Article
Geosciences, Multidisciplinary
Xiaoqiang Pan, Liang Xiong, Qiaokun Dai, Jinzhou Luo, Ziwei Liu, Tong Wang, Hong Hua
Summary: This article reports the discovery of a new assemblage of helically coiled microfossils from the Maidiping Formation in southern Sichuan Province, China, during the Ediacaran-Cambrian transition. The fossil assemblage includes several species of Obruchevella, which exhibit a variety of morphologies and show affinities with modern helical cyanobacteria. These fossils provide important insights into the evolution of early ecosystems and metazoan radiation during this time period.
PRECAMBRIAN RESEARCH
(2022)
Article
Multidisciplinary Sciences
Zhengpeng Chen, Yuanlong Zhao, Xinglian Yang, Jorge Esteve, Xiong Liu, Shengguang Chen
Summary: The evolution process can be reconstructed by tracking the changes in the dynamic characters of life cycles. Trilobite evolutionary patterns are studied using related trilobites from the Cambrian of South China, providing additional information due to previous incomplete fossil records. The study discusses the ontogeny of Balangia and Duyunaspis, revealing a directional evolution in their exoskeletal morphology. Based on the evolutionary changes observed, it is speculated that Duyunaspis evolved from Balangia instead of the previous assumption of Balangia evolving from Duyunaspis. The findings also support the inference made by the phylogenetic tree.
Article
Multidisciplinary Sciences
Russell D. C. Bicknell, Patrick M. Smith
Summary: Injured trilobite specimens provide insights into the predator-prey systems of Paleozoic era, specifically how an extinct group of arthropods responded to traumatic experiences such as failed predation. The study presents new examples of injured trilobites and discusses their possible origins and predators.
Article
Geosciences, Multidisciplinary
Yifan Wang, Jorge Esteve, Xinglian Yang, Rongxing Yu, Dezhi Wang
Summary: This study reports on two specimens of eodiscid trilobites, which show a Somersault configuration using facial and rostral sutures to create an anterior exuvial gape. This discovery is important for understanding trilobite moulting behavior during the Cambrian period.
GEOLOGICAL MAGAZINE
(2023)
Article
Geology
Leslie A. Melim, Sebastien R. Mure-Ravaud, Thomas A. Hegna, Brian J. Bellott, Rudy Lerosey-Aubril
Summary: This study reports on silicified trilobite sclerites with associated silicified biofilm from the Cambrian Weeks Formation, Utah (USA), providing support for the role of microbial biofilms in silicification. The presence of carbon-rich threads, ribbons, and mats coating the sclerites and silica-cemented matrix is interpreted as silicified biofilm. The study also suggests that silica precipitation continued into the surrounding matrix following bacterial decay, supporting the idea that bacterially mediated decay is key to the silicification of carbonate bioclasts.
Article
Multidisciplinary Sciences
Yu Liu, Gregory D. Edgecombe, Michel Schmidt, Andrew D. Bond, Roland R. Melzer, Dayou Zhai, Huijuan Mai, Maoyin Zhang, Xianguang Hou
Summary: This study reveals the presence of exites at the base of most appendages in the Cambrian arthropod Leanchoilia, suggesting a deeper origin for exites in arthropod phylogeny. The discovery of a previously undetected exite at the base of appendages sheds new light on the evolutionary history of arthropods.
NATURE COMMUNICATIONS
(2021)
Article
Biology
Russell D. C. Bicknell, James D. Holmes, Gregory D. Edgecombe, Sarah R. Losso, Javier Ortega-Hernandez, Stephen Wroe, John R. Paterson
Summary: The study suggests that Cambrian euarthropods with transversely elongate protopodites bearing short, robust gnathobasic spines were likely durophages, while taxa with shorter protopodites armed with long spines were more likely restricted to a soft food diet.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2021)
Article
Geography, Physical
M. Gabriela Mangano, Beatriz G. Waisfeld, Luis A. Buatois, N. Emilio Vaccari, Diego F. Munoz
Summary: Estuarine deposits in Argentina contain fossils that help understand the early colonization of marginal-marine environments and the effects of evolutionary and environmental factors.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2023)
Article
Multidisciplinary Sciences
Zhixin Sun, Fangchen Zhao, Han Zeng, Cui Luo, Heyo Van Iten, Maoyan Zhu
Summary: The discovery of the Linyi Lagerstatte in North China provides new insights into the Cambrian explosion of animals. This new lagerstatte contains well-preserved soft-bodied fossils and shows similarities with other known lagerstatten, offering a promising opportunity to study the Cambrian marine faunas.
NATIONAL SCIENCE REVIEW
(2022)
Article
Geography, Physical
Russell D. C. Bicknell, James D. Holmes, Stephen Pates, Diego C. Garcia-Bellido, John R. Paterson
Summary: The Cambrian explosion marked the rapid development of complex marine ecosystems on Earth due to predator-prey interactions, which led to the evolution of biomineralised exoskeletons and shell-crushing predators. Injured trilobite specimens from Kangaroo Island, South Australia show evidence of attacks mostly on the posterior thorax, suggesting predators attacked from behind. Larger individuals were more likely to survive attacks and exhibit healed injuries, indicating smaller individuals were likely consumed during an attack.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Russell D. C. Bicknell, James D. Holmes, Diego C. Garcia-Bellido, John R. Paterson
Summary: Malformed specimens of the ellipsocephaloid trilobite Estaingia bilobata from the Emu Bay Shale Konservat-Lagerstatte are reported, with most of the malformed specimens clustering among larger individuals. This suggests that larger forms may have successfully escaped predation attempts or represent individuals with old injuries that have healed through subsequent moulting events. The presence of mangled exoskeletons indicates predation on E. bilobata, highlighting its role in the local ecosystem.
GEOLOGICAL MAGAZINE
(2023)
Article
Ecology
Jun Zhao, Yujing Li, Paul A. Selden
Summary: This passage describes the diversity and importance of sessile epibenthos in the energy flow process of the Cambrian marine ecosystem. Based on new specimens, two new representatives of the group with characteristics of cnidarians and bryozoans are described. If confirmed, these new findings can contribute to understanding the origin and early evolution of these two phyla. The discovery of more sessile epibenthos suggests a greater diversity in the benthic ecosystem of the Guanshan biota (Cambrian Series 2, Stage 4) than previously believed.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2023)
Article
Geography, Physical
Daniela S. Monti, Viviana A. Confalonieri, M. Franco Tortello
Summary: This study investigates the biogeographic histories of two cosmopolitan groups of Olenida, Hypermecaspididae and Parabolinella (Olenidae). Different biogeographical models were compared, and the results suggest that jump dispersal was an important speciation strategy for both groups. Vicariance was found to be unimportant. The dispersal patterns of Parabolinella were influenced by ocean currents, while those of Hypermecaspididae were not. Island hopping and creeping were the main dispersal mechanisms for both groups. The western margin of Gondwana played a significant role as a dispersal center during the Furongian and Early Ordovician.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Guangyou Zhu, Tingting Li, Kun Zhao, Chao Li, Meng Cheng, Weiyan Chen, Huihui Yan, Zhiyao Zhang, Thomas J. Algeo
Summary: This study reports on the Mo isotopic compositions and iron speciation data of black shales from the Tarim block during the early Cambrian, providing insights into the paleoenvironment and oxygenation conditions in the ancient seawater.
GEOLOGICAL SOCIETY OF AMERICA BULLETIN
(2022)
Article
Paleontology
John R. Foster
Summary: The restudy of dolichometopid trilobites in the Cadiz Formation in California, USA, and other formations in western North America reveals that there are only two species present in the Cadiz Formation. Additionally, qualitative characters used in the past for genus separation are found to be continuously variable, making them unreliable for species assignment.
PALAEONTOLOGIA ELECTRONICA
(2022)
