IVPP in Maoming during 2005-2006 and unpublished specimens housed in the Beijing Museum of Natural History, which include more than twenty shells and a lower jaw. A. maomingensis is characterized by its large size, absence of all marginal scutes and reduced pleural scutes, which do not cover the lateral part of the costal plates. The lower jaw has a wide, posteriorly expanded and concave triturating surface, a strong and tall coronoid process lying on the middle of the jaw ramus and deeply excavated lateral surface under the coronoid process. © 2010 Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.


Wang M.,CAS Institute of Vertebrate Paleontology and Paleoanthropology | Liu D.,Beijing Museum of Natural History
Journal of Systematic Palaeontology | Year: 2015

A complete redescription of Cathayornis caudatus Hou, 1997 is provided based on new information from a resin cast of the holotype, leading to reinterpretation of many morphological features of this initially poorly diagnosed taxon. Detailed comparisons across various specimens referred to Cathayornithidae Zhou et al., 1992 indicate that Sinornis santensis, Cathayornis yandica, C. caudatus and Eocathayornis walkeri are valid taxa, but that C. chabuensis should be regarded as a nomen dubium. The holotype and referred specimens of C. chabuensis differ significantly in morphology, indicating that they do not belong to the same species. A comprehensive phylogenetic analysis targeted at Mesozoic birds reveals that neither Cathayornithidae Zhou et al., 1992 nor Cathayornis Zhou et al., 1992 are monophyletic, and that C. yandica can be regarded as the only species in a monospecific Cathayornithidae. The holotype of ‘C. caudatus’ is assigned to the genus Houornis gen. nov., and a taxonomic reassessment of other ‘cathayornithids’ is presented.http://zoobank.org/urn:lsid:zoobank.org:pub:0B1A404A-CC6A-4609-8CC5-C0DD62983C9A © The Trustees of the Natural History Museum, London 2015. All Rights Reserved.


Luo Z.-X.,University of Chicago | Meng Q.-J.,Beijing Museum of Natural History | Ji Q.,Chinese Academy of Geological Sciences | Liu D.,Beijing Museum of Natural History | And 2 more authors.
Science | Year: 2015

A new Late Jurassic docodontan shows specializations for a subterranean lifestyle. It is similar to extant subterranean golden moles in having reduced digit segments as compared to the ancestral phalangeal pattern of mammaliaforms and extant mammals. The reduction of digit segments can occur in mammals by fusion of the proximal and intermediate phalangeal precursors, a developmental process for which a gene and signaling network have been characterized in mouse and human. Docodontans show a positional shift of thoracolumbar ribs, a developmental variation that is controlled by Hox9 and Myf5 genes in extant mammals. We argue that these morphogenetic mechanisms of modern mammals were operating before the rise of modern mammals, driving the morphological disparity in the earliest mammaliaform diversification. © 2015, American Association for the Advancement of Science. All rights reserved.


Meng Q.-J.,Beijing Museum of Natural History | Ji Q.,Chinese Academy of Geological Sciences | Zhang Y.-G.,Beijing Museum of Natural History | Liu D.,Beijing Museum of Natural History | And 2 more authors.
Science | Year: 2015

A new docodontan mammaliaform from the Middle Jurassic of China has skeletal features for climbing and dental characters indicative of an omnivorous diet that included plant sap. This fossil expands the range of known locomotor adaptations in docodontans to include climbing, in addition to digging and swimming. It further shows that some docodontans had a diet with a substantial herbivorous component, distinctive from the faunivorous diets previously reported in other members of this clade. This reveals a greater ecological diversity in an early mammaliaform clade at a more fundamental taxonomic level not only between major clades as previously thought. © 2015, American Association for the Advancement of Science. All rights reserved.


Zhang Z.,Geological Museum of China | Schneider J.W.,TU Bergakademie Freiberg | Hong Y.,Beijing Museum of Natural History
Journal of Systematic Palaeontology | Year: 2013

The most ancient known roach, Qilianiblatta namurensis gen. et sp. nov. from the earliest Pennsylvanian (Namurian B/C) Qilianshan entomofauna, is described from material excavated in the Qilianshan Mountains of north-western China. The new genus is characterized by a mosaic of plesiomorphic and apomorphic features typical of various Euramerican and Angaran Late Palaeozoic blattid genera. Despite a limited time gap between the age of Q. namurensis and that of the previously known oldest blattids (archimylacrids of Westphalian A age, 1-2 Ma younger), the pattern of main veins and cross venation of Q. namurensis appears in some regards more advanced. This is particularly apparent in the only weakly expressed primary dichotomy of main veins and the relatively modern aspect of the cross venation. The new taxon raises questions regarding the polyphyletic origin of the 'phyloblattoid' groundplan, namely once in the Euramerican biotic province at the end of the Westphalian and stemming from archimylacrids, and earlier in the Cathaysian (-Angaran?) biotic province from forms like Qilianiblatta. Forewings of Q. namurensis are clearly protective wings (tegmina) and probably were not involved directly in the production of lift during flight. These wings are considerably advanced relative to the earliest diversification of the winged insects and the general groundplan for hexapodan wings. It is possible that winged blattids appeared as early as the Devonian. © 2013 Natural History Museum.


Huang M.-R.,Beijing Museum of Natural History
Acta Oecologica | Year: 2010

Based on herbarium collections, the altitudinal distribution patterns of six species of the lichen genus Stereocaulon in China were analyzed. Species are elevation-dependent: normal distributions and corresponding empirical formulae were detected for the genus and S. japonicum and S. paschale, the species distributed in low elevation areas, and log-normal distributions detected for S. sorediiferum and S. tomentosum, the species in medium elevation areas, while S. pomiferum and S. myriocarpum, the species in high elevation areas, appear to be irregularly distributed according to altitude. Such formulae should prove valuable for biological conservation practices. © 2009 Elsevier Masson SAS. All rights reserved.


Wei X.,Northwest University, China | Shao M.,Northwest University, China | Gale W.,Shihezi University | Li L.,Beijing Museum of Natural History
Scientific Reports | Year: 2014

Several reviews have analyzed the factors that affect the change in soil organic C (SOC) when forest is converted to agricultural land; however, the effects of forest type and cultivation stage on these changes have generally been overlooked. We collated observations from 453 paired or chronosequential sites where forests have been converted to agricultural land and then assessed the effects of forest type, cultivation stage, climate factors, and soil properties on the change in the SOC stock and the SOC turnover rate constant (k). The percent decrease in SOC stocks and the turnover rate constants both varied significantly according to forest type and cultivation stage. The largest decrease in SOC stocks was observed in temperate regions (52% decrease), followed by tropical regions (41% decrease) and boreal regions (31% decrease). Climate and soil factors affected the decrease in SOC stocks. The SOC turnover rate constant after the conversion of forests to agricultural land increased with the mean annual precipitation and temperature. To our knowledge, this is the first time that original forest type was considered when evaluating changes in SOC after being converted to agricultural land. The differences between forest types should be considered when calculating global changes in SOC stocks.

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