taphonomy

taphonomy
  • 文章类型: Journal Article
    瑞士是鱼龙国家:它有丰富的海洋爬行动物化石记录,尤其是鱼形鱼龙,和根据研究。这里,我们提供了12个或更多属和至少13个物种的概述,以及迄今为止在12个州发现的从三叠纪到白垩纪的大量碎片,其中四种是基于瑞士的完整型。这种丰富的鱼龙物种可以通过它们在MonteSanGiorgio的中三叠纪保护矿床(KonservatLagerstätte)中的丰富来解释,以及在中三叠纪至白垩纪早期的地层中偶尔发现。在合理的条件下露头的适度丰度与瑞士古生物学研究的悠久历史相结合,解释了这一良好的化石记录。除了这个独特的概述,我们为进一步的研究提供了更多的数据,并更新了这些分类单元的知识。
    Switzerland is an ichthyosaur country: it has a rich record of marine reptile fossils, particularly the fish-shaped ichthyosaurs, and the according research. Here, we provide an overview over the 12 or more genera and at least 13 species plus numerous fragmentary remains of ichthyosaurs from the Triassic to the Cretaceous that have been discovered in twelve cantons thus far, of which four species are based on Swiss holotypes. This wealth of ichthyosaur species can be explained by their abundance in the Middle Triassic conservation deposits (Konservat Lagerstätte) of Monte San Giorgio, as well as occasional discoveries in strata of Middle Triassic to Early Cretaceous age. The moderate abundance of outcrops in reasonable conditions in combination with the long history of palaeontological research in Switzerland explains this good fossil record. In addition to this unique overview, we provide more data for further studies and update the knowledge of these taxa.
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  • 文章类型: Journal Article
    长期以来,呈现热引起的变化的骨骼人类遗骸一直是研究的重点。然而,人类学家要充分解释和理解这些变化还有很长的路要走。热引起的颜色修饰是骨骼中最不了解的现象之一,显示各种例外(例如,黄色的色彩,橙色,蓝色,绿色,粉色,和红色)到骨骼暴露于高温时可以产生的预期颜色变化(即,象牙,棕色,黑色,各种深浅的灰色,和白色)。除了这些,关于确定观察到的确切颜色和使用的命名法的方法,文献中缺乏均匀化,让位于主观描述。然而,在最近的研究中可以看到对更客观和可靠方法的承诺。在这次审查中,我们汇编了多年来在文献中发表的数据,以描述有关热引起的颜色变化的可能性,以推断死亡情况以及这些方法在法律框架中的适用性。
    Skeletal human remains presenting heat-induced changes have been a focus of study for a long time. However, there is still a long way to go for the anthropologists to be able to fully interpret and understand these changes. Heat-induced colour modifications are one of the least understood phenomena in bone, displaying a variety of exceptions (e.g., tints of yellow, orange, blue, green, pink, and red) to the expected colour variations that bone can produce when exposed to high temperatures (i.e., ivory, brown, black, various shades of grey, and white). In addition to these, there is a lack of uniformization in the literature regarding the methods to determine the exact colourations observed and the nomenclature used, giving way to subjective descriptions. However, commitment to more objective and reliable methods is visible in more recent research. In this review, we compiled data published in the literature throughout the years to portray the state of the art regarding the potential of heat-induced colour changes for inferring the circumstances of death and the applicability of these methods in the legal framework.
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  • 文章类型: Journal Article
    骨骼遗骸的鉴定,腐败严重受损,或者严重恶化,出于法律和人道主义原因。有不同的工具可以帮助识别过程,如人类学和遗传研究。在过去十年中,骨骼遗骸的遗传分析取得了成功,尤其是由于DNA提取和后验分析技术的改进。然而,尽管取得了这些进展,许多挑战不断影响这种分析的结果,主要是从保存不良的样品中回收的DNA的数量有限和降解。到现在为止,关于DNA降解的事后动力学仍然没有广泛的知识。因此,taphonomy研究可以在骨骼遗骸的死后转化的重建中发挥关键作用,因此DNA,已经经历了。因此,本综述的目的是评估有关内在(骨骼特征)和外在(环境)因素对陆地环境中恢复的骨骼遗骸及其遗传物质的保存状态的可能影响的文献。建立描述遗骸状态的有用指标是确定其是否适合进行后验生物分子分析的关键因素。
    The identification of skeletal human remains, severely compromised by putrefaction, or highly deteriorated, is important for legal and humanitarian reasons. There are different tools that can help in the identification process such as anthropological and genetic studies. The success observed during the last decade in genetic analysis of skeletal remains has been possible especially due to the refinements of DNA extraction and posterior analysis techniques. However, despite these progresses, many challenges keep influencing the results of such analysis, mainly the limited amount and the degradation of the DNA recovered from badly preserved samples. By now, there is still no wide-range knowledge about post-mortem kinetics of DNA degradation. Therefore, taphonomy studies can play a key role in the reconstruction of post-mortem transformations that skeletal remains, and consequently DNA, have undergone. Thus, the goal of the present review focuses on the assessment of the literature regarding the possible effect of intrinsic (characteristics of the bone) and extrinsic (environmental) factors on the state of preservation of skeletal remains recovered in a terrestrial environment and their genetic material. The establishment of useful indicators describing the state of the remains is a key factor in order to determine their suitability for posterior biomolecular analysis.
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  • 文章类型: Historical Article
    The dating of organic findings is a fundamental task for many scientific fields. Radiocarbon dating is currently the most commonly used method. For wood, dendrochronology is another state-of-the-art method. Both methods suffer from systematic restrictions, leading to samples that have not yet been able to be dated. Molecular changes over time are reported for many materials under different preservation conditions. Many of them are intrinsically monotonous. These monotonous molecular decay (MD) patterns can be understood as clocks that start at the time when a given molecule was formed. Factors that influence these clocks include input material composition and preservation conditions. Different wood species, degrees of pyrolysis, and pretreatments lead to different prediction models. Preservation conditions might change the speed of a given clock and lead to different prediction models. Currently published models for predicting the age of wood, paper, and parchment depend on infrared spectroscopy. In contrast to radiocarbon dating, dating via MD does not comprise a single methodology. Some clocks may deliver less precise results than the others. Ultimately, developing a completely different, new dating strategy-such as MD dating-will help to bring to light a treasure trove of information hidden in the darkness of organic findings.
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  • 文章类型: Journal Article
    对于二十一世纪的寄生虫学家来说,认识到寄生虫的存在并识别它是一项相对简单的任务。不那么追求化石生物中的古代寄生虫,一个更困难的命题。在这里,Boucot的七层可靠性类别方案被用作两个棘皮动物类别中推定寄生的识别置信度的度量,上古生代海百合类及一白垩纪类(高置信度为1,低置信度为7)。在这五个例子中,寄生(?)生物只保存在其中两个中。膜状海百合上的zaphrentoid珊瑚可能从武器中抢走了食物(1类或2B类)。在异类海百合Synbatocrinus上似乎是精心选择的部位的凹坑与杯子的生长畸形有关(类别4)。Amphoracrinustheca中的多个凹坑也与变形的杯子有关,但它更难解释(类别4或7)。囊状海百合的一些标本在后部有圆形凹槽或凹陷,推测是由同代/寄生的鸭嘴兽腹足动物(第1类)产生的。类半针中凹坑的位置选择性使它们优先靠近呼吸管脚(类别4)。从这些例子中可以推断,稀疏侵染的钻孔或地生代生物可以更自信地解释生物体/生物体的相互作用;密集的积累,可能是在多次碰撞之后,掩盖这样的模式。
    Recognizing the presence of a parasite and identifying it is a relatively straightforward task for the twenty-first century parasitologist. Not so the pursuit of ancient parasites in fossil organisms, a much more difficult proposition. Herein, Boucot\'s seven-tiered scheme of reliability classes is applied as a measure of confidence of the recognition of putative parasitism in two echinoderm classes, Upper Palaeozoic crinoids and a Cretaceous echinoid (high confidence is 1, low confidence 7). Of the five examples, the parasitic(?) organism is preserved in only two of them. A zaphrentoid coral on the camerate crinoid Amphoracrinus may have robbed food from the arms (Category 1 or 2B). A pit in what appears to be a carefully selected site on the disparid crinoid Synbathocrinus is associated with a growth deformity of the cup (Category 4). Multiple pits in an Amphoracrinus theca are also associated with a deformed cup, but it is more difficult to interpret (Category 4 or 7). Some specimens of the camerate crinoid Neoplatycrinites have circular grooves or depressions posteriorly, presumably produced by coprophagic/parasitic platyceratid gastropods (Category 1). Site selectivity of pits in the echinoid Hemipneustes places them preferentially adjacent to respiratory tube feet (Category 4). From these examples it is deduced that sparse infestations of borings or epizoozoic organisms permit a more confident interpretation of organism/organism interactions; dense accumulations, possibly following multiple spatfalls, mask such patterns.
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