Fossils from South China redefine the ancestral euarthropod body plan

Abstract Background Early Cambrian Lagerstätten from China have greatly enriched our perspective on the early evolution of animals, particularly arthropods. However, recent studies have shown that many of these early fossil arthropods were more derived than previously thought, casting uncertainty on the ancestral euarthropod body plan. In addition, evidence from fossilized neural tissues conflicts with external morphology, in particular regarding the homology of the frontalmost appendage. Results Here we redescribe the multisegmented megacheirans Fortiforceps and Jianfengia and describe Sklerolibyon maomima gen. et sp. nov., which we place in Jianfengiidae, fam. nov. (in Megacheira, emended). We find that jianfengiids show high morphological diversity among megacheirans, both in trunk ornamentation and head anatomy, which encompasses from 2 to 4 post-frontal appendage pairs. These taxa are also characterized by elongate podomeres likely forming seven-segmented endopods, which were misinterpreted in their original descriptions. Plesiomorphic traits also clarify their connection with more ancestral taxa. The structure and position of the “great appendages” relative to likely sensory antero-medial protrusions, as well as the presence of optic peduncles and sclerites, point to an overall homology with the anterior head of radiodontans. This is confirmed by our Bayesian phylogeny, which places jianfengiids as the basalmost euarthropods, paraphyletic with other megacheirans, and in contiguity with isoxyids and radiodontans. Conclusions Sklerolibyon and other jianfengiids expand the disparity of megacheirans and suggest that the common euarthropod ancestor possessed a remarkable phenotypic variability associated with the externalized cephalon, as well as endopods that were already heptopodomerous, which differs from previous hypotheses and observations. These animals also demonstrate that the frontalmost pair of arthrodized appendage is homologous between radiodontans and megacheirans, refuting the claim that the radiodontan frontal appendages evolved into the euarthropod labrum, and questioning its protocerebral identity. This evidence based on external anatomy now constitutes a solid benchmark upon which we should address issues of homology, with the help of carefully examined palaeoneurological data.

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Macroscopic carbonaceous compressions in a terminal Proterozoic shale: A systematic reassessment of the Miaohe biota, south China

Journal of Paleontology ◽

10.1017/s0022336000041743 ◽

2002 ◽

Vol 76 (2) ◽

pp. 347-376 ◽

Cited By ~ 129

Author(s):

Shuhai Xiao ◽

Xunlai Yuan ◽

Michael Steiner ◽

Andrew H. Knoll

Keyword(s):

Green Algae ◽

South China ◽

Brown Algae ◽

Body Plan ◽

Early Cambrian ◽

Burgess Shale ◽

New Materials ◽

Exceptional Preservation ◽

Animal Remains ◽

Late Neoproterozoic

Carbonaceous compression fossils in shales of the uppermost Doushantuo Formation (ca. 555-590 Ma) at Miaohe in the Yangtze Gorges area provide a rare Burgess-Shale-type taphonomic window on terminal Proterozoic biology. More than 100 macrofossil species have been described from Miaohe shales, but in an examination of published and new materials, we recognize only about twenty distinct taxa, including Aggregatosphaera miaoheensis new gen. and sp. Most of these fossils can be interpreted unambiguously as colonial prokaryotes or multicellular algae. Phylogenetically derived coenocytic green algae appear to be present, as do regularly bifurcating thalli comparable to red and brown algae. At least five species have been interpreted as metazoans by previous workers. Of these, Protoconites minor and Calyptrina striata most closely resemble animal remains; either or both could be the organic sheaths of cnidarian scyphopolyps, although an algal origin cannot be ruled out for P. minor. Despite exceptional preservation, the Miaohe assemblage contains no macroscopic fossils that can be interpreted with confidence as bilaterian animals. In combination with other late Neoproterozoic and Early Cambrian body fossils and trace fossils, the Doushantuo assemblage supports the view that body-plan diversification within bilaterian phyla was largely a Cambrian event.

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A New Platy-armored Worm from the Early Cambrian Chengjiang Lagerstätte, South China

Acta Geologica Sinica - English Edition ◽

10.1111/j.1755-6724.2003.tb00103.x ◽

2010 ◽

Vol 77 (1) ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

HAN Jian ◽

ZHANG Xingliang ◽

ZHANG Zhifei ◽

SHU Degan

Keyword(s):

South China ◽

Early Cambrian ◽

Chengjiang Lagerstätte

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Sedimentary geochemistry of the Early Cambrian Niutitang Formation to reconstruct the palaeo‐depositional environments and to evaluate the organic matter enrichment mechanism from the Yangtze Block, South China

Geological Journal ◽

10.1002/gj.4304 ◽

2021 ◽

Author(s):

Rizwan Sarwar Awan ◽

Chenglin Liu ◽

Ashar Khan ◽

Qibiao Zang ◽

Yuping Wu ◽

...

Keyword(s):

Organic Matter ◽

South China ◽

Depositional Environments ◽

Early Cambrian ◽

Yangtze Block ◽

Sedimentary Geochemistry ◽

Niutitang Formation

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NUMERICAL ANALYSES OF LEAF AND FRUIT EXTERNAL MORPHOLOGY IN Moringa oleifera LAM

Jurnal Teknologi ◽

10.11113/jt.v77.6368 ◽

2015 ◽

Vol 77 (13) ◽

Author(s):

Daniel Andrawus Zhigila ◽

Sulaiman Mohammed ◽

Felix Ayodele Oladele ◽

Fatima B. J. Sawa

Keyword(s):

Moringa Oleifera ◽

Crop Improvement ◽

Morphological Diversity ◽

External Morphology ◽

Numerical Analyses ◽

Qualitative And Quantitative ◽

Quantitative Characters ◽

Diversity Assessment ◽

Wide Range ◽

Improvement Programme

The wide range of uses of Moringa oleifera in recent time has witnessed increasing demand of its foliar and seed products in nutritional, medical and ecological applications. The upsurge of demand for these products needs to be balanced with new varieties of improved performance to meet the supply chain. To achieve this, morphological diversity assessment is prerequisite for future crop improvement programme. Therefore, numerical analyses of the external morphology of leaf and fruit of thirty accessions of Moringa oleifera were assessed. The study was carried out on both qualitative and quantitative characters to assess the diversity at morphological level to establish the phenetic relationships and the delimitation of accessions. Relationship studies showed considerable correlation between the leaf and fruits characters that produced clear and reproducible threats and were selected for diversity study. Numerical analysis of the qualitative and quantitative characters clustered the accessions into five groups – operational taxonomic units (OTUs) 1, 2, 3, 4, 5, 7, 9, 10, 11, 12, 13, 14, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30 were clustered in group one; OTUs 6 and 8 were clustered in group two and three respectively; OTUs 15 and 16 in group four and OUT 23 in group five cluster membership. Principal Component Analysis was carried out to augment the Cluster Analysis which showed large morphological diversity existing in accessions of Moringa oleifera hence, infraspecific classification is hereby proposed. These analysis particularly traits related to leaf and fruits yield can also be utilised for crop improvement programme.

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Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections

Life ◽

10.3390/life12010062 ◽

2022 ◽

Vol 12 (1) ◽

pp. 62

Author(s):

Harri Hemilä ◽

Elizabeth Chalker

Keyword(s):

Clinical Trials ◽

Vitamin C ◽

Common Cold ◽

Evidence Based Medicine ◽

Evidence Based ◽

The Third ◽

Nutritional Recommendations ◽

Mainstream Medicine ◽

The Common ◽

Based Medicine

Evidence has shown unambiguously that, in certain contexts, vitamin C is effective against the common cold. However, in mainstream medicine, the views on vitamin C and infections have been determined by eminence-based medicine rather than evidence-based medicine. The rejection of the demonstrated benefits of vitamin C is largely explained by three papers published in 1975—two published in JAMA and one in the American Journal of Medicine—all of which have been standard citations in textbooks of medicine and nutrition and in nutritional recommendations. Two of the papers were authored by Thomas Chalmers, an influential expert in clinical trials, and the third was authored by Paul Meier, a famous medical statistician. In this paper, we summarize several flaws in the three papers. In addition, we describe problems with two recent randomized trial reports published in JAMA which were presented in a way that misled readers. We also discuss shortcomings in three recent JAMA editorials on vitamin C. While most of our examples are from JAMA, it is not the only journal with apparent bias against vitamin C, but it illustrates the general views in mainstream medicine. We also consider potential explanations for the widespread bias against vitamin C.

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N.V. Gogol’s Works and Censorship

Literary Fact ◽

10.22455/2541-8297-2021-20-238-256 ◽

2021 ◽

pp. 238-256

Author(s):

Igor A. Vinogradov

Keyword(s):

Literary Criticism ◽

Good Reason ◽

Evidence Based ◽

Previous Period ◽

Analytical Review ◽

Negative Role ◽

The Common ◽

The Government ◽

First Time

For the first time, an analytical review of all, without exception, censorship stories of N.V. Gogol’s works is presented. An objective picture of Gogol's relationship with the censorship is being recreated. The findings of the study allow, with good reason, to judge about the interference of censors in the writer's works in a fundamentally different way, in comparison with the ideas offered by literary criticism of the previous period without solid evidence. Based on a thorough analysis, involving numerous archival sources, the common, stereotypical opinions about the extremely negative role of censorship in Gogol’s fate are being revised. The most significant negative result among all censorship interventions in Gogol's works was the activity of the censor of Westernizing views, opposed to the government, a professor at St. Petersburg University, A.V. Nikitenko. It is the numerous reductions of Nikitenko, И.А. Виноградов. Произведения Н .В. Гоголя и цензура 255 a friend of V.G. Belinsky, in Gogol's religious and patriotic book “Selected Passages from Correspondence with Friends” that the writer called “censorship murder”. No less significant was the intervention of the liberal censor in the texts of “Dead Souls”, “Theatrical Travel after the Presentation of a New Comedy” and other works of the writer. It is concluded that, with the exception of this “intrigue” against Gogol by the censor Nikitenko, on the whole Gogol's texts encountered relatively insignificant difficulties in censorship.

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Chapter 9: Pathways Toward Desirable Futures

Journal of Teaching in Physical Education ◽

10.1123/jtpe.2020-0247 ◽

2021 ◽

pp. 1-8

Author(s):

Murray F. Mitchell ◽

Hal A. Lawson ◽

Hans van der Mars ◽

Phillip Ward

Keyword(s):

Physical Education ◽

Common Good ◽

Evidence Based ◽

Societal Change ◽

Special Issue ◽

Distinctive Features ◽

The Common ◽

Education Profession ◽

Education Model ◽

Fierce Competition

This special issue was designed to facilitate futures-oriented planning, focused on identical, similar, and unique practice and policy priorities. Formal planning aimed at desirable futures is a practical necessity for every helping profession because rapid, sometimes dramatic, societal change continues nonstop. Like all futures-oriented analyses, ours is unavoidably selective. Selectivity, once recognized, is a strength because readers are not asked to view the main claims and recommendations as a final authority. Selective research and scholarship focused on the creation and safeguarding of desirable futures has generative propensities that can provide the impetus for subsequent proposals aimed at the common good. In this chapter, the authors offer an integrative summary of the work in this special issue. Our summary invites readers’ special attention to distinctive features in their respective home contexts. This perspective stands in stark contrast to 20th Century models often described as “one best system” and “one ideal physical education model.” Justifiable variability—where “justifiable” means evidence-based and harmonized values—is the new norm for the 21st Century. The authors conclude that the physical education profession will benefit to the extent that it adopts the theme offered in this special issue. Unity founded on diversity—an idea whose time has come in a field known for fierce competition over curricula and programs.

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An Evidence-Based Health Information System Theory

Health Information Systems ◽

10.4018/978-1-60566-988-5.ch127 ◽

2011 ◽

pp. 1994-2011

Author(s):

Daniel Carbone

Keyword(s):

Information Systems ◽

Systems Theory ◽

Health Information ◽

Health Sector ◽

Health Information System ◽

Building Blocks ◽

Evidence Based ◽

Supporting Evidence ◽

The Common ◽

Is Theory

The aim of this chapter is to bridge the gap between what is known about IS theory and the specifics characteristics of health to develop an evidence based health information systems theory. An initial background first sets the significance for the need to have a solid information systems theory in health and then argues that neither the information systems literature nor the health sector have been able to provide any satisfactory pathway to facilitate the adoption of information systems in health settings. The chapter further continues by reviewing the common pathway to develop information systems theory and the knowledge foundations used in the process, and then proceeds to highlight how this theory was developed. Subsequently, the building blocks (constructs, premises, supporting evidence and conclusions) that underpins the constructs and a brief explanation of the relationships between them is included. A discussion and limitation section is then followed by a conclusion.

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Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan

BMC Evolutionary Biology ◽

10.1186/s12862-020-01720-6 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Richard J. Howard ◽

Gregory D. Edgecombe ◽

Xiaomei Shi ◽

Xianguang Hou ◽

Xiaoya Ma

Keyword(s):

Feeding Strategy ◽

Phylogenetic Analyses ◽

Morphological Diversity ◽

Early Cambrian ◽

Ancestral State ◽

Crown Group ◽

Stem Group ◽

Chengjiang Biota ◽

Fossil Records ◽

Experimental Decay

Abstract Background Ecdysozoa are the moulting protostomes, including arthropods, tardigrades, and nematodes. Both the molecular and fossil records indicate that Ecdysozoa is an ancient group originating in the terminal Proterozoic, and exceptional fossil biotas show their dominance and diversity at the beginning of the Phanerozoic. However, the nature of the ecdysozoan common ancestor has been difficult to ascertain due to the extreme morphological diversity of extant Ecdysozoa, and the lack of early diverging taxa in ancient fossil biotas. Results Here we re-describe Acosmia maotiania from the early Cambrian Chengjiang Biota of Yunnan Province, China and assign it to stem group Ecdysozoa. Acosmia features a two-part body, with an anterior proboscis bearing a terminal mouth and muscular pharynx, and a posterior annulated trunk with a through gut. Morphological phylogenetic analyses of the protostomes using parsimony, maximum likelihood and Bayesian inference, with coding informed by published experimental decay studies, each placed Acosmia as sister taxon to Cycloneuralia + Panarthropoda—i.e. stem group Ecdysozoa. Ancestral state probabilities were calculated for key ecdysozoan nodes, in order to test characters inferred from fossils to be ancestral for Ecdysozoa. Results support an ancestor of crown group ecdysozoans sharing an annulated vermiform body with a terminal mouth like Acosmia, but also possessing the pharyngeal armature and circumoral structures characteristic of Cambrian cycloneuralians and lobopodians. Conclusions Acosmia is the first taxon placed in the ecdysozoan stem group and provides a constraint to test hypotheses on the early evolution of Ecdysozoa. Our study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy (e.g. predation), may have characterised the origin and radiation of crown group ecdysozoans from Acosmia-like ancestors.

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