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Inference of phylogenetic relationships among key angiosperm lineages using a compatibility method on a molecular data set 被引量:5
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作者 George F.ESTABROOK 《植物分类学报》 CSCD 北大核心 2008年第2期130-141,共12页
Phylogenetic relationships among the five key angiosperm lineages, Ceratophyllum, Chloranthaceae, eudicots, magnoliids, and monocots, have resisted resolution despite several large-scale analyses sampling taxa and cha... Phylogenetic relationships among the five key angiosperm lineages, Ceratophyllum, Chloranthaceae, eudicots, magnoliids, and monocots, have resisted resolution despite several large-scale analyses sampling taxa and characters extensively and using various analytical methods. Meanwhile, compatibility methods, which were explored together with parsimony and likelihood methods during the early development stage of phylogenetics, have been greatly under-appreciated and not been used to analyze the massive amount of sequence data to recon-struct the basal angiosperm phylogeny. In this study, we used a compatibility method on a data set of eight genes (mitochondrial atp1, matR, and nad5, plastid atpB, matK, rbcL, and rpoC2, and nuclear 18S rDNA) gathered in an earlier study. We selected two sets of characters that are compatible with more of the other characters than a random character would be with at probabilities of pM<0.1 and pM<0.5 respectively. The resulting data matrices were subjected to parsimony and likelihood bootstrap analyses. Our unrooted parsimony analyses showed that Cerato-phyllum was immediately related to eudicots, this larger lineage was immediately related to magnoliids, and monocots were closely related to Chloranthaceae. All these relationships received 76%–96% bootstrap support. A likelihood analysis of the 8 gene pM<0.5 compatible site matrix recovered the same topology but with low support. Likelihood analyses of other compatible site matrices produced different topologies that were all weakly sup-ported. The topology reconstructed in the parsimony analyses agrees with the one recovered in the previous study using both parsimony and likelihood methods when no character was eliminated. Parts of this topology have also been recovered in several earlier studies. Hence, this topology plausibly reflects the true relationships among the five key angiosperm lineages. 展开更多
关键词 系统发育 被子植物 形态特征 数据库
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Tracing Patterns of Evolution through the Tree of Life: Introduction
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作者 Michael J. Donoghue 《植物分类学报》 CSCD 北大核心 2008年第3期237-238,共2页
One and half centuries ago, Charles Darwin (1859) presented overwhelming evidence and argued that all life on the earth shared common descent, and "from so simple a beginning endless forms most beautiful and most... One and half centuries ago, Charles Darwin (1859) presented overwhelming evidence and argued that all life on the earth shared common descent, and "from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved". Ernst Haeckel (1886) 展开更多
关键词 达尔文 进化论 物种 血统
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Assessments of Biodiversity Based on Molecular Markers and Morphological Traits among West-Bank, Palestine Fig Genotypes (Ficus carica L.)
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作者 Rezq Basheer-Salimia Murad Awad Joy Ward 《American Journal of Plant Sciences》 2012年第9期1241-1251,共11页
Both morphological characters and PCR-based RAPD approaches were used to determine the genetic diversity and relatedness among nine fig genotypes grown at the northern region of the West-Bank, Palestine. Although we t... Both morphological characters and PCR-based RAPD approaches were used to determine the genetic diversity and relatedness among nine fig genotypes grown at the northern region of the West-Bank, Palestine. Although we tested 28 primers for the RAPD technique, only 9 produced reasonable amplification products. A total of 57 DNA loci were detected in which 70.2% were polymorphic. DNA fragments presented a minimum of 3 and a maximum of 9 polymorphic bands using primers OPT-10 and OPA-18, respectively. Primers exhibited collective resolving power values (Rp) of 18.826. The Mwazi genotype showed the highest genetic distances among all of the other genotypes. Morphologically, considerable variations were found using 41 quantitative and qualitative traits. Adloni could be a very promising genotype for fresh consumption due to its very late maturation period, extended harvesting period, variable fruit size, and easy skin peeling. In addition, 7 genotypes presented firm fruits, which are a very important criterion for exporting purposes. Dendrogram constructed by UPGMA based on RAPD banding patterns appear somewhat contradictory to the morphological descriptors particularly with Swadi and Biadi genotypes (closed genetically and distanced morphologically), which might be attributed to the phenotypic modifications caused by environmental differences across regions. These preliminary results will make a fundamental contribution to further genetic improvement of fig crops for the region. 展开更多
关键词 Cluster Analysis FICUS CARICA L. Genetic Variability Random Amplified POLYMORPHIC DNA Morphological DESCRIPTORS
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海南岛鸟类新记录———仓鸮
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作者 梁斌 林贵生 +6 位作者 黎玉琳 杨凡 韩远军 陈宗波 李波 周润邦 王宁 《四川动物》 北大核心 2019年第1期108-109,共2页
总结近年海南岛野生鸟类救助信息系统以及海南省林业部门的相关救助记录,发现2016年10月24日-2018年7月18日,海南省三亚市及乐东县有多达10条有效的“白脸猴面鹰”记录(表1),其中8条有照片(图1:A、B)。经查阅文献(杨岚,1995),比对存放... 总结近年海南岛野生鸟类救助信息系统以及海南省林业部门的相关救助记录,发现2016年10月24日-2018年7月18日,海南省三亚市及乐东县有多达10条有效的“白脸猴面鹰”记录(表1),其中8条有照片(图1:A、B)。经查阅文献(杨岚,1995),比对存放于国内主要几所博物馆的相关鸟类标本,确认这些“白脸猴面鹰”为草鸮 科Tytonidae草鸮 属Tyto仓鸮 Tyto alba。 展开更多
关键词 野生鸟类 海南岛 林业部门 信息系统 鸟类标本 海南省 乐东县 三亚市
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New Records of Marine Macroalgae on the Caribbean on Coast of Costa Rica
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作者 Rubén Cabrera Jhoana Díaz-Larrea Schery Umanzor 《American Journal of Plant Sciences》 2019年第10期1708-1728,共21页
The results obtained in this study highlight that further the macroalgae diversity in this region is even higher than what is reported to date. Here we present eight new records of marine macroalgae collected from the... The results obtained in this study highlight that further the macroalgae diversity in this region is even higher than what is reported to date. Here we present eight new records of marine macroalgae collected from the Caribbean coast of Costa Rica between March 2011 and May 2019. The morphological characteristics of Bryocladia cuspidata, Ceratodictyon variabile, Gracilaria hayi, Padina boergesenii, Zonaria tournefortii, Sargassum furcatum, Chaetomorpha aerea, and Bryopsis pennata var. secunda are described. The genera Bryocladia and Zonaria are reported for the first time for this region. 展开更多
关键词 NEW RECORDS Caribbean SEA Costa Rica
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The development of policy approaches for reducing nitro-gen pollution to coastal waters of the USA 被引量:3
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作者 Robert W.Howarth 《Science China(Life Sciences)》 SCIE CAS 2005年第z2期791-806,共16页
Two-thirds of the coastal rivers and bays in the United States are degraded from nutrient pollution, and nitrogen inputs these waters continue to increase. The nitrogen comes from a variety of sources, including runof... Two-thirds of the coastal rivers and bays in the United States are degraded from nutrient pollution, and nitrogen inputs these waters continue to increase. The nitrogen comes from a variety of sources, including runoff from agricultural fields, concentrated animal feeding operations, atmospheric deposition from fossil fuel combustion, and sewage and septic wastes.Technical solutions for nitrogen pollution exist at reasonable cost. That most of these solutions have not yet been implemented to any significant extent across the United States suggests that new policy approaches are necessary. The best solution may involve a combination of voluntary and mandatory approaches, applying different approaches to different sources of nitrogen poilution. A watershed-based approach that relies heavily on voluntary mechanisms (such as crop-yield insurance to reduce over-fertilization) is likely to be the most effective for some sources of nitrogen (such as runoff from agricultural fields), while a uniform national regulatory approach may be better for others (such as NOx emissions from fossil fuel combustion). Implementation of management strategies should be carefully coupled to monitoring programs to assess the effectiveness of these strategies. While both nitrogen and phosphorus are important to control, the focus should be on nitrogen management, in part because nitrogen is more generally the causal agent of coastal eutrophication. Also, while nitrogen-control practices tend to also reduce phosphorus pollution, phosphorus-control practices often have little effect on nitrogen.Although current scientific and technical knowledge is sufficient to begin to make substantial progress toward solving coastal nitrogen pollution, progress will be made more quickly and more cost effectively with increased investment in appropriate scientific research. 展开更多
关键词 development of POLICY approaches REDUCING nitrogen pollution coastal water of the USA.
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Mesozoic giant fleas from northeastern China (Siphonaptera):Taxonomy and implications for palaeodiversity 被引量:3
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作者 HUANG DiYing ENGEL Michael S +1 位作者 CAI ChenYang NEL André 《Chinese Science Bulletin》 SCIE EI CAS 2013年第14期1682-1690,共9页
The recently discovered definite giant fleas from the Middle Jurassic Daohugou fauna and the Early Cretaceous Jehol fauna of northeastern China represent significant evidence for understanding ectoparasitism in the Me... The recently discovered definite giant fleas from the Middle Jurassic Daohugou fauna and the Early Cretaceous Jehol fauna of northeastern China represent significant evidence for understanding ectoparasitism in the Mesozoic as well as the evolution of these giant blood feeders with their putative hosts (i.e. hairy or feathered vertebrates). On the basis of seven well-preserved specimens from Daohugou and Huangbanjigou we analyse the systematic classification of these primitive fleas, establishing two new genera and three new species as Pseudopulex wangi sp. nov., Hadropsylla sinica gen. et sp. nov., and Tyrannopsylla beipiaoensis gen. et sp. nov. All of them are assigned to the extinct siphonapteran family Pseudopulicidae, while the Early Cretaceous genus Tarwinia is transferred to Tarwiniidae fam. nov. The basal morphological disparities of Siphonaptera in the Mesozoic are evidenced by the occurrence of at least three distinct groups (pseudopulicids, tarwiniids, and saurophthirids). These disparate morphologies likely indicate adaptations to different hosts. 展开更多
关键词 中国东北地区 中生代 跳蚤 巨型 分类 东北部 早白垩世 形态差异
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Characterization of changes in land cover and carbon storage in Northeastern China:An analysis based on Landsat TM data 被引量:3
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作者 王绍强 田汉勤 +3 位作者 刘纪远 庄大方 张树文 胡文言 《Science China(Life Sciences)》 SCIE CAS 2002年第z1期40-47,共9页
We use Landsat TM time series data for the years of 1991/1992, 1995/1996 and 1999/2000 to characterize land-cover change in northeast China. With the information on land-cover change and the density of vegetation and ... We use Landsat TM time series data for the years of 1991/1992, 1995/1996 and 1999/2000 to characterize land-cover change in northeast China. With the information on land-cover change and the density of vegetation and soil carbon, we assess the potential effect of land-cover change on vegetation and soil carbon in this region. Our results show a large decrease of 2.76(104km2 in forest area and a rapid increase of 2.32(104km2 in urban area. Land-cover changes in northeast China have resulted in a potential maximum loss of 273.2 Tg C for the period of 1991-2000, with a net loss of 95.7 Tg C in vegetation and 177.5Tg C in soil. . The conversion of forests into other land-cover types could have potentially resulted in a loss of 254.6 Tg C for the study period, accounting for 68.8% of the total potential carbon loss in the northeast China. To quantify the net effect of land-cover change on carbon storage will require accounting for vegetation regrowth and soil processes. Our results also imply that forest protectionand reforestation are of critical importance to carbon sequestration in China. 展开更多
关键词 CARBON storage China deforestation LAND use.
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Take only pictures, leave only...fear? The effects of photography on the West Indian anole Anolis cristatellus 被引量:2
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作者 Brian HUANG Katie LUBARSKY Tiffany TENG Daniel T. BLUMSTEIN 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第1期77-82,共6页
关键词 野生动物摄影 西印度 图片 恐惧 时间显示 自然栖息地 生态旅游 快门
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Technical and conceptual considerations forusing animated stimuli in studies of animalbehavior 被引量:10
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作者 Laura CHOUINARD-THULY Stefanie GIERSZEWSKI +10 位作者 Gil G. ROSENTHAL Simon M. READER Guillaume RIEUCAU Kevin L. Woo Robert GERLAI Cynthia TEDORE Spencer J. INGLEY John R. STOWERS Joachim G.FROMMENI Francine L. DOLINS Klaudia WITTE 《Current Zoology》 SCIE CAS CSCD 2017年第1期5-19,共15页
Rapid technical advances in the field of computeropened new avenues in animal behavior research.animation (CA) and virtual reality (VR) haveAnimated stimuli are powerful tools as theyoffer standardization, repeata... Rapid technical advances in the field of computeropened new avenues in animal behavior research.animation (CA) and virtual reality (VR) haveAnimated stimuli are powerful tools as theyoffer standardization, repeatability, and complete control over the stimulus presented, thereby"reducing" and "replacing" the animals used, and "refining" the experimental design in line withthe 3Rs. However, appropriate use of these technologies raises conceptual and technical questions.In this review, we offer guidelines for common technical and conceptual considerations related tothe use of animated stimuli in animal behavior research. Following the steps required to create ananimated stimulus, we discuss (I) the creation, (11) the presentation, and (111) the validation of CAsand VRs. Although our review is geared toward computer-graphically designed stimuli, consider-ations on presentation and validation also apply to video playbacks. CA and VR allow both new be-havioral questions to be addressed and existing questions to be addressed in new ways, thus weexpect a rich future for these methods in both ultimate and proximate studies of animal behavior. 展开更多
关键词 ANIMAL behavior animated stimulus COMPUTER animation experimental design virtual reality visual communication.
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海南岛发现蓝翅八色鸫
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作者 梁斌 周润邦 +1 位作者 李波 王宁 《动物学杂志》 CAS CSCD 北大核心 2017年第4期726-726,共1页
2017年4月25日早晨,市民梁建美女士,在海南省海口市市区距离海岸不到1km的路边绿篱下(20°01′3i.93″N,110°18′29.70″E,海拔12m)救助1只鸟(图1)。经作者查阅文献(约翰·马敬能等2000),确认为蓝翅八色鸫(P... 2017年4月25日早晨,市民梁建美女士,在海南省海口市市区距离海岸不到1km的路边绿篱下(20°01′3i.93″N,110°18′29.70″E,海拔12m)救助1只鸟(图1)。经作者查阅文献(约翰·马敬能等2000),确认为蓝翅八色鸫(Pitta moluccensis),经检查该鸟羽毛完整,几乎没有磨损,排除人为笼养逃逸的可能,判断为自然过境或者迷鸟,确认为海南鸟类新纪录(郑光美2011)。 展开更多
关键词 海南岛 八色 鸟类 海口市 海南省 海拔
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Ornamental feathers in Cretaceous Burmese amber:resolving the enigma of rachis-dominated feather structure
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作者 Lida Xing Pierre Cockx +1 位作者 Ryan C.McKellar Jingmai O’Connor 《Journal of Palaeogeography》 SCIE CSCD 2019年第1期1-18,共18页
Over the last 20 years, compression fossils of feathers surrounding dinosaurs have greatly expanded our understanding of the origin and evolution of feathers. One of the most peculiar feather morphotypes discovered to... Over the last 20 years, compression fossils of feathers surrounding dinosaurs have greatly expanded our understanding of the origin and evolution of feathers. One of the most peculiar feather morphotypes discovered to date are rachis dominated feathers(RDFs), which have also been referred to as proximally ribbon-like pennaceous feathers(PRPFs). These elongate feathers are only found in the tail plumage, typically occurring in pairs with both streamer(not proximally ribbon-like) and racket-plume morphologies recognized. Here we describe a large sample set of isolated and paired RDFs from Upper Cretaceous Burmese amber(~ 99 Ma). Amber preserves the finest details of these fragile structures in three dimensions, demonstrating that RDFs form a distinct feather morphotype with a ventrally open rachis, and with significant variability in pigmentation, microstructure, and symmetry. 展开更多
关键词 Enantiornithes Confuciusornithiformes Fossil FEATHER Myanmar ORNAMENTAL FEATHER
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