Late Cryogenian-Ediacaran history of the Arabian-Nubian Shield: A review of depositional, plutonic, structural, and tectonic events in the closing stages of the northern East African Orogen

Die Zugehörigkeit und Richtigkeit der Etiquette zu dem Fossil steht durch den petrographischen Charakter des feinen grauen Schieferthones mit vielen wohlerhaltenen Pflanzenresten, die das dortige Steinkohlengebirge bezeichnen , ausser allem Zweifel. Der Finder, der Einsender, sowie die Zeit des Fundes konnten weder durch die Inventarien noch durch die Handschrift des Bestimmers von dem Fossile ermittelt werden. Zwei genau auf einander passende Schieferthonplatten enthalten den Abdruck und den Gegendruck des wohl conservirten und scharf abgedrückten Fossils. Ein drittes Stück Schieferthon desselben Fundortes zeigt noch ein Bruchstück desselben Thieres, zum Beweise, dass es nicht so gar selten in diesen Schichten gewesen zu sein braucht. Der Gegenstand unserer Betrachtung ist der Abdruck einer rechten Schalenhälfte eines bivalvenartigen Thieres. Eine nähere Betrachtung desselben zeigt bald die Unrichtigkeit der obigen alten Bestimmung als Posidonomya oder Posidonia; denn der ganz an dem vorderen Ende des allerdings geraden Dorsalrandes (vergl. Taf. XVI., Fig. 1) gelegene Wirbel, um den herum die concentrische Runzelung sich über die ganze Valve zieht, widerspricht vollständig dem von H. Brosn auf-

Zeitschrift der Deutschen Geologischen Gesellschaft

Simple multicellularity has evolved numerous times within the Eukarya, but complex multicellular organisms belong to only six clades: animals, embryophytic land plants, florideophyte red algae, laminarialean brown algae, and two groups of fungi. Phylogeny and genomics suggest a generalized trajectory for the evolution of complex multicellularity, beginning with the co-optation of existing genes for adhesion. Molecular channels to facilitate cell-cell transfer of nutrients and signaling molecules appear to be critical, as this trait occurs in all complex multicellular organisms but few others. Proliferation of gene families for transcription factors and cell signals accompany the key functional innovation of complex multicellular clades: differentiated cells and tissues for the bulk transport of oxygen, nutrients, and molecular signals that enable organisms to circumvent the physical limitations of diffusion. The fossil records of animals and plants document key stages of this trajectory.

The Multiple Origins of Complex Multicellularity

Uranium and molybdenum isotope evidence for an episode of widespread ocean oxygenation during the late Ediacaran Period

The end of the Ediacara biota: Extinction, biotic replacement, or Cheshire Cat?

Ediacaran fronds at Spaniard's Bay on the Avalon Peninsula of Newfoundland exhibit exquisite, three-dimensional preservation with morphological features less than 0.05 mm in width visible on the best preserved specimens. Most of the nearly 100 specimens are juvenile rangeomorphs, an extinct Ediacaran clade that numerically dominated the early evolution of complex multicellular life. Spaniard's Bay rangeomorphs are characterized by cm-scale architectural elements exhibiting self-similar branching over several fractal scales that were used as modules in construction of larger structures. Four taxa of rangeomorph fronds are present – Avalofractus abaculus n. gen. et sp., Beothukis mistakensis Brasier and Antcliffe, Trepassia wardae (Narbonne and Gehling), and Charnia cf. C. masoni Ford. All of these taxa exhibit an alternate array of primary rangeomorph branches that pass off a central stalk or furrow that marks the midline of the petalodium. Avalofractus is remarkably self similar over at least four fractal scales, with each scale represented by double-sided rangeomorph elements that were constrained only at their attachment point with the higher-order branch and thus were free to rotate and pivot relative to other branches. Beothukis is similar in organization, but its primary branches show only one side of a typical rangeomorph element, probably due to longitudinal branch folding, and the position of the individual branches was moderately constrained. Trepassia shows only single-sided branches with both primary and secondary branches emanating from a central stalk or furrow; primary branches were capable of minor pivoting as reflected in bundles of secondary branches. Charnia shows only single-sided primary branches that branch from a zigzag central furrow and that were firmly constrained relative to each. This sequence provides a developmental linkage between Rangea-type and Charnia-type rangeomorphs. Avalonian assemblages show a wide array of rangeomorph constructions, but later Ediacaran assemblages contain a lower diversity of rangeomorphs represented mainly by well-constrained forms.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000043201

Reconstructing a Lost World: Ediacaran Rangeomorphs from Spaniard's Bay, Newfoundland

A second tribosphenic mammal from the Mesozoic of Australia

A diverse assemblage of macroscopic algal fossils was recently discovered in the lower part of the Nama Group, Kliphoek Member of the Dabis Formation (Late Ediacaran of Namibia). This assemblage consists of three distinct taxa that have been previously reported from Neoproterozoic successions of European Russia and South China: Glomulus filamentum Steiner, 1994; Eoholinia fruticulosa A. Istchenko, 1989; Tyrasotaenia podolica Gnilovskaya, 1971; a fourth taxon may be related to Kanilovia sp., but also may have other affinities. This assemblage suggests that the best correlation of the Namibian sediments bearing this new algal assemblage would be with with the Upper Kotlin (uppermost Neoproterozoic) deposits of the Russian Platform.

Discovery of the first macroscopic algal assemblage in the Terminal Proterozoic of Namibia, southwest Africa

Reconnaissance for an Ediacaran fauna, Kingdom of Saudi Arabia

In search of the kingdom's Ediacarans: The first genuine Metazoans (mcaroscopic body and trace fossils) from the Neoproterozoic Jibalah group (Vendian/Ediacaran) on the Arabian Shield

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Peter Trusler

Author Tools

Chat about Author