Results 11 to 20 of about 166 (116)

The evolution of reproduction in Ediacaran-Cambrian metazoans. [PDF]

Biol Rev Camb Philos Soc
ABSTRACT The evolution of reproductive style is a fundamental aspect of metazoan life history but has not been explored holistically through the Ediacaran–Cambrian rise of metazoans. Recent molecular clock analyses based on only unequivocal metazoan fossil calibrations suggest that Porifera were present by at least 590 million years ago (Ma), all major
Wood RA, Droser ML.
europepmc   +2 more sources

Localized and Transient Oxygenation of Shallow Oceans of Southwestern Laurentia at the Ediacaran-Cambrian Boundary. [PDF]

Geobiology
ABSTRACT The Ediacaran–Cambrian boundary, which precedes one of the most significant biotic diversification events in Earth's history, is associated with a global negative carbon isotope excursion termed the BAsal Cambrian carbon isotope Excursion (BACE).
Chanchai W, Nelson LL, Smith EF, Hardisty DS, Lonsdale MC, Burke JE, Lau KV.   +6 more
europepmc   +2 more sources

Doushantuo-Pertatataka—Like Acritarchs From the Late Ediacaran Bocaina Formation (Corumbá Group, Brazil)

Frontiers in Earth Science, 2021
Acritarchs, a polyphyletic group of acid-resistant organic-walled microfossils, dominate the eukaryotic microfossil record in the Proterozoic (2500–541 Ma) yet exhibit significant reduction in diversity and size at the transition to the Phanerozoic (541 ...
L. Morais, L. Morais, T. R. Fairchild, B. T. Freitas, I. D. Rudnitzki, E. P. Silva, D. Lahr, A. C. Moreira, E. A. Abrahão Filho, J. M. Leme, R. I. F. Trindade   +10 more
doaj   +1 more source

Three‐dimensional reconstruction, taphonomic and petrological data suggest that the oldest record of bioturbation is a body fossil coquina

Papers in Palaeontology, Volume 9, Issue 6, November/December 2023., 2023
Abstract Fossil material assigned to Nenoxites from the late Ediacaran Khatyspyt Formation of Arctic Siberia (550–544 Ma) has been presented as evidence for bioturbation prior to the basal Cambrian boundary. However, that ichnological interpretation has been challenged, and descriptions of similar material from other global localities support a body ...
Christos Psarras, Philip C.J. Donoghue, Russell J. Garwood, Dmitriy V. Grazhdankin, Luke A. Parry, Vladimir I. Rogov, Alexander G. Liu   +6 more
wiley   +1 more source

Unmixing of Magnetic Hysteresis Loops Through a Modified Gamma‐Cauchy Exponential Model

Geochemistry, Geophysics, Geosystems, Volume 24, Issue 8, August 2023., 2023
Abstract Quantifying the contributions of distinct mineral populations in bulk magnetic experiments greatly enhances the analysis of environmental and rock magnetism studies. Here, we develop a new method of parametric unmixing of susceptibility components in hysteresis loops.
U. D. Bellon, R. I. F. Trindade, W. Williams   +2 more
wiley   +1 more source

New and revised small shelly fossil record from the lower Cambrian of northern Iran

Papers in Palaeontology, Volume 7, Issue 4, Page 2141-2181, November 2021., 2021
Abstract Small shelly fossils (SSFs) are highly informative of the ‘Cambrian explosion’. Their palaeobiodiversity has been documented from lower Cambrian deposits worldwide but it remains elusive in areas such as Iran, despite this region occupying a critical position on the north‐western Gondwana margin during the early Cambrian. This new study of the
Léa Devaere, Dieter Korn, Abbas Ghaderi, Ulrich Struck, Alireza K. Bavandpur, Javier Álvaro   +5 more
wiley   +1 more source

Ediacaran metazoan fossil record from South America and its implications in the studies about origin and complexification of animal life [PDF]

Geologia USP. Série Científica, 2013
The Ediacaran Period marks the first appearance of complex macroscopic organisms in the fossil record. Current evidence indicates that Ediacara biota is composed of animals, groups of extinct giant protists, algae and other organisms without proven ...
Bruno Becker Kerber, Ana Lucia Zucatti da Rosa, Sandra Garcia Gabas, Juliana de Moraes Leme, Mírian Liza Alves Forancelli Pacheco   +4 more
doaj   +1 more source

First occurrence of Cloudina carinata Cortijo et al., 2010 in South America, Tamengo Formation, Corumbá Group, upper Ediacaran of Midwestern

Estudios Geologicos, 2019
It is herein presented the unprecedented occurrence of Cloudina carinata Cortijo et al., 2010 in the American continent. This new occurrence expanded the geographic distribution of this species, until now reported from sections in Spain and Siberia.
R. R. Adôrno, D. H.G. Walde, B. D. Erdtmann, M. Denezine, I. Cortijo, D. A. Do Carmo, M. Giorgioni, M. E.A.F. Ramos, G. Fazio   +8 more
doaj   +1 more source

Una biota transicional Ediacárica–Cámbrica en el anticlinal de Abenójar (Macizo Ibérico, España)

Estudios Geologicos, 2018
Se describe una secuencia conteniendo una biota transicional ediacárica–cámbrica, en el valle del arroyo de las Navezuelas, anticlinal de Abenójar (Grupo Ibor, Zona Centroibérica, España).
J. Simón
doaj   +1 more source

New Facies Model and Carbon Isotope Stratigraphy for an Ediacaran Carbonate Platform From South America (Tamengo Formation—Corumbá Group, SW Brazil)

Frontiers in Earth Science, 2022
The Ediacaran is a period characterized by the diversification of early animals and extensive neritic carbonate deposits. These deposits are still not well understood in terms of facies and carbon isotope composition (δ13C). In this study we focus on the
Maria E. A. F. Ramos, Martino Giorgioni, Detlef H. G. Walde, Dermeval A. do Carmo, Gabriella Fazio, Lucieth C. Vieira, Matheus Denezine, Roberto V. Santos, Rodrigo R. Adôrno, Rodrigo R. Adôrno, Lucas Lage Guida   +10 more
doaj   +1 more source