Paleontology

古生物学
  • 文章类型: Journal Article
    白垩纪晚期是海平面较高的时期,它使整个特提斯王国拥有广泛的陆生海道和碳酸盐平台,为牡蛎群落提供有利的栖息地。这项研究的重点是来自埃及东北沙漠的坎帕尼亚特提斯牡蛎的分类学,古生态学,和古生物地理学。三种牡蛎,Nicaisolophanicaisei(Coquand,1862),Pycnodonte(Phygraea)囊泡(Lamarck,1806),和Ambigostreabretoni(Thomas和Peron,1891),在两个研究部分中从坎帕尼亚演替中确定。Nicaisolopha属的样本样本经过了系统的古生物学修订。因此,N.Tissoti(托马斯和佩隆,1891)在这里被认为是N.nicaisei(Coquand,1862).古生物地理,所研究牡蛎可能的主要迁徙模式表明,沿着南特提斯边缘呈东西向趋势。在这项研究中,所有确定的牡蛎都具有特提斯亲和力,并且主要在两个主要省份中丰富:南部特提斯和西部特提斯。大型动物群的内容物分为两个化石协会:坎帕尼亚中晚期年龄的Nicaisolophanicaiserisei协会和坎帕尼亚晚期年龄的Pynodontevicularis协会。这些大型动物协会表明,在坎帕尼亚时代中晚期,表明从浅层的内在环境过渡到中等的环境。此外,观察到Pycnodonteinae在富营养化条件下倾向于变大,低能耗环境,和高碳酸盐含量的营养丰富的水域。
    The Late Cretaceous was a time of high eustatic sea level that enabled extensive epicontinental seaways and carbonate platforms across the Tethyan Realm, providing favorable habitats for oyster communities to flourish. This study focuses on the Campanian Tethyan oysters from the North Eastern Desert of Egypt regarding taxonomy, palaeoecology, and palaeobiogeography. Three oyster species, Nicaisolopha nicaisei (Coquand, 1862), Pycnodonte (Phygraea) vesicularis (Lamarck, 1806), and Ambigostrea bretoni (Thomas and Peron, 1891), were identified from the Campanian succession in two studied sections. The sampled specimens of the genus Nicaisolopha have undergone a systematic palaeontological revision. As a result, N. tissoti (Thomas and Peron, 1891) is considered herein a junior synonym of N. nicaisei (Coquand, 1862). Palaeobiogeographically, the likely primary migration pattern of the studied oysters suggests an east-west trend along the Southern Tethys margin. All identified oysters in this study exhibit a Tethyan affinity and are primarily abundant in two main provinces: the Southern Tethys and the Western Tethys. The macrofaunal contents are categorized into two fossil associations: the Nicaisolopha nicaisei association of the middle-late Campanian age and the Pycnodonte vesicularis association of the late Campanian age. These macrofaunal associations indicate a deepening trend during the middle-late Campanian age, suggesting a transition from shallow inner neritic to middle neritic environments. Additionally, it is observed that Pycnodonteinae tend to grow larger under eutrophic conditions, low-energy environments, and nutrient-rich waters with high carbonate contents.
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  • 文章类型: Journal Article
    对矿物凝结物中保存完好的有机物(OM)的研究为深入了解沉积和环境条件提供了关键见解。各种成分的凝结,包括碳酸盐,磷酸盐,和铁基矿物,被发现拥有异常保存的化石。包裹有结石的OM的有机地球化学表征有望提供有价值的化石保存新信息,古环境,甚至直接的分类信息来进一步阐明我们星球及其生物群的进化动态。充分利用这个尚未开发的地球化学档案,然而,需要对患病率有深入的了解,矿物凝结的形成控制和OM固存特性。过去的研究导致提出了不同的结石形成和OM保存模型。然而,对结石中OM保存的形成机制和控制仍知之甚少。在这里,我们提供了一个详细的审查的主要类型的结石和形成途径,重点是微生物的作用和它们的代谢活动。此外,我们提供了有机地球化学的全面描述,和免费的无机地球化学,形态学,微生物和古生物学,分析方法,包括最近的进步,与结石和隔离OM的表征有关。包括一些早期的凝结物浸渍OM有机地球化学研究的应用和结果,以证明这种未充分利用的地质生物记录如何为地球的进化记录提供新的见解。本文还试图阐明该研究的现状以及在进一步应用古生物微生物和有机地球化学研究中面临的主要挑战。还讨论了最近为弥合这个多学科研究领域的知识和交流差距所做的努力。特别强调对解释非常保存的化石中的分子记录具有重要意义的研究。
    The study of well-preserved organic matter (OM) within mineral concretions has provided key insights into depositional and environmental conditions in deep time. Concretions of varied compositions, including carbonate, phosphate, and iron-based minerals, have been found to host exceptionally preserved fossils. Organic geochemical characterization of concretion-encapsulated OM promises valuable new information of fossil preservation, paleoenvironments, and even direct taxonomic information to further illuminate the evolutionary dynamics of our planet and its biota. Full exploitation of this largely untapped geochemical archive, however, requires a sophisticated understanding of the prevalence, formation controls and OM sequestration properties of mineral concretions. Past research has led to the proposal of different models of concretion formation and OM preservation. Nevertheless, the formation mechanisms and controls on OM preservation in concretions remain poorly understood. Here we provide a detailed review of the main types of concretions and formation pathways with a focus on the role of microbes and their metabolic activities. In addition, we provide a comprehensive account of organic geochemical, and complimentary inorganic geochemical, morphological, microbial and paleontological, analytical methods, including recent advancements, relevant to the characterization of concretions and sequestered OM. The application and outcome of several early organic geochemical studies of concretion-impregnated OM are included to demonstrate how this underexploited geo-biological record can provide new insights into the Earth\'s evolutionary record. This paper also attempts to shed light on the current status of this research and major challenges that lie ahead in the further application of geo-paleo-microbial and organic geochemical research of concretions and their host fossils. Recent efforts to bridge the knowledge and communication gaps in this multidisciplinary research area are also discussed, with particular emphasis on research with significance for interpreting the molecular record in extraordinarily preserved fossils.
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  • 文章类型: Historical Article
    我们对生物地理学的历史学研究进行了严格的回顾。我们从奥古斯丁和AlphonsedeCandolle的开创性作品开始。然后,我们分析了由(1)马丁·菲赫曼及其关于扩展-永久主义辩论的历史;(2)加雷斯·纳尔逊及其对新达尔文生物地理学史学的批评;(3)恩斯特·迈尔,以他的分散主义观点;(4)艾伦·理查森,他写了一篇关于达尔文构建的生物地理模型的微观历史;(5)迈克尔·保罗·金奇和19世纪讨论的关于生物地理分布的思想;(6)珍妮特·布朗,他强调了前达尔文博物学家的重要性;(7)彼得·鲍勒,他主要关注古生物学对生物地理学的影响;(8)詹姆斯·拉尔森,他研究了18世纪末北欧博物学家的做法;(9)马尔特·埃巴赫,喜欢Larson的人,更感兴趣的是分析实践,而不是研究生物地理分布的自然主义者的想法。最后,这些作品是相互比较的。在生物地理学历史叙事的建构中,还没有一个占主导地位的范式;然而,它们为理解生物地理学的问题提供了有用的背景,这些问题至今仍在争论中。
    We performed a critical review of the historiographical studies on biogeography. We began with the pioneering works of Augustin and Alphonse de Candolle. Then, we analyzed the historical accounts of biogeography developed by (1) Martin Fichman and his history on the extensionism-permanentism debate; (2) Gareth Nelson and his critique of the Neo-Darwinian historiography of biogeography; (3) Ernst Mayr, with his dispersalist viewpoint; (4) Alan Richardson, who wrote a microhistory on the biogeographic model constructed by Darwin; (5) Michael Paul Kinch and the ideas discussed in the 19th century about the geographical distribution of living beings; (6) Janet Browne, who highlighted the importance of the pre-Darwinian naturalists; (7) Peter Bowler, who focused mainly on the influence of paleontology on biogeography; (8) James Larson, who looked into the practices of the naturalists of Northern Europe in the late 18th century; and (9) Malte Ebach, who like Larson, was more interested in analysing the practices rather than the ideas of naturalists who studied the geographical distribution of organisms. Finally, these works are compared with each other. There has not been a dominant paradigm in the construction of historical narratives of biogeography; however, they provide a useful context for understanding problems of biogeography that continue to be debated to this day.
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  • 文章类型: Review
    有限元分析(FEA)不再是古生物学领域的新技术,人类学,和进化生物学。如今,它是虚拟功能形态学工具包中的一种完善的技术。然而,几乎所有在这些领域发表的作品都只应用了最基本的有限元分析工具,即静态结构问题中的线性材料。线性和静态近似是常用的,因为它们的计算成本较低,与这些假设相关的错误是可以接受的。尽管如此,在生物力学模型中使用非线性是很自然的,特别是在对软组织建模时,在分离的骨骼之间建立接触或包含屈曲结果。这次审查的目的是,首先,强调非线性的有用性,其次,向从事功能形态学和生物力学工作的研究人员展示这些FEA工具,因为非线性可以通过扩大目前在古生物学和人类学中未使用的可能应用和主题来改善其FEA模型。
    Finite element analysis (FEA) is no longer a new technique in the fields of palaeontology, anthropology, and evolutionary biology. It is nowadays a well-established technique within the virtual functional-morphology toolkit. However, almost all the works published in these fields have only applied the most basic FEA tools i.e., linear materials in static structural problems. Linear and static approximations are commonly used because they are computationally less expensive, and the error associated with these assumptions can be accepted. Nonetheless, nonlinearities are natural to be used in biomechanical models especially when modelling soft tissues, establish contacts between separated bones or the inclusion of buckling results. The aim of this review is to, firstly, highlight the usefulness of non-linearities and secondly, showcase these FEA tool to researchers that work in functional morphology and biomechanics, as non-linearities can improve their FEA models by widening the possible applications and topics that currently are not used in palaeontology and anthropology.
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  • 文章类型: Journal Article
    蓝细菌代谢产物的研究越来越多,关于它们的生物合成,生态作用,毒性,和潜在的生物医学应用。然而,在过去的几十年中,氰基毒素的历史几乎是未知的。迄今为止,仅进行了一些古生物学研究,这些都集中在微囊藻毒素和圆柱精视蛋白,两者都在200年和4700年的湖泊沉积物中成功发现,分别。在本文中,我们回顾了直接提取,量化,以及氰基毒素在沉积物岩心中的应用,并提出了该领域未来的研究展望。蓝藻毒素研究也与其他古蓝藻工具进行了比较,如沉积颜料,akinetes,和古老的DNA分离,以确定每个工具在再现蓝藻历史中的作用。这样的研究也可能有利于进一步阐明氰基毒素的生物学作用。特别是如果再加上对其他非生物和生物沉积特征的分析。此外,我们确定了当前的局限性以及未来在古分子生物学研究中氰基毒素的应用方向。
    Cyanobacterial metabolites are increasingly studied, in regards to their biosynthesis, ecological role, toxicity, and potential biomedical applications. However, the history of cyanotoxins prior to the last few decades is virtually unknown. Only a few paleolimnological studies have been undertaken to date, and these have focused exclusively on microcystins and cylindrospermopsins, both successfully identified in lake sediments up to 200 and 4700 years old, respectively. In this paper, we review direct extraction, quantification, and application of cyanotoxins in sediment cores, and put forward future research prospects in this field. Cyanobacterial toxin research is also compared to other paleo-cyanobacteria tools, such as sedimentary pigments, akinetes, and ancient DNA isolation, to identify the role of each tool in reproducing the history of cyanobacteria. Such investigations may also be beneficial for further elucidation of the biological role of cyanotoxins, particularly if coupled with analyses of other abiotic and biotic sedimentary features. In addition, we identify current limitations as well as future directions for applications in the field of paleolimnological studies on cyanotoxins.
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  • 文章类型: Historical Article
    The scientific study of the victims of the 79 AD Vesuvius eruption began with the first discovery in the 1980s of hundreds of skeletons of people who had taken refuge in the suburban area of Herculaneum. Hundreds of human victims were found crowding the beach and a series of waterfront chambers, fixated into a final posture by the first of the deadly incoming pyroclastic currents. The towns of Herculaneum, Pompeii and other Roman settlements up to 20 kilometers away were suddenly hit and overwhelmed by successive ash-avalanches, fast moving clouds of hot volcanic ash and gases known as pyroclastic surges, capable of killing all residents who were not yet evacuated. Given the impossibility of access to the skeletal remains of the Pompeiians locked within the plaster casts and the sparse occasional finds of victims elsewhere, most of the anthropological studies focused on the victims discovered in Herculaneum. The first investigations were carried out to detect the biological and pathological features of these people. More recent multidisciplinary studies on the victims\' skeletons and their volcanological context shed light on the dynamic impacts of the 79 AD Plinian eruption on the area around the volcano and on its inhabitants. The effects of the high temperatures of the surges as suffered by the remaining resident population were revealed, with crucial implications for the present-day risk of a similar outcome to around three million people living close to the volcano, including metropolitan Naples.
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  • 文章类型: Journal Article
    在这里,我们回顾了有关陆地岩石承载生命的丰度和多样性的已发表研究,它所居住的环境,它的新陈代谢的进化,以及它的化石生物标记物,为寻找火星上的生命提供指导。主要发现是(1)许多陆地深层地下代谢活动依赖于非生物的能量产生通量以及代谢废物的原位非生物和生物循环利用,而不是光合作用的埋藏有机产物;(2)地下微生物细胞浓度在具有明显化学氧化还原梯度或渗透性变化的界面处最高,并且与块状宿主岩石有机碳无关;(3)化学自养微生物的代谢途径在地球上的早期出现时(火星可生长)而后者的出现是在火星表面无法持续居住的时候发生的;(5)陆地岩石记录具有至少几亿年前的地下生命生物标志物,并且可能达到3.45Ga,其中有几个在岩石类型中保存出色的例子,这些例子与保存光球支持的生物圈的岩石类型完全不同。这些发现表明,在火星背景下,岩石承载的生命更有可能出现并保存下来。因此,我们概述了火星探测策略,该策略针对地下生命和空间尺度,首先侧重于识别具有地下水流动和低温矿化证据的岩石,然后确定保留在岩石露头中的氧化还原和渗透性界面,最后专注于寻找与氧化还原反应相关的矿物质和相关的碳痕迹以及诊断化学和同位素生物特征。在地球上使用这种策略会产生古老的岩石托管生命,保存在化石记录中,并通过一套形态学证实,有机,矿物学,和微米级同位素指纹。我们希望强调岩石承载的生命和这种依赖于规模的策略对于在火星上寻找生命至关重要。
    Here we review published studies on the abundance and diversity of terrestrial rock-hosted life, the environments it inhabits, the evolution of its metabolisms, and its fossil biomarkers to provide guidance in the search for life on Mars. Key findings are (1) much terrestrial deep subsurface metabolic activity relies on abiotic energy-yielding fluxes and in situ abiotic and biotic recycling of metabolic waste products rather than on buried organic products of photosynthesis; (2) subsurface microbial cell concentrations are highest at interfaces with pronounced chemical redox gradients or permeability variations and do not correlate with bulk host rock organic carbon; (3) metabolic pathways for chemolithoautotrophic microorganisms evolved earlier in Earth\'s history than those of surface-dwelling phototrophic microorganisms; (4) the emergence of the former occurred at a time when Mars was habitable, whereas the emergence of the latter occurred at a time when the martian surface was not continually habitable; (5) the terrestrial rock record has biomarkers of subsurface life at least back hundreds of millions of years and likely to 3.45 Ga with several examples of excellent preservation in rock types that are quite different from those preserving the photosphere-supported biosphere. These findings suggest that rock-hosted life would have been more likely to emerge and be preserved in a martian context. Consequently, we outline a Mars exploration strategy that targets subsurface life and scales spatially, focusing initially on identifying rocks with evidence for groundwater flow and low-temperature mineralization, then identifying redox and permeability interfaces preserved within rock outcrops, and finally focusing on finding minerals associated with redox reactions and associated traces of carbon and diagnostic chemical and isotopic biosignatures. Using this strategy on Earth yields ancient rock-hosted life, preserved in the fossil record and confirmable via a suite of morphologic, organic, mineralogical, and isotopic fingerprints at micrometer scale. We expect an emphasis on rock-hosted life and this scale-dependent strategy to be crucial in the search for life on Mars.
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    文章类型: Historical Article
    Paleoparasitology was created to trace and recover the natural development of parasites as well as the origin of infectious diseases. Paleoparasitology is defined as the study of parasites in ancient material and their interactions with hosts and vectors. Advances in the field have helped to open up new prospects for anthropologists, archaeologists, biologists and medical scientists. In recent years, Iranian parasitologists and biologists have developed immense interest in this field. One of the first human settlements on earth was established in Iran and there is extensive evidence of early human life in this ancient land. Therefore, the aim of the review was to assess paleoparasitological research conducted in Iran in order to facilitate the discovery of the origin of infectious diseases in the region. English and Persian electronic databases including Web of Science, Sciencedirect, PubMed, Scopus, Google Scholar, Iran Doc, SID, Iran Medex and Magiran were employed as search engines (up to 2017) using the keywords: Iran, Islamic Republic of Iran, Parasitology, Parasites and Archaeology. According to the current review, the results of the parasitological study revealed the incidence of human and animal parasitic infection in Iran dating back to 8100 BC.
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  • 文章类型: Journal Article
    The Mylodontidae Scelidotheriinae (Mammalia, Xenarthra, Tardigrada) are a diversified clade of South American fossil ground sloths, with a wide geographic distribution, especially in high and middle latitudes. According to the last revision, the Quaternary diversity includes the genera Scelidotherium, Catonyx, and Valgipes. The clade Scelidotheriinae is well represented in the Pleistocene of the Tarija-Padcaya basin, and the first mention of these ground sloths correspond to the middle of the XIX Century. Since then, several species (i.e., Scelidotherium tarijensis, Scelidodon tarijensis, Scelidotherium capellini) have been reported as inhabiting the Tarija-Padcaya basin during the Pleistocene. Despite the abundance of fossil records of Scelidotheriinae in this area, no modern taxonomic revisions are available. In consequence, in this contribution a revision of the remains assigned to Scelidotheriinae from the Tarija-Padcaya basin is accomplished, and some biostratigraphic and geographic implications are discussed. Our results show that one single species (Catonyx tarijensis) can be recognized in the studied area, whereas a supposed smaller one (Scelidotherium patrium) actually corresponds to juvenile specimens of C. tarijensis.
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  • 文章类型: Journal Article
    The Pleistocene vertebrate assemblage of Aldabra Atoll has been comparatively well studied. Three Upper Pleistocene fossil localities have been described yielding birds, reptiles and terrestrial molluscs. Those of Bassin Cabri and Bassin Lebine on Ile Picard are undated but must be in excess of 136,000 YBP, whereas Point Hodoul on Malabar Island is circa 100,000 YBP. Aldabra was seemingly completely submerged between deposition of the Ile Picard and Point Hodoul deposits, resulting in local faunal extinctions. Here we present the results of an ongoing study of fossil material collected on Ile Picard in 1987, which reveals a more diverse assemblage than previously realised. Notable discoveries are an Ardeola heron, three Procellariformes, tropic-bird Phaethon, gull Larus, rail Dryolimnas, harrier Circus and owl Tyto, plus evidence of recolonisation of the atoll by some seabirds, rail, harrier, owl, giant tortoises and lizards after the Ile Picard/Point Hodoul submergence event.
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