Article
Paleontology
James D. Holmes, John R. Paterson, Diego C. Garcia-Bellido
Summary: Trilobites, particularly the ellipsocephaloid Estaingia bilobata, play an important role in studying early animal evolution and developmental processes. This study provides insights into the post-embryonic ontogenetic series of E. bilobata, with new information on growth patterns and morphological features. The findings further support the phylogenetic relationships between the Estaingiidae, Ellipsocephalidae, and Xystriduridae.
PAPERS IN PALAEONTOLOGY
(2021)
Article
Paleontology
Qiao Zhang, Tao Dai, Xing-liang Zhang, Shan-chi Peng
Summary: The study presents the ontogenetic sequence of Bathynotus kueichouensis, an early Cambrian trilobite, based on articulated specimens from Guizhou, China. The variation in trunk segment morphology between different thoracic regions suggests a wide variation in the body regionalization of B. kueichouensis. The study also reveals a significant size variation in long pleural spines during the developmental stages of the trilobite, offering insights into the evolutionary path of trilobite body structures. The ontogenetic strategy of B. kueichouensis is similar to other redlichioid representatives, indicating a balanced rate of segment expression and liberation.
Article
Biology
Jorge Esteve, Nigel C. C. Hughes
Summary: Three-dimensional models show how the exoskeletal enrolment mechanics changed during the development of the 429-million-year-old trilobite Aulacopleura koninckii. The researchers found that the style of enrolment shifted from sphaeroidal to non-sphaeoridal as the trilobite matured and needed to maintain effective exoskeletal shielding. This change in enrolment accommodated the species' variation in mature trunk segments and suggests adaptation to a physically challenging, low oxygen environment.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2023)
Article
Biodiversity Conservation
Tao Dai, Nigel C. Hughes, Xingliang Zhang, Giuseppe Fusco
Summary: Multiple specimens of the oryctocarine trilobite Oryctocarella duyunensis, around 514 million years old, were found in a short stratigraphic interval near Bulin in western Hunan, China. These specimens showed determinate growth in trilobites, with three different varieties of terminal stages observed in the sample. The growth pattern seen in the Bulin assemblage slightly differs from that in the same species from two other localities, suggesting microevolutionary variation in developmental patterns among these collections.
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
Biology
Melanie J. Hopkins, Rebecca To
Summary: This study analyzes over 1500 species of trilobites and reveals long-term shifts in segment number and allocation, which cannot be explained by taxonomic turnover or trends in functionally relevant behavior.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Jin-bo Hou, Nigel C. Hughes, Melanie J. Hopkins
Summary: Efficient extraction of oxygen from ambient waters was crucial for the early arthropods. They maximized gill surface area to enhance oxygen uptake, but this also led to gill contamination due to exposure to the external environment. The presence of setae on the walking legs of Olenoides serratus and on the gill shaft of Triarthrus eatoni suggests that grooming was used to remove particles trapped among the gill filaments, similar to modern crustaceans.
GEOLOGICAL MAGAZINE
(2023)
Article
Biology
James D. Holmes, John R. Paterson, Diego C. Garcia-Bellido
Summary: Analyzing the growth dynamics of trilobites revealed significant changes in post-embryonic axial growth at different developmental stages, which are closely related to sexual maturity in extant euarthropods. The observed body segmentation patterns in trilobites suggest a complex series of changing growth controls, indicating a more complex development than previously thought.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2021)
Article
Paleontology
Stephen R. Westrop, Alyce A. Dengler
Summary: A new fossil species of Catillicephala, C. cifellii, is discovered from the mid-Cambrian margin of Laurentian North America. It is among the oldest representatives of the genus, dating back to the early Guzhangian period.
ACTA PALAEONTOLOGICA POLONICA
(2022)
Article
Paleontology
Luis Collantes, Eduardo Mayoral, Eladio Linan, Rodolfo Gozalo
Summary: New atopid trilobites from the early Cambrian Cumbres beds and Herrerias shale in northern Huelva Province, Andalusia, Spain are described and dated as middle-late Marianian (Cambrian Series 2, Stage 4). The study also recognizes the Laurentian species Pseudatops reticulatus for the first time in the Mediterranean subprovince. The associated trilobite assemblage in this study suggests an age close to the base of Cambrian Stage 4.
JOURNAL OF PALEONTOLOGY
(2021)
Article
Paleontology
Shelly J. Wernette, Nigel C. Hughes, Paul M. Myrow, Apsorn Sardsud
Summary: The Tuff-bearing strata on Ko Tarutao island in southern Thailand are significant for their rich trilobite fauna, which provides insights into global biostratigraphy, peri-Gondwanan paleogeography, and evolutionary shifts.
PAPERS IN PALAEONTOLOGY
(2023)
Editorial Material
Multidisciplinary Sciences
Graham E. Budd, Georg Mayer, Ralf Janssen, B. Joakim Eriksson
Summary: Strausfeld et al. claim that fossilized nervous tissue from the Cambrian period supports the idea that the ancestral panarthropod brain was tripartite and unsegmented. However, we argue that this conclusion is not supported by evidence, and developmental data from living onychophorans contradict it.
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
Cong Liu, Dongjing Fu, Xingliang Zhang
Summary: This study describes the postembryonic development of a Waptiid arthropod from the early Cambrian Chengjiang biota in South China, revealing a complex dynamic pattern of development and a three-step process of segmentogenesis. These findings are important for understanding the rapid diversification of arthropods in the early Cambrian.
Article
Paleontology
Melanie J. Hopkins
Summary: This study utilizes the material of the trilobite Elrathia kingii to investigate its shape change and growth rates during development, comparing it with the Silurian trilobite Aulacopleura koninckii. Despite some differences in characteristics, both species exhibit similar maximum body lengths.
PAPERS IN PALAEONTOLOGY
(2021)
Article
Paleontology
Tao Dai, Nigel C. Hughes, Xingliang Zhang, Shanchi Peng
Summary: Abundant articulated specimens of the oryctocarine trilobite Oryctocarella duyunensis from the lower Cambrian Balang Formation in western Hunan Province, South China, allow the description of all meraspid degrees. The study shows progressive and gradual change in overall form during meraspid growth, with variation in the number of pygidial segments. A model based on degree-based ontogenetic staging is more likely to explain the growth pattern observed, compared to a model based on the number of thoracic and pygidial segments.
JOURNAL OF PALEONTOLOGY
(2021)
Review
Paleontology
Xingliang Zhang, Degan Shu
Summary: The Cambrian Explosion is a three-phased burst of animal body plans, characterized by changes in population diversity, morphospace exploration, and ecosystem complexity. The high number of stem groups in the early history of animals led to the morphological gaps across phyla that exist today. Despite a broad range of metazoan morphospace occupation in the early Cambrian, the exact causes of the explosion are complex and cannot be attributed to a single factor.
Article
Paleontology
Cong Liu, Dongjing Fu, Xingliang Zhang
Summary: The study reveals that the lightly sclerotized arthropod Chuandianella ovata from the Chengjiang biota reinforced its carapace with phosphatic mineralization. Fossil record indicates that arthropods and ecdysozoans began mineralization in Cambrian Stage 3 (around 521-514 Ma) and exceeded the range of living counterparts in phylogenetic coverage.
Article
Biology
Dongjing Fu, David A. Legg, Allison C. Daley, Graham E. Budd, Yu Wu, Xingliang Zhang
Summary: This study reports a new arthropod species, Erratus sperare, with trunk appendages representing an intermediate stage of biramous limb evolution. The species occupies an early node within the basal region of arthropods and reveals the earliest occurrence of the endopod within Deuteropoda.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2022)
Article
Multidisciplinary Sciences
Cong Liu, Dongjing Fu, Xingliang Zhang
Summary: This study describes the postembryonic development of a Waptiid arthropod from the early Cambrian Chengjiang biota in South China, revealing a complex dynamic pattern of development and a three-step process of segmentogenesis. These findings are important for understanding the rapid diversification of arthropods in the early Cambrian.
Article
Paleontology
Yuan Zhang, Xingliang Zhang
Summary: A new taxon of erect coralline algae was discovered in the Zhenba microfossil assemblage from the Ediacaran Dengying Formation in South China. This finding suggests that early coralline algae were more diverse than previously thought and their morphological diversification and ecological expansion likely occurred in the middle to late Ediacaran.
JOURNAL OF PALEONTOLOGY
(2022)
Article
Multidisciplinary Sciences
Jinhua Li, Peiyu Liu, Nicolas Menguy, Xingliang Zhang, Jian Wang, Karim Benzerara, Lianjun Feng, Lei Sun, Yue Zheng, Fanqi Meng, Lin Gu, Eric Leroy, Jialong Hao, Xuelei Chu, Yongxin Pan
Summary: Biosilicification, the process of forming biological structures composed of silica, is widely distributed among eukaryotes and plays a significant role in global biogeochemical cycles. Recent discoveries of silica transporter genes and silicon accumulation in bacteria suggest that prokaryotes, particularly in ancient times, may also have played a previously unrecognized role in the Si cycle. This study reports the identification of a magnetotactic bacterium that forms intracellular, amorphous silica globules, revealing intracellularly controlled silicification within prokaryotes and its potential influence on the biogeochemical Si cycle during early Earth history.
Article
Geology
Rong-Hao Wei, Liang Duan, Xingliang Zhang, Qing-Ren Meng, Rong-Ruo Zhan, Chu-Xuan Ma, Jing Xu, Yi Shi, Xiao-Yin Zhang
Summary: The basal Cambrian sandstone unit in the North China craton provides insights into the ancient drainage system and its potential linkage with the Gondwana landmass. The detrital zircon age signatures in different sections of the craton show spatial changes and can be categorized into three distinct types, suggesting that the basal Cambrian unit is not part of the sand sheet across the northern margin of Gondwana.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Biology
Hao Yun, Cui Luo, Chao Chang, Luoyang Li, Joachim Reitner, Xingliang Zhang
Summary: Sponge fossils from the Cambrian black shales have been of interest due to their diversity, preservation, and adaptation to inhospitable environments. A new species of hexactinellid sponge, S. tentoriformis, with a unique dendriform body shape, has been discovered in the Qingjiang biota. This body shape represents an adaptation to deep-water, oxygen-deficient conditions, aiding in oxygen utilization and energy conservation.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2022)
Article
Biology
Tao Dai, Xingliang Zhang, Shanchi Peng
Summary: The developmental mode of four redlichiid trilobites is summarized based on well-preserved specimens from Cambrian strata in China and Australia. The study reveals a balanced rate of segment increase and addition during the meraspid phase, explaining the micropygous body patterning in redlichiids. The analysis of size distribution and developmental strategy uncovers a distinct developmental strategy during the redlichiid life cycle.
BIOLOGICAL REVIEWS
(2023)
Article
Evolutionary Biology
Yuan Zhang, Xingliang Zhang, Cong Liu
Summary: Ediacara embryo-like spherical fossils show diverse cell adhesion patterns similar to living animal embryos. Newly discovered specimens are likely developmental precursors of Weng'an counterparts, but also exhibit anatomical features inconsistent with an embryo interpretation.
EVOLUTION & DEVELOPMENT
(2022)
Article
Biology
Luoyang Li, Marissa J. Betts, Hao Yun, Bing Pan, Timothy P. Topper, Guoxiang Li, Xingliang Zhang, Christian B. Skovsted
Summary: This study reveals that the skeletons of early Cambrian mollusks and hyoliths are composed of fibrous microstructures made of calcite, which had not been discovered before. Additionally, it shows that the shells of these early animals were mainly composed of aragonite. This has important implications for understanding the significance of early biomineralization and its relationship with seawater chemistry.
Article
Geosciences, Multidisciplinary
Chao Chang, Wenxuan Hu, Kang-Jun Huang, Zhenfei Wang, Xingliang Zhang
Summary: This article supplements new geochemical evidence for expanded marine euxinia during the Cambrian Age 4 and provides firm support for a causal link between this environment and the extinction event.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Editorial Material
Multidisciplinary Sciences
Kaiyue He, Jianni Liu, Jian Han, Qiang Ou, Ailin Chen, Zhifei Zhang, Dongjing Fu, Hong Hua, Xingliang Zhang, Degan Shu
Summary: In this study, the researchers examined over 8000 specimens of yunnanozoans and found no evidence of cellular cartilage or fibrillin. They also reject the idea that yunnanozoans are stem-group vertebrates based on their ultrastructure and morphology.
Article
Geography, Physical
Sena Kono, Yukio Isozaki, Tomohiko Sato, Xingliang Zhang, Wei Liu
Summary: The detailed lithostratigraphy of the Lower Cambrian in South China was analyzed at the Xiaolantian section in the Chengjiang area, Yunnan, revealing six distinct lithostratigraphic units and one particular terrigenous elastic unit in the middle. These beds were found to have been deposited in shallow marine settings in the Kangdian rift-related basin in western South China. The study also highlighted a significant unit composed of terrigenous elastics in the middle of the Zhongyicun Member, serving as a key bed for lithostratigraphical correlation within the basin.
JOURNAL OF GEOGRAPHY-CHIGAKU ZASSHI
(2021)
