Devonian witnesses great increases of the land plant diversity and the plant type. All kinds of plants except angiosperms have fossil records in the Devonian. The main euphyllophyte lineages (i.e. ferns sensu lato, progymnosperms and gymnosperms) had evolved laminate leaves by the Late Devonian. The evolution of laminate leaves, however, remains unclear for early-diverging ferns, largely represented by fern-like plants. Recently, a cooperative study was carried out by Prof. XU Honghe from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (CAS) and researchers from Peking University and Institute of Botany, CAS. The study presents a new fern-like taxon with pinnules, which provides new insights into the early evolution of laminate leaves in early-diverging ferns. In the study, a new fern-like taxon, Shougangia bella is described from the Upper Devonian (Famennian) Wutong Formation of Anhui and Jiangsu Provinces, South China and represents an early-diverging fern with highly derived features. Shougangia has a partially creeping stem with adventitious roots only on one side, upright primary and secondary branches arranged in helices, tertiary branches borne alternately or (sub)oppositely, laminate and usually lobed leaves with divergent veins, and complex fertile organs terminating tertiary branches and possessing multiple divisions and numerous terminal sporangia. Shougangia provides unequivocal fossil evidence for laminate leaves in early-diverging ferns. It suggests that fern-like plants, along with other euphyllophyte lineages, had independently evolved megaphylls by the Late Devonian, possibly in response to a significant decline in atmospheric CO2 concentration. Among fern-like plants, planate ultimate appendages are homologous with laminate pinnules, and in the evolution of megaphylls, fertile organs tend to become complex. The study was published as a cover paper in the recent issue of Annals of Botany. Related information of this paper: Wang D-M*, Xu H-H*, Xue J-Z, Wang Q, Liu L, 2015. Leaf evolution in early-diverging ferns: insights from a new fern-like plant from the Late Devonian of China. Annals of Botany, 115: 1133-1148. doi:10.1093/aob/mcv049 Part and counterpart specimens of the vegetative Shougangia The preparation processes and the reconstruction (right) of the fertile portion of Shougangia
Flat-pebble conglomerates (limestone breccias and conglomerates) (Fig. 1) are a common phenomenon in the Cambrian successions worldwide. They bear important geological implications that have attracted geologists for several decades. There are, however, still controversies on their origins, especially those of the breccias with abundant vertically orientated clasts. The Furongian (upper Cambrian) Chaomidian Formation of the North China Platform contains numerous levels of limestone breccias and conglomerates that provide an excellent example to look into their formative processes. These breccias and conglomerates have been the focus of study and discussion since the 1980s, but yet there is still no consensus with respect to their geneses. Recently, Van Loon and others argued that the vertically orientated clasts of the breccias developed by a number of simultaneous “fountains” on the paleo-seafloor; the “fountains” formed by upward-directed fluidized flows originated from the sediment underlying the brecciated limestones. In order to understand the formative processes of flat-pebble conglomerate, Dr. CHEN Jitao from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences briefly overviewed and specifically discussed the hypothesis proposed by Van Loon et al. (2013). While the novel “fountain” hypothesis is not impossible, based on field evidences and theoretical considerations, however, it is most likely that the vertically orientated clasts resulted from their re-orientation by upward flow of thixotropically liquidized, uncemented argillaceous sediment that was interbedded with brecciated limestone fragments. Besides, the deformation processes most likely took place under shallow burial. Further investigations by experimental analysis and model simulation may help to delineate and clarify the formative processes of these unusual Cambrian breccias. In addition, CHEN Jitao was invited by Prof. Paul Myrow from Colorado College as a co-corresponding author, to carry out the researches on some unusual soft-sediment deformation structures found in Rocky Mountain, western Colorado, including slide scarps, thrusted beds, irregular blocks and internally deformed beds (Figs 2 and 3). These features represent parts of beds that detached, moved up onto and some distances across, the laterally adjacent undisturbed bed surfaces. Deformation of thin intervals of mud on the ocean floor by moving blocks rules out the possibility of storm-induced deformation, as the mud was not eroded by high shear stresses that would accompany the extremely large forces required to produce and move the blocks. Finally, internally deformed beds are characterized by large blocks, fitted fabrics of highly irregular fragments, and contorted lamination, which represent heterogeneous deformation, such as brecciation and liquefaction. The deformation structures were produced by earthquakes linked to the reactivation of Mesoproterozoic, crustal-scale shear zones in the central Rockies during the Late Cambrian. Analysis of the deformation structures indicates very large body forces, and calculated earthquake-generated ground motion velocities of ~1.6 m/s. These correspond to moment magnitudes of ~7.0 or more and a Mercalli Intensity of X+. These are the only known magnitude estimates of Phanerozoic (other than Quaternary) large-intensity earthquakes for the Rocky Mountain region, and they are as large as, or larger than, previous estimates of Proterozoic earthquakes along these major shear zones of the central Rockies. These studies were financially supported by the National Natural Science Foundation of China, and were recently published by Science China Earth Sciences and sedimentology. Related information of these papers: 1. Chen, J., 2015. Origin of the Furongian limestone breccias in the North China Platform. Science China Earth Sciences 58, 770–775. 2. Myrow, P.M.*, Chen, J.*, 2015. Estimates of large magnitude Late Cambrian earthquakes from seismogenic soft-sediment deformation structures: Central Rocky Mountains. Sedimentology 62, 621–644. Fig. 1. Various limestone breccias and conglomerates in the Furongian Chaomidian Formation of the North China Platform. (a)-(b) Limestone conglomerate with imbricated clasts, indicating they were reworked by currents. (c)-(d) Limestone breccia containing undulatory platy clasts and abundant vertically orientated clasts that were most likely formed by soft-sediment deformation of limestone-marlstone alternations. Fig. 2. Irregular blocks and relationships to underlying and overlying layers. (A) Two stacked blocks representing possible duplex structure. (B) An irregular block showing deep penetration into the underlying bed. (C) An irregular block with deformation of laterally adjacent grainstone and shale. (D) Close-up showing that some grainstone and shale beds were forced downward, and others forced upward (white arrows) during lateral movement of the block (yellow arrow). Fig. 3. Thrusted bed and irregular blocks. (A) Line drawing showing heterogeneous deformation of laterally adjacent sediment around an irregular block (center). (B) Large irregular block on a thick bed, which slid across the upper surface and inserted into the overlying strata. Hammer is about 30 cm long. (C) Irregular block with flat base and irregular top, showing heterogeneous deformation of laterally adjacent sediment. (D) Close-up showing brittle failure of thin grainstone beds and ptygmatically folded grainstone dikes in shale above pencil cap. Fig. 4. Schematic model for the formation of various deformation features in the Dotsero and Manitou formations. (A)–(E) Deformation at the sediment-water interface. (F)–(J) Deformation taking place under a thin layer of much-rich strata.
A paper entitled “Triassic-Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations Junggar Basin, ürümqi, China” by Prof. SHA Jingeng from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and his colleagues has been recently published online in PNAS. Our understanding of Triassic and Early Jurassic high-latitude climate, biotic evolution, mass extinction, and geochronology is very poor in contrast to that of the contemporaneous tropics. This poor resolution impairs an elucidation of the basic patterns of Earth system function during the early Mesozoic. Besides, integral to the long-term chaotic behavior of the Solar System are the secular resonances of the planets, particularly for the inner Solar System. Analysis of the LITH proxy of environmental change shows that an astronomical signal in which obliquity is dominant can be extracted from lacustrine strata of the high-latitude (~60o N) Junggar Basin straddling the end-Triassic extinction and Triassic-Jurassic boundary. This is dramatically different from the climate precession-dominated continental tropics. In combination, the data are incompatible with published astronomical solutions for the Triassic-Jurassic in phase and amplitude, consistent with chaotic behavior of the Solar System whereas, at the same time, the Earth-Mars orbital resonance seems to have been in today’s two-to-one ratio of eccentricity to inclination, providing a constraint for the Earth-Mars orbital resonance for around 201 Ma. With the prospect of the acquisition of better temporally resolved records from deeper lake settings in the Junggar and other basins, the use of more directly climate-sensitive proxies, and additional exploration of the paleobiological context of the strata, it will be possible to test these findings, constraining the history of Solar System chaos, during this transitional time in Earth history. The research was financially supported by the National Basic Research Program of China, National Natural Science Foundation of China, Chinese Academy of Sciences, etc. Related information of this paper: Jingeng Sha, Paul E. Olsen, Yanhong Pan, Daoyi Xu, Yaqiong Wang, Xiaolin Zhang, Xiaogang Yao, and Vivi Vajda. Triassic-Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations (Junggar Basin, ürümqi, China). PNAS. Doi:10.1073/pnas.1501137112. Paleogeographic position of the Junggar Basin (A), present position of the Junggar Basin (B), and map of the surficial geology of the ürümqi area (C). LITH Index data of Junggar Basin (C) and other correlative sections. Photograph of portion of the Haojiagou section including beds 45-53.
The Early Carboniferous was an important interval in geological history characterized by the transition from the greenhouse climate of the Devonian to the icehouse climate of the Carboniferous-Permain. The first glaciation of the Carboniferous-Permain Ice Age is thought to have occurred during the mid-Tournaisian based on glacial deposits, eustatic regression, and positive excursions in carbon (δ13Ccarb and δ13Corg), oxygen (δ18O), nitrogen (δ15N) and strontium (δ87Sr) isotopes. To date, it is still unclear about the process of carbon-nitrogen cycles and their relationships to contemporaneous changes in marine environments during the mid-Tournaisian. To better understand the process of carbon-nitrogen cycles and paleoenvironmental changes during this critical interval, a high-resolution study of the δ13Ccarb and δ15N records of the Tournaisian at two sections (Malanbian and Long'an) was undertaken by Dr. YAO Le and his colleagues from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, China University of Geosciences, Wuhan, and so on. Their C-isotope profiles document a large positive excursion, herein termed the ‘mid-Tournaisian carbon isotope excursion’ (TICE), during the Siphonodella isosticha conodont Zone. The TICE event coincided with sedimentologic and oxygen-isotopic evidence of climatic cooling and glaciation during the mid-Tournaisian. It was probably triggered by an increase in organic carbon burial rates linked to changes in global-ocean circulation. The study sections also document a large positive shift in δ15N which is coincided with TICE and thus may have been linked to ocean-circulation changes that resulted in intensified upwelling and an increase in water-column denitrification. The continuation of the N-isotope shift over millions of years may have been linked to glacio-eustatic fall and a long-term shift in the locus of denitrification from continental-shelf sediments to continent-margin oxygen-minimum zones. The TICE event thus marks the onset of sustained continental glaciation during the Late Paleozoic Ice Age. The paper was published in Chemical Geology, and the research was financially supported by the National Natural Science Foundation of China and the Ministry of Science and Technology Foundation Project. Reference: Yao, L., Qie W.K., Luo, G.M., Liu, J.S., Algeo, T.G., Bai, X., Yang, B., Wang, X.D., 2015. The TICE event: Perturbation of carbon-nitrogen cycles during the mid-Tournaisian (Early Carboniferous) greenhouse-icehouse transition. Chemical Geology, 401: 1-14.
Lithologic column, conodont biozones, δ15N, δ13Ccarb, Corg/N and carbonate content at the Malanbian (a) and Long'an (b) sections Model for ocean-circulation control of δ15N variation during greenhouse climate scenario (a) and icehouse climate scenario (b) in the Tournaisian
Many animals care for and protect their offspring to increase their survival and fitness. Insects care for their young using a range of strategies: some dig underground chambers for their young, whilst others carry their brood around on their own bodies. However, it was unclear when these strategies first evolved in insects. Professor ZHANG Haichun from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and his team, reported the earliest fossil evidence of an insect caring for its young, in the form of a female insect preserved with her brood in a specimen of ancient amber. The amber comes from northern Myanmar, where amber deposits are around 95–105 million years old. The fossilised insect is an adult female scale insect with a cluster of around 60 eggs on her abdomen. Six young scale insect nymphs are also preserved in the same piece of amber. They named this newly discovered species Wathondara kotejai, after an earth goddess in South-East Asian Buddhist mythology and the late Polish entomologist Jan Koteja. Most scale insect fossils found to date have been males. Fossilised adult females are scarcer, most likely because female scale insects are wingless and less mobile and therefore less prone to accidental burial. The fossil is therefore a rare find, and it is also sufficiently well preserved to reveal that the female’s eggs are contained within a wax-coated egg sac. Today there are many species of scale insects, most of which are parasites of plants and many are economically important pests of trees and shrubs. In living relatives of W. kotejai, females use a similar wax coating to protect themselves and their offspring: young nymphs hatch inside the egg sac and remain there for a few days before emerging into the outside world. This new fossil provides a unique insight into the anatomy and life cycle of a long-extinct insect; it also demonstrates that brood care in insects is an ancient trait that dates back to at least around 100 million years ago at the height of the age of the dinosaurs. This research was supported by Chinese Academy of Sciences, National Basic Research Program of China, and State Key Laboratory of Palaeobiology and Stratigraphy (NIGPAS), and Alexander von Humboldt-Foundation. The paper was published in eLife (Wang Bo, Xia Fangyuan, Wappler T., Simon E., Zhang Haichun, Jarzembowski E.A., Szwedo J. (2015) Brood care in a 100-million-year-old scale insect. eLife, 4: e05447). The fossilied insect and the six young scale insect
Hitherto there is no record of typical flower in the pre-Cretaceous all over the world. Previously, the earliest typical flower is Callianthus dilae from the 125 million-year-old Early Cretaceous Yixian Formation. Recently, Professor LIU Zhongjian from National Orchid Conservation Center of China and Professor WANG Xin from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences reported their discovery of a typical flower, Euanthus panii, from the 162 million-year-old Jurassic stratum in western Liaoning, China in online published Historical Biology. Euanthus panii has all the flowers parts required for a typical flower, including calyx, corolla, androecium, and gynoecium. Its sepals and petals are well-differentiated, its anthers are tetrasporangiate, and its gynoecium includes a style and an unilocular half-inferior ovary. Several unitegmic ovules are enclosed inside the ovary. These characters make Euanthus panii the currently earliest Jurassic typical flower. The discovery of Euanthus panii opens a door for the research on origin of angiosperms. Liu Z.-J., Wang X*. A perfect flower from the Jurassic of China. Historical Biology, http://dx.doi.org/10.1080/08912963.2015.1020423
Left, the holotype of Euanthus panii; Right, the reconstruction of Euanthus panii.
A scanning electronic microscope image of the 600 million-year-old sponge-like animal fossil On March 9, 2015, Prof. ZHU Maoyan, Dr. YIN Zongjun and Dr. ZHAO Fangchen from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and their international colleagues described a 600 million-year-old body fossil with sponge-like characteristics that predates the Cambrian period by 60 million years. This study has been published online in Proceedings of the National Academy of Sciences as PNAS plus. Phylogenetic studies have suggested that sponges and eumetazoan animals may have shared a common ancestor more than 200 million years before the onset of the Cambrian period 541 million years ago, although unequivocal fossil evidence of such an ancestor is scant. ZHU Maoyan and colleagues analyzed a well-preserved 600 million-year-old fossil displaying multiple characteristics of modern sponges. Flat tile-like features on the external surface, punctuated with small pores, resemble pinacocytes on modern sponges. The authors report that the inner surface is covered with a regular pattern of uniform pits, with many pits surrounded by collars, similar to sponge choanocytes. Discovery of additional specimen would confirm that the fossil represents a Precambrian sponge, yet features of the fossil are consistent with sponge anatomy, including a basal anchor similar to a sponge holdfast and orifices for water inflow and outflow. The results suggest that advanced forms of sponges were likely extant 60 million years before the Cambrian period, and that fossils of similarly advanced eumetazoans may yet lie in the fossil record. This research was supported by National Basic Research Program of China, Chinese Academy of Sciences, the National Natural Science Foundation of China and State Key Laboratory of Palaeobiology and Stratigraphy (NIGPAS). Related information of this paper:Yin ZJ, Zhu MY, Davidson EH, Bottjer DJ, Zhao FC, Tafforeau P. Sponge grade body fossil with cellular resolution dating 60 Myr before the Cambrian. PNAS. Overall anatomy of the specimen (a, b) and flattened surface cells and base or holdfast (c, d, e, f, g, h).
Rhyniophytoids are thought to be one of the most original vascular plant groups which were firstly found from the Rhynie chert Lagerst?tte, Aberdeenshire, Scotland and from then, this group was rarely found elsewhere. Recently, study by Prof. XU Honghe from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences and his colleagues discovered the fertile structure showing rhyniophytoid’s affinities through re-examinations to specimens assigned to zosterophylls from the Lower Devonian of Guangxi, southwestern China. Newly-discovered plant is small-sized, dichotomous branched, with terminal single sporangium, showing similar to the genus Aberlemnia Gonezet Gerrienne and being also comparable to some mesofossil morphotypes of early land plants from the Early Devonian (Lochkovian) Old Red Sandstone floras. This study adds new data to the generally zosterophyll-dominated Early Devonian floras of South China and sheds some lights on the palaeophytogeography of rhyniophytoids. This work is supported by the National Natural Science Foundation of China and State Key Laboratory of Palaeobiology and Stratigraphy (NIGPAS). It is published as: Xu H-H, Xue J-Z, Wang Q. 2015. Notes on a fertile rhyniophytoid from the Lower Devonian of Guangxi, southwestern China. Historical Biology: An International Journal of Paleobiology. 27, 294-298.
Rhyniophytoid from the Lower Devonian of Guangxi, South China
The robust spines and sclerites of the early to middle Cambrian ‘mollusc’ Wiwaxia are ubiquitous in suitably preserved deposits, but are strikingly absent from the Chengjiang Lagerst？tte (Cambrian Stage 3, Yunnan Province, SW China). Recently, Dr. ZHAO Fangchen and colleagues from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, with Dr. Smith Martin from Cambridge University, report the first record of Wiwaxia sclerites from the Chengjiang deposit, published in Geological Magazine, extending the record of the genus to the earliest Cambrian Series 2. This reinforces the cosmopolitan distribution of this iconic Cambrian lophotrochozoan and demonstrates the strong faunal continuity that unites distant Cambrian Lagerst？tten. This research was supported by Chinese Academy of Sciences, National Basic Research Program of China and the National Natural Science Foundation of China. Related information of this paper: Zhao, F.*, Smith, M. R., Yin, Z., Zeng, H., Hu, S., Li, G., Zhu, M., 2015. First report of Wiwaxia from the Cambrian Chengjiang Lagerst？tte. Geological Magazine, 152 (2): 378–382. Sclerites of Wiwaxia. (a–d) from the lower Cambrian Chengjiang biota, and (e) from the middle Cambrian Burgess Shale biota Distribution of Wiwaxia. (a) Stratigraphic distribution. (b) Palaeogeographic distribution
The Devonian-Carboniferous transition was a period of major biotic and paleoenvironmental change characterized by one of the biggest Phanerozoic mass extinction events, the Hangenberg mass extinction. This event eliminated all the Paleozoic stromatoporoids from the ocean, leading to the demise of metazoan reef and changes of marine community. It was also accompanied by a distinct perturbation to the global carbon cycle recorded by positive excursions in δ13Ccarb and δ13Corg. To better understand paleoenvironmental changes and controls on δ13Ccarb variation during this critical interval, an integrated study of the litho-, bio-, and chemostratigraphy of the Devonian-Carboniferous boundary at four sections (Qilinzhai, Malanbian, Gedongguan and Long’an) in South China was undertaken by Dr. QIE Wenkun and his colleagues from Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences. Sedimentological data record a major regression in the Middle Siphonodella praesulcata Zone, which coincided with the Hangenberg Extinction (HE) in South China. Their new δ13Ccarb data document a negative δ13Ccarb shift near the base of the Middle Si. praesulcata zone, which may have been related to the HE. Prior to and during the HE, respiration of organic matter contributed abundant 12C-enriched dissolved inorganic carbon (DIC) to the restricted Nanning carbonate platform, resulting in a negative vertical δ13CDIC gradient in the study area. In the Upper Si.praesulcata Zone, all four sections exhibit a positive δ13Ccarb shift, suggesting that a vigorous biological pump existed in the aftermath of the latest Devonian glaciation. However, peak δ13Ccarb values differ markedly among the study sections, suggesting that local carbon cycling processes (e.g. input of terrestrial organic matters and nutrients, remineralization of organic matters) played an important role during the initial post-glacial transgression.
The paper was published in Palaeogeography, Palaeoclimatology, Palaeoecology, and financially supported by the National Natural Science Foundation of China.
Reference: Qie, W.K., Liu, J.S., Chen, J.T., Wang, X.D., Mii, H.S., Zhang, X.H., Huang, X., Yao, L., Algeo, T.J., Luo, G.M., 2015, Local overprints on the global carbonate δ13C signal in Devonian-Carboniferous boundary successions of South China. Palaeogeography, Palaeoclimatology, Palaeoecology 418, 290-303. (a) Early Tournaisian global paleogeographic reconstruction (base map courtesy of Ron Blakey, http://jan.ucc.nau.edu/~rcb7/). (b) Early Tournaisian paleogeographic map of South China craton showing study section localities. (c) Generalized stratigraphy of the Devonian–Carboniferous succession in South China Correlation of the δ13Ccarb profiles of the four study sections in South China
