Taphonomy and paleoecology(biological behavior)of the Early Cretaceous fish fossils are poorly described.This study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Meso...Taphonomy and paleoecology(biological behavior)of the Early Cretaceous fish fossils are poorly described.This study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Mesozoic strata of western Liaoning Province,NE China.The XRD analysis shows that gismondine is the dominant clay minerals that could have contributed to the preservation of Lycoptera fossils and microbial mat fragments in the fossil-bearing horizon.Gismondine may have formed under volcanism-related hydrothermal regime that was transformed from crystal and lithic fragments.Theμ-XRF imaging analysis shows a dominant chemical composition of Al,Si,P,S,Rh,K,Ca,Ti,C,Cr,Mn,Fe,Ni,among which P,Ca,C and S are enriched in the fish skeleton in comparison to the matrix.This suggests a dominant apatite composition for the fish skeleton.Hydrothermal influence did not smear off these organic signals probably because of protection of gismondine.The coexistance of C and S with Ni is assumed to represent recovered primary productivity following volcanic explosions and toxic gas emissions.The head of juvenile fish stays close to the body of adult fish.Pending further discoveries,such phenomenon is interpreted to suggest that adult fish actively protected juvenile fish in the presence of environmental pressures such as anoxia and deterioration of water quality induced by volcanism.Ocean acidification and hypoxia in association with volcanism created a harmful environment causing mass extinction of fish.The adult Lycoptera protected their juveniles by its body at the moment before death.Such biological behavior will be increasingly reported given the wide occurrence of Lycoptera in Mesozoic strata.展开更多
Through taphonomical analyses of Crassostrea shell beds included in several Japanese Cretaceous strata, paleoecological and sedimentological significance of intertidal muddy and sandy bottom dwelling oysters are exami...Through taphonomical analyses of Crassostrea shell beds included in several Japanese Cretaceous strata, paleoecological and sedimentological significance of intertidal muddy and sandy bottom dwelling oysters are examined. The Upper Cretaceous Crassostrea shell beds show a variety of modes of occurrence, lithological changes and sedimentary structure, suggesting composite formative, paleoecological and sedimentary processes. Crassostrea seems to have adapted from muddy substratum during early Cretaceous to coarser sandier substratum often influenced by physical turbulence such as tidal currents and waves during the mid-Cretaceous time, associated with increasing in shell size and thickness, and colony dimension.展开更多
Jehol Biota in western Liaoning and northern Hebei has been a hot topic of global concern,a large number of exquisite fossils were found in Yixian group Sihetun,such as Sinosauropteryx,Protarchaeopteryx, Caudipteryx a...Jehol Biota in western Liaoning and northern Hebei has been a hot topic of global concern,a large number of exquisite fossils were found in Yixian group Sihetun,such as Sinosauropteryx,Protarchaeopteryx, Caudipteryx and Confuciusornis.Scientists consider the discovering of Sinosauropteryx discovered so far as the earliest ancestor of birds.According to the dates of root layer,we can see warm and humid,lakes展开更多
Forensic taphonomy as a discipline requires standardization to satisfy Daubert criteria for sci-entific data to be admissible in court.In response,there has been a shift towards quantifica-tion of methodology and esti...Forensic taphonomy as a discipline requires standardization to satisfy Daubert criteria for sci-entific data to be admissible in court.In response,there has been a shift towards quantifica-tion of methodology and estimating the postmortem interval.Despite these advances,there are still biases and limitations within the discipline not explicitly addressed in the early stages of experimental design nor in final published works.In this article,unresolved debates with respect to the conductance and reporting of forensic taphonomic research are reviewed,beginning with the nature of experimental cadavers,human or animal analogues and their body size,and second,the forensic realism of experimental setups,specifically with respect to caging,clothing and number of carcases.Pigs,albeit imperfect,are a good model to gain a general idea of the trends that may be seen in humans in subsequent validation studies in facilities where human donors are available.To date,there is no consen-sus among taphonomists on the extent of the effect that body mass has on decomposition progression.More research is required with both human cadavers and non-human analogues that builds on our current knowledge of forensic taphonomy to answer these nagging questions.This will enable the discipline to make the reliable assumption that pigs and donor decomposition data can be applied to homicide cases.A suite of experimental design aspects is suggested to ensure systematic and standardized data collection across differ-ent biogeoclimatic circumstances to identify and quantify the effects of potential confounding variables.Such studies in multiple,varied biogeographic circumstances with standardized protocols,equipment and carrion will facilitate independent global validation of patterns.These factors are reviewed to show the need for adjustments in experimental design to ensure relevance and applicability of data within locally realistic forensic situations.The initiation of a global decomposition data network for forensic taphonomists is recommended.展开更多
Abstract The taphonomy of fishes living in lacustrine environments has been extensively studied in both the laboratory and the fossil record;the taphonomy of marine fishes,however,is poorly known.Triassic marine fishe...Abstract The taphonomy of fishes living in lacustrine environments has been extensively studied in both the laboratory and the fossil record;the taphonomy of marine fishes,however,is poorly known.Triassic marine fishes with heavy ganoid and cosmoid scales,which provided protection from rapid taphonomic loss,offer a means to examine marine fish taphonomy in the fossil record.Four genera of Early Triassic fishes(the ray-finned actinopterygians Albertonia,Bobasatrania,Boreosomus,and the lobe-finned coelacanth(sarcopterygian),Whiteia)from the Wapiti Lake,British Columbia locality of the Lower Triassic Sulphur Mountain Formation were examined in order to gain a better understanding of the taphonomy of fish in marine environments,determine ambient environmental conditions in the region during the Early Triassic,and ascertain the habitat and mode of life of the fish.Results indicate that environmental conditions that contributed to the preservation of the fossil fishes of the current study included deposition in deep,quiet waters,which reduced the odds of disarticulation,colder waters under higher pressure,which slowed decay and limited postmortem floatation,and waters that were anoxic,which discouraged predators and scavengers.In addition,the thickness of the primitive ganoid and cosmoid scales of the fossil fishes also increased their preservation potential.Taphonomic,physiological and environmental indicators suggest that Whiteia,Albertonia,and possibly Bobasatrania lived in deep,cold waters near the oxygen minimum zone,while Boreosomus lived higher in the water column.While the anatomical and physiological characteristics of modern fishes will likely continue to inhibit marine taphonomy studies,examination of ancient fish,particularly those with ganoid or cosmoid scales,may provide future avenues of research to gain a better understanding of marine fish taphonomy and provide a powerful tool to examine ancient fish behavior and their environment.展开更多
The exquisitely preserved fossil embryos of Markuelia recovered from the limestones of the Middle Cambrian Haoqiao Formation and Upper Cambrian Bitiao formation in western Hunan, South China are described and illustra...The exquisitely preserved fossil embryos of Markuelia recovered from the limestones of the Middle Cambrian Haoqiao Formation and Upper Cambrian Bitiao formation in western Hunan, South China are described and illustrated in detail for the first time. A new species Markuelia elegans sp. nov. is established based mainly on embryos from the Upper Cambrian. A few of animal's resting eggs, which are comparable with those of the Ediacaran Doushantuo Formation, have been also found in the Upper Cambrian of western Hunan. The membrane of one egg from the uppermost Cambrian has been replaced by pyrite and the overgrowth of the pyrite crystals exhibits a unique inorganic pattern termed herein 'Pseudoembryo'. The taphonomic setting in deeper water with possible strong reducing conditions promoted the excellent preservation for the Markuelia specimens. The study of Markuelia provides not only constraint on the anatomy, affinity, embryonic development and phylogenetic significance of this wormlike animal and but also opens a new window onto the evolution and development of the earliest animals.展开更多
El Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain (Cantabria), has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. R...El Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain (Cantabria), has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. Relevant data provided herein for biogeochemistry of the amber, palynology, taphonomy and arthropod bioinclusions complement those previously published. This set of data suggests at least two botanical sources for the amber of El Soplao deposit. The first (type A amber) strongly supports a source related to Cheirolepidiaceae, and the second (type B amber) shows non-specific conifer biomarkers. Comparison of molecular composition of type A amber with Frenelopsis leaves (Cheirolepidiaceae) strongly suggests a biochemical affinity and a common botanical origin. A preliminary palynological study indicates a regional high taxonomical diversity, mainly of pteridophyte spores and gymnosperm pollen grains. According to the preliminary palynological data, the region was inhabited by conifer forests adapted to a dry season under a subtropical climate. The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter, and subsequent great accumulation of amber plus plant cuticles. In addition, for the first time in the fossil record, charcoalified plant fibers as bioinclnsions in amber are reported. Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber. Lastly, new findings of insect bioiuclusions, some of them uncommon in the fossil record or showing remarkable adaptations, are reported. In conclusion, a documented scenario for the origin of the El Soplao amber outcrop is provided.展开更多
Fossil ferns are abundant and diverse in the Permian Cathaysian Flora of Shanxi, North China. Although plants assemblages of the Carboniferous and Permian have been extensively investigated, their palaeoecology and es...Fossil ferns are abundant and diverse in the Permian Cathaysian Flora of Shanxi, North China. Although plants assemblages of the Carboniferous and Permian have been extensively investigated, their palaeoecology and especially the paleoecology of ferns has not been studied in detail. Recent reinvestigation of Oligocarpia gothanii has revealed its growth habit and cloning reproduction strategy, but most previous studies lack integrated sedimentological and taphonomic data. In this study, new materials of O. gothanii have been collected from a floodplain setting in the middle Permian Lower Shihhotse Formation of southeastern Shanxi. These plant fossils were found in a lenticular claystone associated with rooting structures. They are characterized by aphlebia at the base of the penultimate rachis. Sedimentological, taphonomic and morphological analyses were conducted to understand the growth habit and ecology of the fern. The result indicates that the Oligocarpia gothanii had a prostrate, ground cover growth habit, and was dominant in pioneer floras that colonized disturbed floodplains.展开更多
Taphonomy refers primarily to the study of processes between death and final burial of an organism or a group of organisms, including both taphonomic loss and taphonomic gain. Taphofacies refers to the taphonomic tra...Taphonomy refers primarily to the study of processes between death and final burial of an organism or a group of organisms, including both taphonomic loss and taphonomic gain. Taphofacies refers to the taphonomic traits, which include the taphonomic attributes of all fossils and the lithologic features of their enclosing rocks. Taphofacies is different from lithofacies; as a taphonomic environmental setting or taphonomic condition, it is more useful than the stratigraphic body of rock. Based on the features of fossil preservation integrated with stratigraphic, sedimentologic and paleontologic evidence from Devonian of Longmenshan area, it is distinguished and described 11 taphofacies models. For convenience in the field, the name of each taphofacies is divided into taphonomic and lithologic traits. The spatial relations between each taphofacies and the taphofacies with the benthic assemblages 1-6 are discussed.展开更多
Silica-phosphatic nodules are abundant in black shales of the Yanjiahe Formation in the Three Gorges Area of South China,which is correlated to the Fortunian Stage,Terreneuvian Series,Cambrian System.The nodules are r...Silica-phosphatic nodules are abundant in black shales of the Yanjiahe Formation in the Three Gorges Area of South China,which is correlated to the Fortunian Stage,Terreneuvian Series,Cambrian System.The nodules are rich in small shelly fossils and hence attract the attention of numerous paleontologists and sedimentary geologists.However,the genesis of the nodules and the preservation of the small shelly fossils are poorly understood.Here we analyze morphological,structural,mineralogical and chemical features of the nodules in multiscale using a combination of micro-X-ray fluorescence spectroscopy,X-ray diffraction,scanning electron microscopy and confocal laser Raman spectroscopy.Results reveal that nodules are concentric in chemical and mineralogical compositions,comprising a silica-phosphatic core encrusted sequentially by a phosphatic zone,a siliceous zone and a very thin pyrite outer rim.The black shales hosting the nodules demonstrate a laminated texture of alternating clayey and silty laminae,which were respectively deposited in sulfidic/less sulfidic,high/low production,intense/weak chemical weathering conditions.The phosphogenesis of the nodules resulted in the phosphatization of small shelly fossils,which prevented the fossils from being dissolved during diagenesis,whereas the silica encrustation sealed the fossils within the nodules and thus protected the fossils from alteration by deep burial and surface weathering.展开更多
Representativity of biota in the biosphere also have similar significance in the lithosphere after their death. Recently, taphonomic representation of biota in the lithosphere has been widely used for minimizing the b...Representativity of biota in the biosphere also have similar significance in the lithosphere after their death. Recently, taphonomic representation of biota in the lithosphere has been widely used for minimizing the biases in palaeo-environmental reconstructions including global climate change. In September 2001, a sediment trap was installed at the central area of the Loch Coire Fionnaraich (LCFR), a small, oligotrophic mountain loch in northwest Scotland for a taphonomic study of cladoceran zooplankton. The trap was emptied on a seasonal basis, where an average 0.14 g dry material was recovered in each season, January, May and August 2002 respectively. A sediment core was also taken from near the sediment trap location. The top 0.5 cm section, the 'core' was used for a comparative study with the trap sediment samples. The planktonic Cladocera consisted of Bosmina coregoni and appeared to have excellent preservation in the trap assemblages. Moreover, some common littoral Cladocera such as Alonella excisa and Aloha guttata appear to be less well preserved in the fossil assemblages. Large littoral taxa such as Eurycercus lamellatus and Aloha quadrangularis were rare in the trap but relatively common and well preserved in the sediment-water interface. It is suggested that taphonomic processes play a dominant role on deposition of fossil remains of Cladocera and caution should be taken while inferring the past environmental changes whilst using fossil assemblages recovered from the lake centre as a representation of the entire cladoceran community in the lake.展开更多
The Messel oil shale, Germany, was deposited in a maar crater that formed 47 million years ago. Since 1975 the Senckenberg Research Institute in Frankfurt am Main, has conducted systematic scientific excavations of th...The Messel oil shale, Germany, was deposited in a maar crater that formed 47 million years ago. Since 1975 the Senckenberg Research Institute in Frankfurt am Main, has conducted systematic scientific excavations of this oil shale with much success. Besides plants and insects, more than 130 species of well-preserved fossil vertebrates like reptiles, fishes, birds and mammals have been found and have made Messel world-famous. Some examples of these vertebrates are presented.展开更多
Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the Mesozoic.However,the limited information on the taphonomy of hair hi...Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the Mesozoic.However,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time.To address this,we conducted taphonomic experiments to simulate the transformation process of black hair.The changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman spectroscopy.Our results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently stable.The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased.Although the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.展开更多
The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceou...The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.展开更多
The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct species.However,existing methods often rely on the presence of co...The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct species.However,existing methods often rely on the presence of complete eggs and embryo remains,and sedimentological criteria that are only applicable to well-structured sediments.In this study,we introduce an innovative approach to characterize egg accumulations in structureless sediments,where traditional nest structures may not be preserved.Our methodology employs a unique combination of sedimentological,taphonomic,geochemical,and geophysical proxies for the study of egg accumulations.We applied this approach to the egg accumulation from Paimogo(Jurassic,Portugal),traditionally interpreted as a nest.Our findings reveal that the Paimogo egg assemblage is a secondary deposit,resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph clutches.The eggshell vapor conductance results,coupled with sedimentological evidence,suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season,likely during the dry season to prevent the embryos from drowning.This research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless sediments.Our findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms,contributing to our understanding of dinosaur ecology.展开更多
During the climatic fluctuations in the late Late Pleistocene, hominins in China had experienced some significant changes and adaptations in terms of subsistence strategies. Based on the zooarchaeological analyses of ...During the climatic fluctuations in the late Late Pleistocene, hominins in China had experienced some significant changes and adaptations in terms of subsistence strategies. Based on the zooarchaeological analyses of the faunal remains from the Shuidougou site of North China and the Ma'anshan site of South China, the present study demonstratively indicates that the broad-spectrum diet and its closely-related resource intensification for hominins were already at their places roughly at 33–35 cal ka BP. Compared to hominins of earlier period, who would have preferentially exploited large and medium-sized ungulates, hunter-gathers at later period had otherwise incorporated more small-sized animals(especially the quick ones, such as birds and hares) into their diet. Meanwhile, hominins of the later time had also greatly accelerated extractions and exploitations of the nutritional yields from the large and medium-sized animals. However, it seems clear from the current study that there was significant difference regarding the potential mechanisms for the broad-spectrum adaptations of hominins in the late Late Pleistocene of China.展开更多
The study of prehistoric hunter-gatherer subsistence strategies on the Tibetan Plateau is important for understanding the mechanisms and processes of human adaption to high altitude environments.But to date,only a few...The study of prehistoric hunter-gatherer subsistence strategies on the Tibetan Plateau is important for understanding the mechanisms and processes of human adaption to high altitude environments.But to date,only a few Paleolithic sites have been found on the Tibetan Plateau with clear stratigraphy and reliable dating.These sites are mainly distributed in the Qinghai Lake Basin on the northeastern part of the plateau,and the sporadic fauna and flora remains excavated provide limited information about the subsistence strategies of hunter-gatherers.In 2014,relatively abundant animal remains were unearthed in the Lower Cultural Layer (LCL,15400-13100 cal yr BP) of the"151 site"located in the Qinghai Lake Basin,providing important information about human subsistence strategies on the Tibetan Plateau during the Last Deglaciation.Zooarchaeological analysis of these faunal remains indicates that hunter-gatherers at the"151 site"mainly targeted large ungulates of Bos and wild horse/ass,and only brought back the most nutritious parts of animal carcasses including upper and intermediate limb bones,heads,and trunks (ribs and vertebrae).People then processed and consumed the carcasses around single hearths.Our comprehensive analyses of contemporaneous sites in the Qinghai Lake Basin show that a subsistence strategy involving opportunistic hunting of ungulates,high mobility,and short occupation of campsites was used by terminal Pleistocene huntergatherers to adapt to the high-altitude environment on the Tibetan Plateau.This subsistence strategy may have been a first step of gradual hunter-gatherer adaptation to the extreme conditions on the Tibetan Plateau after the Last Glacial Maximum,and laid the foundation for the widespread distribution of hunter-gatherers on the plateau during the Holocene.展开更多
More than ten thousands of bone fragments were recovered from the Lingjing site, Henan Province during 2005 and 2006. In this paper, through the quantification and statistical analyses of the skeletal elements of the ...More than ten thousands of bone fragments were recovered from the Lingjing site, Henan Province during 2005 and 2006. In this paper, through the quantification and statistical analyses of the skeletal elements of the two predominant species in this assemblage, aurochs (Bos primigenius) and horse (Equus caballus), the differential influences and weights of a variety of taphonomic agencies in the formation of the assemblage are assessed respectively. Compared to the natural agencies, hominid hunting and the subsequent disarticulation, slaughtering, and their transport of the bone elements of the prey species are the main factors accounting for the formation of the present assemblage. More importantly, this study initiatively identifies hominid's differential treatment of the bones of aurochs and horse in the Paleolithic record of East Asia and demonstrably suggests that hominids at the site have already practiced sophisticated hunting techniques and subsistence strategies and may be quite familiar with the ecological and anatomical characteristics and nutritional values of the large-sized prey animals and can accordingly take different processing and handling strategies at the hunting site.展开更多
The generation of a DNA profile from skeletal remains is an important part of the identifica-tion process in both mass disaster and unidentified person cases. Since bones and teeth are often the only biological materi...The generation of a DNA profile from skeletal remains is an important part of the identifica-tion process in both mass disaster and unidentified person cases. Since bones and teeth are often the only biological materials remaining after exposure to environmental conditions, intense heat, certain traumatic events and in cases where a significant amount of time has passed since the death of the individual, the ability to purify large quantities of informative DNA from these hard tissues would be beneficial. Since sampling the hard tissues for gen-etic analysis is a destructive process, it is important to understand those environmental and intrinsic factors that contribute to DNA preservation. This will serve as a brief introduction to these topics, since skeletal sampling strategies and molecular taphonomy have been dis-cussed in depth elsewhere. Additionally advances in skeletal DNA extraction and analysis will be discussed. Currently there is great variation in the DNA isolation methods used by laboratories to purify DNA from the hard tissues;however, a standardized set of short tan-dem repeat (STR) loci is analyzed by many US laboratories to allow for comparisons across samples and jurisdictions. Recent advances have allowed for the generation of DNA profiles from smaller quantities of template DNA and have expanded the number of loci analyzed for greater discriminatory power and predictions regarding the geographic ancestry and phenotype of the individual. Finally, utilizing databases and expanding the number of com-parison samples will be discussed in light of their role in the identification process.展开更多
The Early Cambrian Chengjiang Biota of China has preserved many species of vermiform animals in exquisite detail,which provide a unique window into the origin and early evolution of different vermiform phyla.This arti...The Early Cambrian Chengjiang Biota of China has preserved many species of vermiform animals in exquisite detail,which provide a unique window into the origin and early evolution of different vermiform phyla.This article reviews and discusses the forty-five Chengjiang vermiform animals discovered so far,and specifically comments on the phylogeny,modes of life,evolutionary significance as well as existing debates concerning the Chengjiang priapulid and lobopodian phyla.This article analyzes existing problems with Chengjiang vermiform morphological research and highlights various factors that affect the final preserved fossil morphology,including taphonomy and shape change caused by vermiform movement,as well as proposing that Anningvermis multispinosa and Corynetis brevis are synonymous.Chengjiang vermiform animals displayed a great diversity of morphologies and ecological roles,which is significant for understanding the origin and evolution of early metazoans;the potential for future research is enormous but needs to be broadened by interdisciplinary work involving taphonomy,geochemistry,cladistics,and genetics.展开更多
基金supported by the State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences(No.223115)to Zhongwu Lan.
文摘Taphonomy and paleoecology(biological behavior)of the Early Cretaceous fish fossils are poorly described.This study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Mesozoic strata of western Liaoning Province,NE China.The XRD analysis shows that gismondine is the dominant clay minerals that could have contributed to the preservation of Lycoptera fossils and microbial mat fragments in the fossil-bearing horizon.Gismondine may have formed under volcanism-related hydrothermal regime that was transformed from crystal and lithic fragments.Theμ-XRF imaging analysis shows a dominant chemical composition of Al,Si,P,S,Rh,K,Ca,Ti,C,Cr,Mn,Fe,Ni,among which P,Ca,C and S are enriched in the fish skeleton in comparison to the matrix.This suggests a dominant apatite composition for the fish skeleton.Hydrothermal influence did not smear off these organic signals probably because of protection of gismondine.The coexistance of C and S with Ni is assumed to represent recovered primary productivity following volcanic explosions and toxic gas emissions.The head of juvenile fish stays close to the body of adult fish.Pending further discoveries,such phenomenon is interpreted to suggest that adult fish actively protected juvenile fish in the presence of environmental pressures such as anoxia and deterioration of water quality induced by volcanism.Ocean acidification and hypoxia in association with volcanism created a harmful environment causing mass extinction of fish.The adult Lycoptera protected their juveniles by its body at the moment before death.Such biological behavior will be increasingly reported given the wide occurrence of Lycoptera in Mesozoic strata.
文摘Through taphonomical analyses of Crassostrea shell beds included in several Japanese Cretaceous strata, paleoecological and sedimentological significance of intertidal muddy and sandy bottom dwelling oysters are examined. The Upper Cretaceous Crassostrea shell beds show a variety of modes of occurrence, lithological changes and sedimentary structure, suggesting composite formative, paleoecological and sedimentary processes. Crassostrea seems to have adapted from muddy substratum during early Cretaceous to coarser sandier substratum often influenced by physical turbulence such as tidal currents and waves during the mid-Cretaceous time, associated with increasing in shell size and thickness, and colony dimension.
文摘Jehol Biota in western Liaoning and northern Hebei has been a hot topic of global concern,a large number of exquisite fossils were found in Yixian group Sihetun,such as Sinosauropteryx,Protarchaeopteryx, Caudipteryx and Confuciusornis.Scientists consider the discovering of Sinosauropteryx discovered so far as the earliest ancestor of birds.According to the dates of root layer,we can see warm and humid,lakes
文摘Forensic taphonomy as a discipline requires standardization to satisfy Daubert criteria for sci-entific data to be admissible in court.In response,there has been a shift towards quantifica-tion of methodology and estimating the postmortem interval.Despite these advances,there are still biases and limitations within the discipline not explicitly addressed in the early stages of experimental design nor in final published works.In this article,unresolved debates with respect to the conductance and reporting of forensic taphonomic research are reviewed,beginning with the nature of experimental cadavers,human or animal analogues and their body size,and second,the forensic realism of experimental setups,specifically with respect to caging,clothing and number of carcases.Pigs,albeit imperfect,are a good model to gain a general idea of the trends that may be seen in humans in subsequent validation studies in facilities where human donors are available.To date,there is no consen-sus among taphonomists on the extent of the effect that body mass has on decomposition progression.More research is required with both human cadavers and non-human analogues that builds on our current knowledge of forensic taphonomy to answer these nagging questions.This will enable the discipline to make the reliable assumption that pigs and donor decomposition data can be applied to homicide cases.A suite of experimental design aspects is suggested to ensure systematic and standardized data collection across differ-ent biogeoclimatic circumstances to identify and quantify the effects of potential confounding variables.Such studies in multiple,varied biogeographic circumstances with standardized protocols,equipment and carrion will facilitate independent global validation of patterns.These factors are reviewed to show the need for adjustments in experimental design to ensure relevance and applicability of data within locally realistic forensic situations.The initiation of a global decomposition data network for forensic taphonomists is recommended.
文摘Abstract The taphonomy of fishes living in lacustrine environments has been extensively studied in both the laboratory and the fossil record;the taphonomy of marine fishes,however,is poorly known.Triassic marine fishes with heavy ganoid and cosmoid scales,which provided protection from rapid taphonomic loss,offer a means to examine marine fish taphonomy in the fossil record.Four genera of Early Triassic fishes(the ray-finned actinopterygians Albertonia,Bobasatrania,Boreosomus,and the lobe-finned coelacanth(sarcopterygian),Whiteia)from the Wapiti Lake,British Columbia locality of the Lower Triassic Sulphur Mountain Formation were examined in order to gain a better understanding of the taphonomy of fish in marine environments,determine ambient environmental conditions in the region during the Early Triassic,and ascertain the habitat and mode of life of the fish.Results indicate that environmental conditions that contributed to the preservation of the fossil fishes of the current study included deposition in deep,quiet waters,which reduced the odds of disarticulation,colder waters under higher pressure,which slowed decay and limited postmortem floatation,and waters that were anoxic,which discouraged predators and scavengers.In addition,the thickness of the primitive ganoid and cosmoid scales of the fossil fishes also increased their preservation potential.Taphonomic,physiological and environmental indicators suggest that Whiteia,Albertonia,and possibly Bobasatrania lived in deep,cold waters near the oxygen minimum zone,while Boreosomus lived higher in the water column.While the anatomical and physiological characteristics of modern fishes will likely continue to inhibit marine taphonomy studies,examination of ancient fish,particularly those with ganoid or cosmoid scales,may provide future avenues of research to gain a better understanding of marine fish taphonomy and provide a powerful tool to examine ancient fish behavior and their environment.
基金supported by the NationalNatural Science Foundation of China(Grant Nos.40772008 and 40572003)the Research Fund for DoctoralProgram of High Education(Grant No.20060001059)State Key Laboratory of Paleobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,ChineseAcademy of Sciences(Grant No.083101)
文摘The exquisitely preserved fossil embryos of Markuelia recovered from the limestones of the Middle Cambrian Haoqiao Formation and Upper Cambrian Bitiao formation in western Hunan, South China are described and illustrated in detail for the first time. A new species Markuelia elegans sp. nov. is established based mainly on embryos from the Upper Cambrian. A few of animal's resting eggs, which are comparable with those of the Ediacaran Doushantuo Formation, have been also found in the Upper Cambrian of western Hunan. The membrane of one egg from the uppermost Cambrian has been replaced by pyrite and the overgrowth of the pyrite crystals exhibits a unique inorganic pattern termed herein 'Pseudoembryo'. The taphonomic setting in deeper water with possible strong reducing conditions promoted the excellent preservation for the Markuelia specimens. The study of Markuelia provides not only constraint on the anatomy, affinity, embryonic development and phylogenetic significance of this wormlike animal and but also opens a new window onto the evolution and development of the earliest animals.
基金supported by a scholarship from the Instituto Geologico y Minero de Espana(IGME),an APIF grant of the University of Barcelona,and a FPI grant from the Spanish Ministry of Science and Technology,respectivelya contribution of the IGME Project 491-CANOA 35015"Investigacion cientifica y tecnica de la Cueva de E1 Soplao y su entorno geologico"+1 种基金the projects CGL2008-/01237BTE from the MICINN,CGL2008- 00550/BTE:"Amber of the Cretaceous of Spain:A multidisciplinary study"the ANR Project AMBRACE BLAN07-1-184190
文摘El Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain (Cantabria), has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. Relevant data provided herein for biogeochemistry of the amber, palynology, taphonomy and arthropod bioinclusions complement those previously published. This set of data suggests at least two botanical sources for the amber of El Soplao deposit. The first (type A amber) strongly supports a source related to Cheirolepidiaceae, and the second (type B amber) shows non-specific conifer biomarkers. Comparison of molecular composition of type A amber with Frenelopsis leaves (Cheirolepidiaceae) strongly suggests a biochemical affinity and a common botanical origin. A preliminary palynological study indicates a regional high taxonomical diversity, mainly of pteridophyte spores and gymnosperm pollen grains. According to the preliminary palynological data, the region was inhabited by conifer forests adapted to a dry season under a subtropical climate. The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter, and subsequent great accumulation of amber plus plant cuticles. In addition, for the first time in the fossil record, charcoalified plant fibers as bioinclnsions in amber are reported. Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber. Lastly, new findings of insect bioiuclusions, some of them uncommon in the fossil record or showing remarkable adaptations, are reported. In conclusion, a documented scenario for the origin of the El Soplao amber outcrop is provided.
基金funded jointly by National 973 Project (2012CB821901)the National Nature Sciences Foundation of China (41372011,41372010)
文摘Fossil ferns are abundant and diverse in the Permian Cathaysian Flora of Shanxi, North China. Although plants assemblages of the Carboniferous and Permian have been extensively investigated, their palaeoecology and especially the paleoecology of ferns has not been studied in detail. Recent reinvestigation of Oligocarpia gothanii has revealed its growth habit and cloning reproduction strategy, but most previous studies lack integrated sedimentological and taphonomic data. In this study, new materials of O. gothanii have been collected from a floodplain setting in the middle Permian Lower Shihhotse Formation of southeastern Shanxi. These plant fossils were found in a lenticular claystone associated with rooting structures. They are characterized by aphlebia at the base of the penultimate rachis. Sedimentological, taphonomic and morphological analyses were conducted to understand the growth habit and ecology of the fern. The result indicates that the Oligocarpia gothanii had a prostrate, ground cover growth habit, and was dominant in pioneer floras that colonized disturbed floodplains.
文摘Taphonomy refers primarily to the study of processes between death and final burial of an organism or a group of organisms, including both taphonomic loss and taphonomic gain. Taphofacies refers to the taphonomic traits, which include the taphonomic attributes of all fossils and the lithologic features of their enclosing rocks. Taphofacies is different from lithofacies; as a taphonomic environmental setting or taphonomic condition, it is more useful than the stratigraphic body of rock. Based on the features of fossil preservation integrated with stratigraphic, sedimentologic and paleontologic evidence from Devonian of Longmenshan area, it is distinguished and described 11 taphofacies models. For convenience in the field, the name of each taphofacies is divided into taphonomic and lithologic traits. The spatial relations between each taphofacies and the taphofacies with the benthic assemblages 1-6 are discussed.
基金financially supported by the National Natural Science Foundation of China(grant nos.41890843 and 41920104009)the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant No.311021003)。
文摘Silica-phosphatic nodules are abundant in black shales of the Yanjiahe Formation in the Three Gorges Area of South China,which is correlated to the Fortunian Stage,Terreneuvian Series,Cambrian System.The nodules are rich in small shelly fossils and hence attract the attention of numerous paleontologists and sedimentary geologists.However,the genesis of the nodules and the preservation of the small shelly fossils are poorly understood.Here we analyze morphological,structural,mineralogical and chemical features of the nodules in multiscale using a combination of micro-X-ray fluorescence spectroscopy,X-ray diffraction,scanning electron microscopy and confocal laser Raman spectroscopy.Results reveal that nodules are concentric in chemical and mineralogical compositions,comprising a silica-phosphatic core encrusted sequentially by a phosphatic zone,a siliceous zone and a very thin pyrite outer rim.The black shales hosting the nodules demonstrate a laminated texture of alternating clayey and silty laminae,which were respectively deposited in sulfidic/less sulfidic,high/low production,intense/weak chemical weathering conditions.The phosphogenesis of the nodules resulted in the phosphatization of small shelly fossils,which prevented the fossils from being dissolved during diagenesis,whereas the silica encrustation sealed the fossils within the nodules and thus protected the fossils from alteration by deep burial and surface weathering.
基金supported by the ORS Award to Giri Kattel, ENSIS Ltd Trust Fund,Department of Geography and UCL Graduate School Research Scholarships
文摘Representativity of biota in the biosphere also have similar significance in the lithosphere after their death. Recently, taphonomic representation of biota in the lithosphere has been widely used for minimizing the biases in palaeo-environmental reconstructions including global climate change. In September 2001, a sediment trap was installed at the central area of the Loch Coire Fionnaraich (LCFR), a small, oligotrophic mountain loch in northwest Scotland for a taphonomic study of cladoceran zooplankton. The trap was emptied on a seasonal basis, where an average 0.14 g dry material was recovered in each season, January, May and August 2002 respectively. A sediment core was also taken from near the sediment trap location. The top 0.5 cm section, the 'core' was used for a comparative study with the trap sediment samples. The planktonic Cladocera consisted of Bosmina coregoni and appeared to have excellent preservation in the trap assemblages. Moreover, some common littoral Cladocera such as Alonella excisa and Aloha guttata appear to be less well preserved in the fossil assemblages. Large littoral taxa such as Eurycercus lamellatus and Aloha quadrangularis were rare in the trap but relatively common and well preserved in the sediment-water interface. It is suggested that taphonomic processes play a dominant role on deposition of fossil remains of Cladocera and caution should be taken while inferring the past environmental changes whilst using fossil assemblages recovered from the lake centre as a representation of the entire cladoceran community in the lake.
文摘The Messel oil shale, Germany, was deposited in a maar crater that formed 47 million years ago. Since 1975 the Senckenberg Research Institute in Frankfurt am Main, has conducted systematic scientific excavations of this oil shale with much success. Besides plants and insects, more than 130 species of well-preserved fossil vertebrates like reptiles, fishes, birds and mammals have been found and have made Messel world-famous. Some examples of these vertebrates are presented.
基金supported by the National Natural Science Foundation of China(Grant Nos.42288201&41922011)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB26000000)the Fundamental Research Funds for the Central Universities(Grant No.0206-14380219)。
文摘Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the Mesozoic.However,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time.To address this,we conducted taphonomic experiments to simulate the transformation process of black hair.The changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman spectroscopy.Our results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently stable.The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased.Although the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.
基金financially supported by the National Natural Science Foundation of China (Grant Nos.42102127, 42172117)the Natural Science Foundation of Shandong Province (Grant No. ZR2021QD087)+1 种基金the Chinese Postdoctoral Science Foundation (Grant No.2021M702019)the SDUST Research Fund,Shandong University of Science and Technology (Grant No.2018TDJH101)。
文摘The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.
基金supported the PLEC2021-008203 project and RYC2021-034473-Ifunded by MCIN/AEI/10.13039/501100011033+4 种基金by the European Union"NextGenerationEU"/PRTRFundação para a Ciência e Tecnologia(FCT-MCTES)of Portugal(projects PTDC/CTA-PAL/31656/2017 and PTDC/CTA-PAL/2217/2021)Research Unit GeoBioTec UIDB/04035/2020Also,the work is part of the Carmen Nunez-Lahuerta is supported by FJC2020-044561-I-MCIN,co-financed by the NextGeneration EU/PRTR.
文摘The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct species.However,existing methods often rely on the presence of complete eggs and embryo remains,and sedimentological criteria that are only applicable to well-structured sediments.In this study,we introduce an innovative approach to characterize egg accumulations in structureless sediments,where traditional nest structures may not be preserved.Our methodology employs a unique combination of sedimentological,taphonomic,geochemical,and geophysical proxies for the study of egg accumulations.We applied this approach to the egg accumulation from Paimogo(Jurassic,Portugal),traditionally interpreted as a nest.Our findings reveal that the Paimogo egg assemblage is a secondary deposit,resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph clutches.The eggshell vapor conductance results,coupled with sedimentological evidence,suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season,likely during the dry season to prevent the embryos from drowning.This research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless sediments.Our findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms,contributing to our understanding of dinosaur ecology.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA05130302)the Key Research Program of the Chinese Academy of Sciences (Grant No. KZZD-EW-15)the National Natural Science Foundation of China (Grant No. 41302017)
文摘During the climatic fluctuations in the late Late Pleistocene, hominins in China had experienced some significant changes and adaptations in terms of subsistence strategies. Based on the zooarchaeological analyses of the faunal remains from the Shuidougou site of North China and the Ma'anshan site of South China, the present study demonstratively indicates that the broad-spectrum diet and its closely-related resource intensification for hominins were already at their places roughly at 33–35 cal ka BP. Compared to hominins of earlier period, who would have preferentially exploited large and medium-sized ungulates, hunter-gathers at later period had otherwise incorporated more small-sized animals(especially the quick ones, such as birds and hares) into their diet. Meanwhile, hominins of the later time had also greatly accelerated extractions and exploitations of the nutritional yields from the large and medium-sized animals. However, it seems clear from the current study that there was significant difference regarding the potential mechanisms for the broad-spectrum adaptations of hominins in the late Late Pleistocene of China.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41771225 & 41620104007)the Primary Supports for Scientific Research of Lanzhou University (Grant Nos. LZUJBKY-2016-254, LZUJBKY-2016-279 & LZUJBKY-2018-144)China Scholarship Council
文摘The study of prehistoric hunter-gatherer subsistence strategies on the Tibetan Plateau is important for understanding the mechanisms and processes of human adaption to high altitude environments.But to date,only a few Paleolithic sites have been found on the Tibetan Plateau with clear stratigraphy and reliable dating.These sites are mainly distributed in the Qinghai Lake Basin on the northeastern part of the plateau,and the sporadic fauna and flora remains excavated provide limited information about the subsistence strategies of hunter-gatherers.In 2014,relatively abundant animal remains were unearthed in the Lower Cultural Layer (LCL,15400-13100 cal yr BP) of the"151 site"located in the Qinghai Lake Basin,providing important information about human subsistence strategies on the Tibetan Plateau during the Last Deglaciation.Zooarchaeological analysis of these faunal remains indicates that hunter-gatherers at the"151 site"mainly targeted large ungulates of Bos and wild horse/ass,and only brought back the most nutritious parts of animal carcasses including upper and intermediate limb bones,heads,and trunks (ribs and vertebrae).People then processed and consumed the carcasses around single hearths.Our comprehensive analyses of contemporaneous sites in the Qinghai Lake Basin show that a subsistence strategy involving opportunistic hunting of ungulates,high mobility,and short occupation of campsites was used by terminal Pleistocene huntergatherers to adapt to the high-altitude environment on the Tibetan Plateau.This subsistence strategy may have been a first step of gradual hunter-gatherer adaptation to the extreme conditions on the Tibetan Plateau after the Last Glacial Maximum,and laid the foundation for the widespread distribution of hunter-gatherers on the plateau during the Holocene.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant Nos. KZCX2-YW-Q1-04 and KZCX2-EW-QN110)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA05130302)the National Natural Science Foundation of China (Grant Nos. 40602006 and 40872115)
文摘More than ten thousands of bone fragments were recovered from the Lingjing site, Henan Province during 2005 and 2006. In this paper, through the quantification and statistical analyses of the skeletal elements of the two predominant species in this assemblage, aurochs (Bos primigenius) and horse (Equus caballus), the differential influences and weights of a variety of taphonomic agencies in the formation of the assemblage are assessed respectively. Compared to the natural agencies, hominid hunting and the subsequent disarticulation, slaughtering, and their transport of the bone elements of the prey species are the main factors accounting for the formation of the present assemblage. More importantly, this study initiatively identifies hominid's differential treatment of the bones of aurochs and horse in the Paleolithic record of East Asia and demonstrably suggests that hominids at the site have already practiced sophisticated hunting techniques and subsistence strategies and may be quite familiar with the ecological and anatomical characteristics and nutritional values of the large-sized prey animals and can accordingly take different processing and handling strategies at the hunting site.
文摘The generation of a DNA profile from skeletal remains is an important part of the identifica-tion process in both mass disaster and unidentified person cases. Since bones and teeth are often the only biological materials remaining after exposure to environmental conditions, intense heat, certain traumatic events and in cases where a significant amount of time has passed since the death of the individual, the ability to purify large quantities of informative DNA from these hard tissues would be beneficial. Since sampling the hard tissues for gen-etic analysis is a destructive process, it is important to understand those environmental and intrinsic factors that contribute to DNA preservation. This will serve as a brief introduction to these topics, since skeletal sampling strategies and molecular taphonomy have been dis-cussed in depth elsewhere. Additionally advances in skeletal DNA extraction and analysis will be discussed. Currently there is great variation in the DNA isolation methods used by laboratories to purify DNA from the hard tissues;however, a standardized set of short tan-dem repeat (STR) loci is analyzed by many US laboratories to allow for comparisons across samples and jurisdictions. Recent advances have allowed for the generation of DNA profiles from smaller quantities of template DNA and have expanded the number of loci analyzed for greater discriminatory power and predictions regarding the geographic ancestry and phenotype of the individual. Finally, utilizing databases and expanding the number of com-parison samples will be discussed in light of their role in the identification process.
基金supported by National Natural Science Foundation of China (Grant No. 40730211)National Basic Research Programme of China (Grant No. 206CB806400)Natural Science Foundation of Department of Science and Technology of Yunnan Province (Grant No. 2005D002Z)
文摘The Early Cambrian Chengjiang Biota of China has preserved many species of vermiform animals in exquisite detail,which provide a unique window into the origin and early evolution of different vermiform phyla.This article reviews and discusses the forty-five Chengjiang vermiform animals discovered so far,and specifically comments on the phylogeny,modes of life,evolutionary significance as well as existing debates concerning the Chengjiang priapulid and lobopodian phyla.This article analyzes existing problems with Chengjiang vermiform morphological research and highlights various factors that affect the final preserved fossil morphology,including taphonomy and shape change caused by vermiform movement,as well as proposing that Anningvermis multispinosa and Corynetis brevis are synonymous.Chengjiang vermiform animals displayed a great diversity of morphologies and ecological roles,which is significant for understanding the origin and evolution of early metazoans;the potential for future research is enormous but needs to be broadened by interdisciplinary work involving taphonomy,geochemistry,cladistics,and genetics.