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Rapid growth in a large Cambrian apex predator

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National Science Review 2024年第3期11卷 128-136页

作者：吴雨 Stephen Pates Daniel Pauly 张兴亮傅东静 State Key Laboratory of Continental Dynamics and Shaanxi Key Laboratory of Early Life and Environment Department of Geology Northwest University Department of Zoology University of Cambridge Institute for the Oceans and Fisheries University of British Columbia Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Despite the importance of ontogenetic data on early diverging euarthropods to our understanding of the ecology and evolution of past life, the data are distinctly lacking, as reconstructing life histories of fossil animals is often challenging. Here we report the growth trajectory of frontal appendages of the apex predator Amplectobelua symbrachiata, one of the most common radiodont arthropods from the early Cambrian Chengjiang biota(c. 520 Ma) of China. Analysis of 432 specimens(9.1–137.1 mm length; 1.3–25.6 mm height) reveals that appendages grew isometrically, with an estimated maximum size of the whole animal of c. 90 cm. Individuals grew rapidly compared to extant arthropods, as assessed using the electronic length-frequency analysis(ELEFAN) approach. Therefore, we show that the Cambrian apex predator A. symbrachiata was an extremely fast-growing arthropod, with an unusual life history strategy that formed as part of the escalatory ‘arms race’ that shaped the Cambrian explosion over 500 Ma.

关键词： stem-group Euarthropoda Radiodonta post-embryonic development growth dynamics Cambrian Explosion

Genesis of Silica-phosphatic Nodules with Small Shelly Fossils Preserved in the Lowermost Cambrian of South China

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1294-1307页

作者： QIU Hao FENG Lianjun CHU Xuelei LI Luoyang zhang xingliang LI Jinhua Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China State Key Laboratory of Continental Dynamics and Shaanxi Key Laboratory of Early Life and Environments Department of GeologyNorthwest UniversityXi’an 710069China

Silica-phosphatic nodules are abundant in black shales of the Yanjiahe Formation in the Three Gorges Area of South China,which is correlated to the Fortunian Stage,Terreneuvian Series,Cambrian System.The nodules are rich in small shelly fossils and hence attract the attention of numerous paleontologists and sedimentary geologists.However,the genesis of the nodules and the preservation of the small shelly fossils are poorly understood.Here we analyze morphological,structural,mineralogical and chemical features of the nodules in multiscale using a combination of micro-X-ray fluorescence spectroscopy,X-ray diffraction,scanning electron microscopy and confocal laser Raman spectroscopy.Results reveal that nodules are concentric in chemical and mineralogical compositions,comprising a silica-phosphatic core encrusted sequentially by a phosphatic zone,a siliceous zone and a very thin pyrite outer rim.The black shales hosting the nodules demonstrate a laminated texture of alternating clayey and silty laminae,which were respectively deposited in sulfidic/less sulfidic,high/low production,intense/weak chemical weathering conditions.The phosphogenesis of the nodules resulted in the phosphatization of small shelly fossils,which prevented the fossils from being dissolved during diagenesis,whereas the silica encrustation sealed the fossils within the nodules and thus protected the fossils from alteration by deep burial and surface weathering.

关键词： silica-phosphatic nodule small shelly fossils Yanjiahe Formation taphonomy Cambrian

Distinctive Scleritome with Marginal Tubercles of a New Palaeoscolecid Worm from the Shipai Fauna(Cambrian Epoch 2) at Three Gorges, South China

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 807-817页

作者： YANG Yuning zhang xingliang State Key Laboratory of Continental Dynamics Early Life Institute and Department of GeologyNorthwest University

SEM analysis of trunk ornamentation on a compressed palaeoscolecid fossil from the Shipai fauna, Cambrian Series 2 and Stage 4 at Three Gorges, South China, allows a reassignment of the material to a new taxon, Sanxiascolex papillogyrus gen. et sp. nov. The preserved body is entirely annulated. Each annulus is ornamented by four rows of irregularly alternating plates and each plate bears numerous tubercles at the marginal region and a variable number （zero to six） of nodes at its central part. These features are unique among known palaeoscolecids. Comparative analyses with other compressed palaeoscolecid macrofossils and phosphatized material on the pattern of trunk ornamentation indicates that a detailed examination of the cuticle ornament weighs heavily in analyses of their taxonomic distinctions. A similar sclerite pattern to that of S. papillogyrus has been found in some phosphatized palaeoscolecid cuticle fragments as well as in isolated sclerites. The upper series of nodes and tubercles of these sclerites suggest an accretional mode of sclerite growth. The considerable variation in node number observed across the plates of S. papillogyrus demonstrates that phosphatic palaeoscolecid taxonomy based on relatively minor variations in the number of selerite nodes should perhaps be reconsidered. As the origins of the phosphatized specimens are quite diverse, a large variety of isolated sclerites from the Early Palaeozoic may not reflect actual biodiversity.

关键词： Palaeoscolecida Sanxiascolex papillogyrus Cambrian Shipai fauna Three Gorges area South China

Calcified Biofilms from Cambrian Oolitic Limestones in China

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 70-76页

作者： LIU Wei zhang xingliang State Key Laboratory of Continental Dynamics and Department of Geology Northwest University

Calcified biofiims are preserved as thin micritic coatings in the Cambrian oolitic limestone of two sections in North and South China. Standard petrographic examination revealed that the biofilms were developed during the early diagenetic stage immediately after the freshly deposited ooids, proceeding in the continuous sequence of depositional processes. The biofilm outlines are highly irregular, with steep sides, tower-like structures and overhanging projections; the internal fabric of the biofilms is composed of roughly laminated micrite aggregates with channel-like structures. Biofilms exhibit a strong fluorescent reaction. Detailed SEM examination suggests that the biofilms are biotically dominated by cyanobacteria. Our study demonstrates that microbial colonies, such as biofilms, can develop on ooid cortices and influence the formation and microstructures of those ooids.

关键词： geobiology ooids micrite cyanobacteria Cambrian Hubei and Shaanxi provinces

Causes and consequences of the Cambrian explosion

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Science China Earth Sciences 2014年第5期57卷 930-942页

作者： zhang xingliang SHU DeGan State Key Laboratory of Continental Dynamics and Department of Geology Northwest University Early Life Institute Northwest University

The Cambrian explosion has long been a basic research frontier that concerns many scientific fields.Here we discuss the cause-effect links of the Cambrian explosion on the basis of first appearances of animal phyla in the fossil record,divergence time,environmental changes,Gene Regulatory Networks,and ecological feedbacks.The first appearances of phyla in the fossil record are obviously diachronous but relatively abrupt,concentrated in the first three stages of the Cambrian period(541–514 Ma).The actual divergence time may be deep or shallow.Since the gene regulatory networks(GRNs)that control the development of metazoans were in place before the divergence,the establishment of GRNs is necessary but insufficient for the Cambrian explosion.Thus the Cambrian explosion required environmental triggers.Nutrient availability,oxygenation,and change of seawater composition were potential environmental triggers.The nutrient input,e.g.,the phosphorus enrichment in the environment,would cause excess primary production,but it is not directly linked with diversity or disparity.Further increase of oxygen level and change of seawater composition during the Ediacaran-Cambrian transition were probably crucial environmental factors that caused the Cambrian explosion,but more detailed geochemical data are required.Many researchers prefer that the Cambrian explosion is an ecological phenomenon,that is,the unprecedented ecological success of metazoans during the Early Cambrian,but ecological effects need diverse and abundant animals.Therefore,the establishment of the ecological complexity among animals,and between animals and environments,is a consequence rather than a cause of the Cambrian explosion.It is no doubt that positive ecological feedbacks could facilitate the increase of biodiversity.In a word,the Cambrian explosion happened when environmental changes crossed critical thresholds,led to the initial formation of the metazoan-dominated ecosystem through a series of knock-on ecological processes,i.e.,"ecological snowball"effec

关键词：寒武纪大爆发原因基因调控网络生态效应环境因素后生动物生物多样性地球化学数据

碳排放权交易试点政策的公司治理效应——来自高管薪酬契约调整的证据

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工业技术经济 2024年第5期43卷 100-112页

作者：张兴亮周艺南京审计大学会计学院南京211815

公司治理是企业决策与行动的基础,研究碳排放权交易试点政策是否有公司治理效应,有助于厘清试点政策对环境治理的作用机制。本文认为,试点政策打破了股东与高管之间的博弈均衡,需要对高管薪酬契约进行调整以达到新的均衡。基于上市公司... 详细信息

公司治理是企业决策与行动的基础,研究碳排放权交易试点政策是否有公司治理效应,有助于厘清试点政策对环境治理的作用机制。本文认为,试点政策打破了股东与高管之间的博弈均衡,需要对高管薪酬契约进行调整以达到新的均衡。基于上市公司数据,研究发现,试点政策使企业调低了高管薪酬业绩敏感性,且在高碳行业中更显著;机制检验结果表明,由于试点政策降低了企业业绩,为了提高企业绿色转型的内部动力,企业做出降低高管薪酬业绩敏感性的决策。研究还发现,试点企业采用股权激励的可能性更高,并且那些降低高管薪酬业绩敏感性的试点企业会有更多的绿色创新和更好的ESG表现。本文是对研究试点政策效果文献的补充,也能为如何激发企业环境治理的内部动力提供启示。

关键词：公司治理效应碳排放权交易试点政策高管薪酬业绩敏感性股权激励绿色创新 ESG

Carbon isotopes, sulfur isotopes, and trace elements of the dolomites from the Dengying Formation in Zhenba area, southern Shaanxi: Implications for shallow water redox conditions during the terminal Ediacaran

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Science China Earth Sciences 2015年第7期58卷 1107-1122页

作者： CHEN YaLi CHU XueLei zhang xingliang ZHAI MingGuo State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences State Key Laboratory for the Continental Dynamics Northwest University

Carbon isotope, sulfur isotope, and trace element(including Rare Earth Elements, REE) analyses were conducted on the carbonates of the Dengying Formation at Lianghekou section in southern Shaanxi to reconstruct the terminal Ediacaran shallow-water environment on the northwestern margin of the Yangtze Platform. At Lianghekou section, samples in the middle 50-m of the Beiwan Member show characteristics of low ΣREE concentrations, no MREE-enriched REE distribution patterns, high Ce/Ce* values close to 1, and enriched redox-sensitive elements, whereas samples in the lower 30-m and upper 10-m show opposite characteristics of high ∑REE concentrations, MREE-enriched REE distribution patterns, low Ce/Ce* values around 0.6, and no redox-sensitive elements enriched, indicating that oxygenation did occur in the shallow water on the northwestern margin of the Yangtze Platform and redox conditions of the shallow water fluctuated from relatively oxygenated to anoxic and then back to oxygenated again. We propose that the anoxia appeared in middle of the Beiwan time may associate with the anoxic upwelled water. On one hand, abundant nutrients were brought in by this upwelling event, which stimulated the photosynthetic carbon fixation and increased the organic carbon burial under this anoxic condition, causing a peak of 3.6‰ in δ 13 C. On the other hand, because the anoxic upwelled water replaced the oxic shallow water, together with the increasing organic matter in the water column, bacterial sulfate reduction was enhanced and therefore quickly reduced the sulfate concentration, which eventually caused δ 34 S increasing to 50‰. However, as the upwelling gradually disappeared, δ 13 C and δ 34 SCAS values decreased as well in the late Beiwan time, indicating the shallow water went back to suboxic or oxic again.

关键词：氧化还原条件浅水环境微量元素碳同位素陕西南部硫同位素灯影组迪卡

Systematic Revision of Trilobites from the Middle Ordovician(Darriwilian) Klimoli Formation of the Zhuozishan Area,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 1955-1975页

作者： LEE Seung-Bae LEE Dong-Chan WOO Jusun zhang xingliang Geology Division Korea Institute of Geoscience and Mineral Resources Department of Earth Science Education Chungbuk National University Division of Polar Earth-System Sciences Korea Polar Research Institute Early Life Institute and State Key Laboratory of Continental Dynamics Department of GeologyNorthwest University

New morphologic information permits systematic revision of trilobites from the Middle Ordovician Klimoli Formation of the Zhuozishan area, Ordos Basin, Inner Mongolia. The new assemblage is composed of 10 species of the Raphiophoridae, Nileidae, Asaphidae, and Telephinidae.？ An asaphid, aff. Mioptychopyge lashachungensis （previously Paraptychopyge lashachungensis） displays an intermediate morphology between the Chinese nobiliasaphine genera Mioptychopyge and Zhenganites. The pygidial doublure is regarded as the most significant character to differentiate Symphysurus klimoliensis （previously Nileus klimoliensis） of the Nileidae from such closely allied taxa as Poronileus. A nileid, cf. Peraspis kujandensis displays typical nileid morphology, unlike the type species, Peraspis lineolata, which might turn out to be an asaphid. Ampyx gongwusuensis sp. nov. of the Raphiophoridae is the first record of the genus in the Zhuozishan area and reveals morphologic details that might be employed to resolve Ampyx taxonomy in China. Morphologic differences between A. gongwusuensis and Abulbaspis ordosensis might represent a case of sexual dimorphism.

关键词： Invertebrate paleontology Trilobita systematics Klimoli Formation Darriwilian Zhuozishan Inner Mongolia

Dimorphism of Bivalved Arthropod Branchiocaris？ Yunnanensis from the Early Cambrian Chengjiang Biota, South China

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 818-826页

作者： WU Yu FU Dongjing zhang xingliang Allison C. DALEY SHU Degan Early Life Institute and State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi 'an 710069 China Department of Zoology University of Oxford South Parks Road Oxford OX1 3PS UK Oxford University Museum of Natural History Parks Road Oxford OX1 3PW UK

The bivalved arthropod Branchiocaris？ yunnanensis Hou, 1987 is redescribed on the basis of new fossil material from the early Cambrian Chengjiang biota, South China. In total, 81 specimens have been examined. The carapace comprises two identical valves, each valve are sub-circular in outline, ranging from 24 mm to 58 mm in length, and from 15 mm to 46 mm in height. The dorsal margin is straight and bears two short cardinal spines. The valve surface is either smooth or ornamented with polygonal reticular structures, which may result from different preservation conditions. Two morphotypes have been recognized based on the presence or absence of a subdorsal swelling of the valve, which is convex dorsolaterally and extends beyond the dorsal margin when it appears. Statistic and ontogenetic analyses show both morphotypes grow isometrically and have the same growth trajectory. Therefore, the two morphotypes are interpreted as dimorphism within the same species. Our results are helpful for investigating the taxonomy and ontogeny of arthropod fossils and suggest that dimorphism might be fairly common in these early arthropods.

关键词： Arthropoda Branchiocaris Dimorphism Ontogeny Chengjiang biota