Myrmecomorphy is a phenomenon in which some animals mimic ants morphologically and behaviorally, and belongs to a special kind of anthropomorphic behavior, which is very widely distributed in nature. Myrmecomorphy is a phenomenon in which some animals mimic ants morphologically and behaviorally, and belongs to a special kind of anthropomorphic behavior, which is very widely distributed in nature. Recently, LUO Cihang, a postgraduate student, supervised by Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), collaborated with other scientists from NIGPAS, discovered a new type of alienopterid nymphs from mid-Cretaceous Burmese amber. The discovery indicated that the earliest ant mimicry has already existed in mid-Cretaceous, thereby extending its geological range by approximately 50 million years. This study was published in Earth-Science Reviews on Dec. 30, 2021. More than 2000 living species of insects and spiders, representing 11 different arthropod orders, has evolved at least 30 times among arthropods. However, the fossil record of myrmecomorphy is extremely sparse and researchers know little about its origin and evolution. By using quantitative geometric morphometric analysis, researchers discovered that the body shape of these alienopterid nymphs is very close to sphecomyrmine ant (a kind of extinct ants). Moreover, the shape of the antennae and legs of these alienopterid nymphs and ants are close and the ratios of the antennae and legs to the body length are approximately the same as in some sphecomyrmine ants. "We discovered a new type of alienopterid nymphs and provided new evidence for the early evolution of ant mimicry." WANG says, "we also concluded that these nymphs adults were likely wasp mimics, therefore, we provided the first fossil record of transformational mimicry." In addition, the main progress and significances of this study also confirm wasp mimicry present in Alienopteridae adults and to report the first fossil record of transformational mimicry. Researchers confirmed that thoraco-abdominal waist-like constrictions of some alienopterid adults (adults of those ant mimics) resemble Hymenoptera. Additionally, the strongly shortened forewings of some alienopterid adults closely resemble the tegulae of Hymenoptera and the hind wing structurally similar to hymenopteran wings. Moreover, the body shape and size of some alienopterid adults are similar to some large aculeate Hymenoptera from the same deposit, especially ampulicid wasps. Interestingly, the nymphs and adults of the mid-Cretaceous alienopterid imitate entirely different hymenopteran models, and therefore probably provide the first fossil record of transformational mimicry (mimicking different organisms during their postembryonic development). This research was supported by the Chinese Academy of Sciences, Ministry of Science and Technology of China and National Natural Science Foundation of China. WU Suping from NIGPAS provided technical support for Micro-CT. We also thank Mr. HUANG Yiren and Mr. XIA Fangyuan for providing part of specimens. Reference: Luo Cihang, Beutel R.G., Engel M.S., Liang Kun, Li Liqin, Li Jiahao, Xu Chunpeng, Vr？ansky P., Jarzembowski E.A., Wang Bo, 2021. Life history and evolution of the enigmatic Cretaceous–Eocene Alienopteridae: A critical review. Earth-Science Reviews. https://doi.org/10.1016/j.earscirev.2021.103914 Fig. 1 Representative taxa of Alienopteridae and Umenocoleidae. Fig. 2 Reconstruction drawings of Alienopteridae (Image by LI Jiahao). Fig. 3 Alienopterid nymphs and ants, ants marked with M (Image by NIGPAS). Fig. 4 Ecological reconstruction of Alienopteridae (Image by YANG Dinghua). A: Ecological reconstruction of alienopterid nymphs; the brown insect at left with two cerci are alienopterid nymphs, the other three brown insects are ants. B: Ecological reconstruction of alienopterid adults.
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
During the Late Permian to Early Triassic, benthic marine redox conditions in the Shangsi area varied on both short-term and long-term time scales. This study has scientific implications for revealing the spatial and temporal distribution of anoxic events, and the importance of oceanic anoxia in the end-Permian mass extinction (EPME). During the Late Permian to Early Triassic, benthic marine redox conditions in the Shangsi area varied on both short-term and long-term time scales. This study has scientific implications for revealing the spatial and temporal distribution of anoxic events, and the importance of oceanic anoxia in the end-Permian mass extinction (EPME). About 252 million years ago, more than 81 percent of animal life in the oceans and 89 percent of animal life on land went extinct. Extensive volcanism (the Siberian large igneous province magmatism and felsic volcanism in South China) is the most probable trigger of this life crisis. Oceanic/marine anoxia triggered by volcanisms is the most plausible killing mechanism for the EPME in the marine realm. Although a wealth of studies had supported the latest Permian-Griesbachian extreme anoxia, there is some opposite evidence indicating the occurrence of oxic benthic marine conditions during the Permian-Triassic interval. In addition, it has been reported that the deterioration of the marine environment was probably before the EPME. However, compared to a vast number of studies on the Permian-Triassic interval, only a few studies focusing on the paleo-oxygen levels during the Late Permian have been conducted. Therefore, further work needs to be carried out on the benthic marine redox conditions before and during the EPME. Recently, Dr. ZHENG Quanfeng, Prof. ZHANG Hua, WANG Yue, and CAO Changqun from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NGIPAS), collaborating with researchers from China University of Mining and Technology and Nanjing University, made high-resolution sedimentological and ichnological studies to reveal benthic marine redox conditions and driving mechanisms from Late Permian to the earliest Triassic at Shangsi, South China. This study was published in Earth-Science Reviews on Dec. 20. "We found that high-frequency (centimeter- to decimeter-scale) and secular (meter- to tens of meters-scale) benthic oxygen-level variations were developed at Shangsi", Dr. ZHENG says. The high-frequency variations were mostly local signals generated by transient episodic mixing and ventilation by storms and turbidity currents. While the secular variations were regional or global signals caused by regional factors and global climate changes. Anoxic/euxinic benthic marine conditions prevailed throughout the middle Wuchiapingian to the early Changhsingian at Shangsi, which persisted for 3.9 Myr (256.974–253.073 Ma). This long-term Wuchiapingian anoxia event can be correlated both regionally and globally, and was caused by paleogeographic restrictions, relative high sea levels, high marine productivities, and possible global climate changes. "In addition, we found a long-term global oxygenation event occurred during the Changhsingian, which initiated at ~253.513 Ma, followed by a major oxygenation pulse at 253.073 Ma, and further intensified at 252.739 Ma at Shangsi." This Changhsingian global oxygenation event was probably triggered by an early Changhsingian global cooling event, during which the average surface ocean temperature declined ~6 ℃, and the cold climate persisted during most of the Changhsingian. This research was supported by the Chinese Academy of Sciences and the National Natural Science Foundation of China. Reference: Zheng, Q.F.*, Zhang, H., Yuan, D.X., Wang, Y., Wang, W.Q., Cao, C.Q., Shen, S.Z., 2022. High-resolution sedimentology, ichnology, and benthic marine redox conditions from Late Permian to the earliest Triassic at Shangsi, South China: Local, regional, and global signals and driving mechanisms. Earth-Science Reviews, 225: https://doi.org/10.1016/j.earscirev.2021.103898. Table 1 Summary of characteristics used to define redox conditions during deposition Conditions MBD (mm) ii Sedimentary fabric Oxygen (ml/l) Euxinic/anoxic 0 1 Well laminated; no sighs of biogenic structures. 0 (H2S) suboxic 0-5 2-4 Well to faintly discontinuously laminated; partly bioturbated. 0-0.15 Lower dysoxic 0-5 5-6 Completely bioturbated or homogenized. 0.15-0.5 Upper dysoxic/oxic 5-10 5-6 Completely bioturbated or homogenized. ≥0.5 Oxic ≥10 5-6 Completely bioturbated or homogenized. ≥2.0
Fig. 1. Lithofacies, microfacies, and storm-induced structures (A, C-E) from the top Wuchiaping Formation (A and B) and the basal Talung Formation (C-G). (Image by NIGPAS) Fig. 2. Late Permian to the earliest Triassic stratigraphic distribution of conodont zones (CZ), ichnocoenoses (Ichnoc.), sedimentological log, U–Pb ages, ichnofabirc index (ii), maximum burrow diameter (MBD), redox interval (RI), redox-condition column (RC), secular ichnofabric index (s-ii), secular maximum burrow diameter (s-MBD), secular redox-condition column (sRC), astronomical ages (AA), eccentricity cycles (E) proxied by anhysteretic remanent magnetization (ARM), and relative sea level (RSL) at the Shangsi section. The U–Pb ages are from Shen et al. (2011); the ARM data is from Wu et al. (2013). (Image by NIGPAS) Fig. 3. Driving factors for the evolution of benthic-marine redox conditions at Shangsi from the Lopingian to the earliest Triassic. (Image by NIGPAS) Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The Lantian biota, discovered from the Ediacaran basinal-facies deposition of the Lantian Formation near Lantian Town of the Anhui Province, South China, yields an assemblage representing one of the oldest known complex macrofossils. These fossils are preserved on the bedding surface of black shales in the middle part of the Lantian Formation, and their age was estimated at approximately 600 Ma. The Lantian biota, discovered from the Ediacaran basinal-facies deposition of the Lantian Formation near Lantian Town of the Anhui Province, South China, yields an assemblage representing one of the oldest known complex macrofossils. These fossils are preserved on the bedding surface of black shales in the middle part of the Lantian Formation, and their age was estimated at approximately 600 Ma. The Chuaria fossils usually with spheroidal or disk-like shapes, are the most common macrofossils in the Lantian biota. Although great majority of the Lantian Chuaria fossils are preserved as carbonaceous compressions, Chuaria has been reported to be commonly preserved as pyritization enveloped by aluminosilicate minerals in the upper Member II of the Lantian Formation. The outer minerals that envelope the pyrite layer have been assigned to quartz or aluminosilicate clay minerals. However, their exact mineral compositions as well as whether these minerals have contributed to the exceptional preservation of Ediacaran Lantian Chuaria remain unclear. Dr. WANG Wei and her research group from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS) employed light microscopy, field emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), and Raman spectroscopy techniques to revisit the preservation of pyritized Chuaria from the Lantian biota. "Our taphonomic experiments show Chuaria fossil pyritization occurs at early fossilization process and has contributed to the soft-tissue preservation." Wang says. "The pyritization process is probably divided into at least two stages, which are characterized by distinct pyrite crystal morphologies." The pyritized Chuaria fossils are enveloped by platy minerals that are a complex mixture of quartz and magnesium-rich aluminosilicates. Integrated mineral and structural pattern analyses show that these quartz and clay minerals are both secondary overgrowth on Chuaria internal mold, which probably formed as a diagenetic product concurrent with carbonate dissolution in the Lantian black shales. Their formation is probably regulated by local micro-environment near the Chuaria bodies. These enveloped minerals may facilitate preservation and identification of Chuaria fossils, but they are probably not involved in the initial fossilization process as the early diagenetic pyritization has done. This research was supported by the National Natural Science Foundation of China, the Strategic Priority Research Program of the Chinese Academy of Sciences, and the Science and Technology Research Project for the Research Institute of Petroleum Exploration and Development, CNPC. Reference: Wang Wei*, Guan Chengguo, Zhao Xianye, Fang Yan, Zhou Chuanming, Yuan Xunlai (2022) Taphonomic study of Chuaria fossils from the Ediacaran Lantian biota of South China. Precambrian Research, 369: 106529. https://doi.org/10.1016/j.precamres.2021.106529. Fig. 1 Images of the Chuaria fossils
Fig. 2 Elemental mapping and Raman spectroscopic investigations on platy minerals Fig. 3 A simplified cartoon showing Chuaria fossilization process
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Devonian witnessed the first forest on the Earth and the earliest coal formed by land plants. The Middle to Upper Devonian of West Junggar, northern Xinjiang, China yields abundant plant fossils, and finds hydrocarbon source rocks and ancient petroleum reservoirs (APR). The petroleum reservoirs in geological history were destroyed by tectonic movements to form APR. The important mark of APR is solid bitumen. Devonian witnessed the first forest on the Earth and the earliest coal formed by land plants. The Middle to Upper Devonian of West Junggar, northern Xinjiang, China yields abundant plant fossils, and finds hydrocarbon source rocks and ancient petroleum reservoirs (APR). The petroleum reservoirs in geological history were destroyed by tectonic movements to form APR. The important mark of APR is solid bitumen. Although, the age, formation and destruction of APR have been studied before, no detailed study has been conducted on the plant fossils in APR, and the stratigraphical sequence of APR in the field is different from previous studies. Therefore, it is necessary to conduct in depth study on age, stratigraphical sequence and plant fossils of APR of North Xinjiang. Recently, the Devonian Investigation Group (DIG) of Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), led by Prof. XU Honghe and Prof. WANG Yi, conducted study on age, stratigraphical sequence and plant fossils of APR of North Xinjiang. The related research results were published in Journal of Stratigraphy and the international journal Plants. Based on lithostratigraphical and palaeobotanical study to the Devonian APR, the study demonstrates that the APR belongs to the Upper Member of the Hujiersite Formation with the age of late Middle Devonian (Givetian). The core layer of APR is 2 m thick, and the lithology is dominated by sandstone and mudstone. The research also studied the genus of Barsassia in APR. Since the establishment of Barsassia in 1933, there has been a lack of systematic study for a long time, resulting in unclear and confusing generic and specific diagnoses. Here, we systematically study the Devonian lycopsid Barsassia, based on the new materials in APR. Barsassia ornata is determined as the type species of the genus, and a neotype is designated for that name. Barsassia ornata is a herbaceous lycopsid consisting of easily recognized and characteristic step-like stem and tight, pseudowhorls, and imbricate fan- or rectangular-shaped leaves, and can be used in dating and correlating the Middle Devonian terrestrial strata in Siberia, Kazakhstan and Xinjiang. References: 1. Liu, B. C; Zong, R. W; Wang, Y.; Xu, H. H*. 2021. On the age of Devonian ancient petroleum reservoir in West Junggar, northern Xinjiang, China. Journal of Stratigraphy, 45(2): 196-203. https://doi.org/10.19839/j.cnki.dcxzz.2021.0018. 2. Liu, B. C; Wang, K.; Zong, R. W; Wang, Y.; Xu, H. H*. 2021. Morphology and Nomenclature of Barsassia (Lycopsida) from the Middle Devonian of West Junggar, Xinjiang, China. Plants, 10, 2631. https://doi.org/10.3390/plants10122631.
Fig. 1：The stratigraphical sequence, outcrop and plant fossils in APR.
Fig. 2: Barsassia ornata from APR, with easily recognized and characteristic step-like stem and rectangular-shaped leaves
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
Systematic study of morphologies, textures and depositional structures in mass-transport deposits (MTDs), as well as associated sedimentary lithofacies, can also help to reveal aspects of tectonic evolution and sedimentary history of basins. Subaqueous mass-transport processes, including gravity-induced slides, slumps and debris flows, are one of the mechanisms for transport of sediment into the deep sea. They are of great significance because they shape the sea floor, record climatic and tectonic signals, represent potential catastrophic hazards for human activities and serve as hydrocarbon reservoirs. Systematic study of morphologies, textures and depositional structures in mass-transport deposits (MTDs), as well as associated sedimentary lithofacies, can also help to reveal aspects of tectonic evolution and sedimentary history of basins. However, internal structures and depositional processes of carbonate MTDs are relatively poorly understood relative to siliciclastic facies due to their comparative paucity in the rock record. Moreover, it is also challenging to decipher the evolution and internal features of MTDs using remotely-sensed data and drill cores of modern deposits. Accordingly, outcrop-scale study on carbonate MTDs is one important work of sedimentologists. During the last few years, Dr. LI Wenjie and Prof. CHEN Jitao from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS), and American cooperators worked in the Wuhai area, Inner Mongolia for several times. Multi-bedded carbonate MTDs from mid and late Darriwilian to early Sandbian are studied from the aspects of sedimentology and stratigraphy. The study is published in the international academic journal Sedimentology. Researchers measured and described the Kelimoli and Wulalike formations of several sections at centimetre scale. The MTDs layers were described in detail. Hundreds of proxies of paleoslope orientation indicators have been measured. Line drawings were made in the field and laboratory to illustrate the soft-sediment deformation structures (SSDS). According to the data and field observation, they concluded the deformational succession of carbonate slump structures, and several unique sedimentary models of carbonate mass flow. Tectonic events related to passive to foreland basin transitions, and associated platform foundering and steepening of the slope were proposed to be the trigger mechanism of the deposition of these MTDs. Their findings improved the understanding of transport mechanisms of carbonate MTDs and provided a template for predicting deformational trends of other ancient carbonate slope mass movements. Their stratigraphic and facies model may be applicable to the tectonic history of sedimentary basin analysis and unconventional hydrocarbon resource (such as shale gas) exploration of the western margin of North China. This research was supported by the Strategic Priority Research Program (B) of Chinese Academy of Sciences and National Science Foundation of U.S. Reference: Li, W. J., Chen, J. T.*, Hakim, A. J., Myrow, P. M., 2021. Middle Ordovician mass-transport deposits from western Inner Mongolia, China: Mechanisms and implications for basin evolution. Sedimentology. https://doi.org/10.1111/sed.12949.
Fig. 1 Imbricated beds and folds of the Kelimoli Formation at the Xilaifeng section Fig. 2 Breccia-filled channels of the Wulalike Formation at the Yixiantian section Fig. 3 Facies model of coarse-grained calciclastic submarine channels formed in steep siliciclastic slope settings. Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The existing researches are very limited and lack systematic studies, mainly being short material descriptions and reports. Megaspore plays an important role in the study of paleovegetation and paleocatlimatic reconstruction and stratigraphy due to its properties of preserving in situ due and clear affinity to the mother plants. However, fossil megaspores have not been fully studied due to their low productivity, which is even later started and poorer developed in China has been compared with international studies. The existing researches are very limited and lack systematic studies, mainly being short material descriptions and reports. The Tarim Basin is one of the most important petroliferous basins in China. The Mesozoic strata are important hydrocarbon source rocks of the basin. A researcher group headed by Professor LI Jianguo from Nanjing Institute of Geology and Palaeotology, Chinese Academy of Sciences (NIGPAS), has set out a work on the megaspores of the Mesozoic in the basin during the last decade. They studied several hundreds of samples collected from 34 outcrop or underground drilling well sections in the Tarim Basin. A total of 108 species of 27 genera have been identified, redescribed and illustrated. Eight palynological assemblage zones spanning the Early Triassic to Early Cretaceous are recognized based on the distribution of representative taxa and compositional changes in the megaspore assemblages. Stratigraphic and palaeoenvironmental values of selected genera and species are also discussed. This work has currently been officially published by Science Press China as "Mesozoic Megaspores and Palynomorphs from Tarim Basin, Northwest China" (Palaeontologica Sinica, Volume 202). This is the first Chinese and English language controlled research monograph on fossil macrospores in China. It will strongly promote the study of Mesozoic fossil megaspores, the stratigraphic division and correlation, and petroleum exploration in the Tarim Basin. Cover of "Mesozoic Megaspores and Palynomorphs from Tarim Basin, Northwest China" Fossil plates on the inside of this monograph
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
About 252 million years ago, more than 81 percent of animal life in the oceans and 89 percent of animal life on land went extinct. This event, called the "end-Permian mass extinction" (EPME), represents the greatest catastrophe in the history of life on Earth. The proximate driver of the event has long been a mystery. About 252 million years ago, more than 81 percent of animal life in the oceans and 89 percent of animal life on land went extinct. This event, called the "end-Permian mass extinction" (EPME), represents the greatest catastrophe in the history of life on Earth. The proximate driver of the event has long been a mystery. However, a new study led by scientists from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) and Nanjing University has now revealed that Felsic volcanism in South China drove the EPME. The study was published in Science Advances on Nov. 17. Previous studies suggested that volcano eruptions in Siberia, an event called the "Siberian Traps large igneous province (STLIP)," was the single major driver of the mass extinction event. The support for this argument comes from the observation that STLIP was large enough to perturb the global environment. The team, however, noted that temporal links between the mass extinction and volcanism were largely based on sedimentary records from South China, while the Siberian region does not contain direct evidence of biological extinction. The scientists also noted that more than one-third of the erupted volcanic rocks and the entire STLIP intrusive magmatism postdated the end-Permian mass extinction horizon. Therefore, the team wanted to determine if volcanic eruptions from other regions could help explain the EPME. In this study, the team focused on terrestrial ecosystems, which were decimated during the EPME. Typically, scientists identify ancient volcanic eruptions by looking at the abundance of volcanic rocks preserved on Earth's present-day surface, and anomalies of elemental mercury in ancient sedimentary rocks. But volcanic rocks can be weathered or covered and disappear from the Earth's surface. Furthermore, enrichment of elemental mercury in sedimentary rocks does not always indicate the presence of volcanic eruptions. To overcome this, the team pioneered a new and more efficient approach. By studying variations in elemental copper and its isotopes recorded in sedimentary rocks, the team was able to infer large-scale volcano eruptions near the studied outcrops. These sediments, collected in modern-day South China, recorded the entire EPME. The resulting extreme elemental copper enrichment and the associated anomalously light isotopic compositions in the EPME interval in South China gave the answers the researchers were looking for. They were able to show that large-scale eruptions near the South China Block were synchronous with the EPME. The new study has strengthened the case that the STLIP may not have been the sole trigger for the extinction. "This finding provides critical new insights into mechanisms that led to the extinction of animal life both in the ocean and on the land. We suggest that felsic volcanism in South China was a key contributor to the environmental deterioration that led to the end-Permian mass extinction," said Prof. ZHANG Hua from NIGPAS, the first author of the study. The discovery calls attention to the possible effects of modern climate change. The new study estimated that volcanic SO2 injections would have produced several degrees of rapid cooling before or coincident with the more protracted global warming caused by CO2 injections. Such swings in end-Permian climate from volcanic carbon and sulfur outgassing could create deadly environments for ecosystems. "One of the most interesting and worrying things about the end-Permian extinction is how similar those events are to what is happening today," said corresponding author Prof. SHEN Shuzhong from Nanjing University. "Similar to what happened during the end-Permian period, the modern Earth is facing rapid climate warming due to anthropogenic CO2 emissions."
Fig. 1 Photographs and photomicrographs of Cu-rich sulfide and charcoal from the terrestrial Permian-Triassic transition. (Image by NIGPAS)
Fig. 2 Schematic showing the formation process of copper-rich deposits within the EPME interval in South China. (Image by NIGPAS)
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The acritarch fossil assemblage in chert can be compared with other regional assemblages in the world at the same time, and can be also used for outcrop and drilling core biostratigraphic correlation, which has important industrial significance. During the Ordovician period, siliceous rocks were widely deposited in many parts of the world, including Kazakhstan and eastern Australia. Although the micropaleontology of Ordovician deep-sea cherts is relatively well documented, microfossil assemblages in Ordovician shallow-marine cherts are less well-known. Recently, associate researchers MENG Fanwei and YAN Kui, and master student YUAN Xuejun, from Nanjing Institute of Geology and paleontology, Chinese Academy of Sciences (NIGPAS), in cooperation with senior engineers ZHANG Zhili and LI Huili, from Sinopec petroleum exploration and Development Research Institute, studied the drilled carbonate rock core of Yijianfang Formation in the Middle Ordovician of Well YJ-1 in the north of Tarim Basin, China, and found a large number of chert nodules in the carbonate rock. The related research results were published in the international SCI journal Carbonates and Evaporites. Abundant fossil algal assemblages were found in the sections of chert nodules. It includes 11 genera of planktonic algae fossils (acritarch) and filamentous cyanobacteria, revealing the biological assemblage of Middle Ordovician chert facies. The Yijianfang Formation fossil assemblage indicates a deep offshore depositional environment. Sedimentological evidence also suggests that the limestone that hosts the chert interval was deposited in a low- to moderate-energy, restricted, inner carbonate platform. Cherts formed by silicification during late diagenesis. Previously, Chinese Ordovician micro planktonic algae fossils (acritarch) basically came from shale immersion. This study is the first study of Ordovician chert facies fossils in China, which enriches the understanding of Ordovician biosphere. The acritarch fossil assemblage in chert can be compared with other regional assemblages in the world at the same time, and can be also used for outcrop and drilling core biostratigraphic correlation, which has important industrial significance. This research is supported by the National Natural Science Foundation of China, the China-Israel cooperation Project of the National Natural Science Foundation of China, and the original innovation project of "from 0 to 1" of the basic frontier science research program of the Chinese Academy of Sciences. Reference: Zhang, Zl., Meng, Fw., Zheng, Qf. et al. Microfossils from nodular cherts in the Middle Ordovician Yijianfang Formation carbonates (Well YJ1X), Tarim Basin, China. Carbonates Evaporites 36, 38 (2021). https://doi.org/10.1007/s13146-021-00689-7. Figure 1. Fossil algae in nodule cherts of Yijianfang Formation in Middle Ordovician of Well YJ-1 in northern Tarim Basin, China Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The end-Permian mass extinction (EPME) led to a severe terrestrial ecosystem collapse. Insects have diversified over the past approximately 400 million years and account for roughly half of the biodiversity on Earth today. However, the ecological response of insects to the EPME remains poorly understood. The end-Permian mass extinction (EPME) led to a severe terrestrial ecosystem collapse. Insects have diversified over the past approximately 400 million years and account for roughly half of the biodiversity on Earth today. However, the ecological response of insects to the EPME remains poorly understood. Beetles (Coleoptera) are the most speciose group of extant insects, with a stratigraphic range dating back to at least the lowest Permian. They have a rich fossil record since the Permian and display a wide array of lifestyles. Their fossil record thus offers a unique and complementary perspective for studying the ecological response of insects to the EPME. Recently, postgraduate researcher ZHAO Xianye, Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS), and other researchers from China, Russia, the USA and UK analyzed the evolutionary history of early beetles. Their findings suggest that xylophagous (feeding on or in wood) beetles probably played a key and underappreciated role in the Permian carbon cycle and early archaic beetles experienced severe ecological consequences of end-Permian deforestation. These results further provide new insights into the ecological role of insects in deep-time terrestrial ecosystems as well as the ecological response of insects to deforestation and global warming. The study was published in the international academic journal eLife on Nov. 8. The research team compiled an updated database of beetles from the Early Permian to Middle Triassic based on the taxonomic revision of fossils. They analyzed the evolution of taxonomic diversity, morphological disparity and palaeoecological shifts of beetles from the Early Permian to Middle Triassic through phylogenetic and palaeoecological reconstructions and morphospace analyses of fossil material. The suite of analyses show that Permian xylophagous beetles suffered a severe extinction during the EPME largely due to the collapse of forest ecosystems, thus resulting in an Early Triassic gap of xylophagous beetles. New xylophagous beetles appeared widely in the early Middle Triassic, which is consistent with the restoration of forest ecosystems. Permian beetles probably played an important ecological role in forest ecosystems because most Permian beetles were probably xylophagous insects that consumed living and dead woody stems. Furthermore, xylophagous beetles may have been responsible for the decrease of oxygen concentrations in the Permian. The research highlights the ecological significance of insects in deep-time terrestrial ecosystems. Extant insects are suffering from dramatic declines in abundance and diversity largely due to anthropogenic deforestation and global warming. However, xylophagous insects have been largely neglected in studies of the current extinction crisis. The current study may help researchers better understand future changes in insect diversity and abundance and the consequences of such developments as the world faces global environmental change. This research was supported by the Chinese Academy of Sciences and the National Natural Science Foundation of China.
Fig. 1 Examples of Permian beetles and reconstructions. (Image by NIGPAS)
Fig. 2 Phylogeny of early beetles (A) and genus percentages of xylophagous groups (B) (Image by NIGPAS)
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
The Ediacaran Period (635–539 million years ago, Ma) is a pivotal period in Earth history, archiving the rise of complex macroscopic life. This evolutionary milestone occurred in the aftermath of extreme climate perturbations, the Cryogenian snowball Earth events, and amid dramatic changes in the global carbon cycle and ocean redox conditions. The Ediacaran Period (635–539 million years ago, Ma) is a pivotal period in Earth history, archiving the rise of complex macroscopic life. This evolutionary milestone occurred in the aftermath of extreme climate perturbations, the Cryogenian snowball Earth events, and amid dramatic changes in the global carbon cycle and ocean redox conditions. These perturbations, including the Shuram event which is the largest magnitude negative carbon isotope excursion in Earth history, have been documented worldwide, and are commonly employed to establish regional to global stratigraphic correlations. However, there is a lack of a chronostratigraphic framework at sufficient resolution for testing hypotheses related to the tempo, magnitude/duration of the events (especially the Shuram), their global expression, or their co-relationship with biospheric evolutionary innovations. Published in Science Advances, a study by an international research team led by Prof. Zhu Maoyan (Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences) presents new radio-isotopic dates from Ediacaran successions in South China and White Sea area. The new dates provide age constraints on both the Ediacaran fossil assemblages and the carbonate carbon isotope perturbations. The upper Ediacaran is characterized by the typical Ediacara-type fossils. Three assemblages of the fossils have been recognized: the Avalon, White Sea, and Nama. The age ranges of the Avalon and Nama assemblages have been constrained at 575–560 Ma and 550–539 Ma, respectively. New dates from the study indicate that the White Sea assemblage spans a time interval started earlier than 557 Ma and ended later than 553 Ma. The age constraints on these three fossil assemblages can facilitate our understanding of the evolution in the late Ediacaran. New dates from South China also provide age constraints on the Doushantuo acanthomorphic acritarchs, Weng’an biota, Wenghui biota, Miaohe biota, and Ediacara-type fossils in the Dengying Formation. The terminal timing of the Shuram event was constrained at 551 Ma. However, the lack of high precision radio-isotopic dates and the complexity of local stratigraphy have given rise to much debate about the number of negative carbon isotope excursions in the late Ediacaran and the age of the Shuram event. The new dates indicate that there are two negative carbon isotope excursions in 575-550 Ma. The older and long-lasting one is the Shuram event, and the younger and short-lived one occurred at 550 Ma. The authors also compile a global Ediacaran geochronology database and suggest that the Shuran event occurred between 575 Ma and 565 Ma with an uncertainty on the order of a few million years. Older than the Shuram event, another short-lived negative carbon isotope excursion, which is locally called WANCE in South China, is dated at ~587 Ma. The presented Ediacaran age model for the carbon cycle perturbations and fossil records provides the necessary chronometric context to test causal relationships, if any, between them. At the current resolution, these transitions in the fossil record coincide with the carbonate carbon isotope excursions, suggestive of a potential causal relationship between environmental perturbations recorded in the carbon cycle and biological turnovers. The study was supported by grants from the Chinese Academy of Sciences, the National Natural Science Foundation of China, the Natural Environment Research Council of the UK, the United States National Science Foundation, and the Russian Science Foundation. Reference: Yang, C.*, Rooney, A.D.*, Condon, D.J., Li, X.-H., Grazhdankin, D. V, Bowyer, F.T., Hu, C., Macdonald, F.A., and Zhu, M.*, 2021, The tempo of Ediacaran evolution. Science Advances, 7, eabi9643. https://www.science.org/doi/10.1126/sciadv.abi9643. Fig. 1 Integrated radio-isotopic dates, fossil ranges, and carbon isotopic profile of the Ediacaran Period
Contact: LIU Yun, Propagandist Email: yunliu@nigpas.ac.cn Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences Nanjing, Jiangsu 210008, China
