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1.
Xu X  Norell MA  Kuang X  Wang X  Zhao Q  Jia C 《Nature》2004,431(7009):680-684
Tyrannosauroids are one of the last and the most successful large-bodied predatory dinosaur groups, but their early history remains poorly understood. Here we report a new basal tyrannosauroid from the Early Cretaceous Yixian Formation of western Liaoning, China, which is small and gracile and has relatively long arms with three-fingered hands. The new taxon is the earliest known unquestionable tyrannosauroid found so far. It shows a mosaic of characters, including a derived cranial structure resembling that of derived tyrannosauroids and a primitive postcranial skeleton similar to basal coelurosaurians. One of the specimens also preserves a filamentous integumentary covering similar to that of other coelurosaurian theropods from western Liaoning. This provides the first direct fossil evidence that tyrannosauroids had protofeathers.  相似文献   

2.
Padian K  Dial KP 《Nature》2005,438(7066):E3; discussion E3-E3; discussion E4
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3.
Xu X  Tan Q  Wang J  Zhao X  Tan L 《Nature》2007,447(7146):844-847
An evolutionary trend of decreasing size is present along the line to birds in coelurosaurian theropod evolution, but size increases are seen in many coelurosaurian subgroups, in which large forms are less bird-like. Here we report on a new non-avian dinosaur, Gigantoraptor erlianensis, gen. et sp. nov., from the Late Cretaceous Iren Dabasu Formation of Nei Mongol, China. Although it has a body mass of about 1,400 kg, a phylogenetic analysis positions this new taxon within the Oviraptorosauria, a group of small, feathered theropods rarely exceeding 40 kg in body mass. A histological analysis suggests that Gigantoraptor gained this size by a growth rate considerably faster than large North American tyrannosaurs such as Albertosaurus and Gorgosaurus. Gigantoraptor possesses several salient features previously unknown in any other dinosaur and its hind limb bone scaling and proportions are significantly different from those of other coelurosaurs, thus increasing the morphological diversity among dinosaurs. Most significantly, the gigantic Gigantoraptor shows many bird-like features absent in its smaller oviraptorosaurian relatives, unlike the evolutionary trend seen in many other coelurosaurian subgroups.  相似文献   

4.
Göhlich UB  Chiappe LM 《Nature》2006,440(7082):329-332
Small Late Jurassic theropod dinosaurs are rare worldwide. In Europe these carnivorous dinosaurs are represented primarily by only two skeletons of Compsognathus, neither of which is well preserved. Here we describe a small new theropod dinosaur from the Late Jurassic period of Schamhaupten in southern Germany. Being exquisitely preserved and complete from the snout to the distal third of the tail, the new fossil is the best-preserved predatory, non-avian dinosaur in Europe. It possesses a suite of characters that support its identification as a basal coelurosaur. A cladistic analysis indicates that the new taxon is closer to maniraptorans than to tyrannosauroids, grouping it with taxa often considered to be compsognathids. Large portions of integument are preserved along its tail. The absence of feathers or feather-like structures in a fossil phylogenetically nested within feathered theropods indicates that the evolution of these integumentary structures might be more complex than previously thought.  相似文献   

5.
An exceptionally preserved Lower Cretaceous ecosystem   总被引:52,自引:0,他引:52  
Zhou Z  Barrett PM  Hilton J 《Nature》2003,421(6925):807-814
Fieldwork in the Early Cretaceous Jehol Group, northeastern China has revealed a plethora of extraordinarily well-preserved fossils that are shaping some of the most contentious debates in palaeontology and evolutionary biology. These discoveries include feathered theropod dinosaurs and early birds, which provide additional, indisputable support for the dinosaurian ancestry of birds, and much new evidence on the evolution of feathers and flight. Specimens of putative basal angiosperms and primitive mammals are clarifying details of the early radiations of these major clades. Detailed soft-tissue preservation of the organisms from the Jehol Biota is providing palaeobiological insights that would not normally be accessible from the fossil record.  相似文献   

6.
A long-tailed,seed-eating bird from the Early Cretaceous of China   总被引:23,自引:0,他引:23  
Zhou Z  Zhang F 《Nature》2002,418(6896):405-409
The lacustrine deposits of the Yixian and Jiufotang Formations in the Early Cretaceous Jehol Group in the western Liaoning area of northeast China are well known for preserving feathered dinosaurs, primitive birds and mammals. Here we report a large basal bird, Jeholornis prima gen. et sp. nov., from the Jiufotang Formation. This bird is distinctively different from other known birds of the Early Cretaceous period in retaining a long skeletal tail with unexpected elongated prezygopophyses and chevrons, resembling that of dromaeosaurids, providing a further link between birds and non-avian theropods. Despite its basal position in early avian evolution, the advanced features of the pectoral girdle and the carpal trochlea of the carpometacarpus of Jeholornis indicate the capability of powerful flight. The dozens of beautifully preserved ovules of unknown plant taxa in the stomach represents direct evidence for seed-eating adaptation in birds of the Mesozoic era.  相似文献   

7.
The recently discovered definite giant fleas from the Middle Jurassic Daohugou fauna and the Early Cretaceous Jehol fauna of northeastern China represent significant evidence for understanding ectoparasitism in the Mesozoic as well as the evolution of these giant blood feeders with their putative hosts (i.e. hairy or feathered vertebrates). On the basis of seven well-preserved specimens from Daohugou and Huangbanjigou we analyse the systematic classification of these primitive fleas, establishing two new genera and three new species as Pseudopulex wangi sp. nov., Hadropsylla sinica gen. et sp. nov., and Tyrannopsylla beipiaoensis gen. et sp. nov. All of them are assigned to the extinct siphonapteran family Pseudopulicidae, while the Early Cretaceous genus Tarwinia is transferred to Tarwiniidae fam. nov. The basal morphological disparities of Siphonaptera in the Mesozoic are evidenced by the occurrence of at least three distinct groups (pseudopulicids, tarwiniids, and saurophthirids). These disparate morphologies likely indicate adaptations to different hosts.  相似文献   

8.
"华丽"一词在当代语言生活中呈现出丰富的变异现象.首先是它趋于抽象化,着重体现为其词义发展和由之带来的搭配对象的变化.其次是该词的"状语化"演变,包括其衍生的修饰动词、充当状语的语法功能.从言内理据和言外理据两个角度分析了其蜕变的成因,并对其未来走向作出宏观预测.  相似文献   

9.
First ceratopsid dinosaur from China and its biogeographical implications   总被引:2,自引:0,他引:2  
Ceratopsid dinosaurs represent one of the best known dinosaur groups in the Late Cretaceous, and their unquestionable fossil re-cords are exclusively restricted to western North America.Here we report a new ceratopsid dinosaur, Sinoceratops zhuchengensis gen.et sp.nov., from the Upper Cretaceous Wangshi Group of Zhucheng, Shandong Province, China.Cladistic analysis places this new taxon as the only known ceratopsid from outside North America, in a basal position within the Centrosaurinae.It is con-siderably...  相似文献   

10.
Earliest Asian discoglossid frog from western Liaoning   总被引:2,自引:0,他引:2  
Based on a superbly preserved skeleton, a new anuran taxon has been named and described from the Yixian Formation (Upper Jurassic/Lower Cretaceous), Liaoning Province, northeastern China. This discovery documents the first discoglossid fossil from China, the earliest record of the group in Asia, and the only second Mesozoic discoglossid known from fully articulated material in the world. The family Discoglossidae is widely perceived as a primitive anuran group, but has no definite fossils found in collaboration with their recent distribution in Asia. The new discovery from Liaoning extends the temporal range of the group in Asia back at least 120 million years, and provides valuable fossil material for study of anatomical details of early discoglossids, as well as of historical distribution of this primitive anuran group.  相似文献   

11.
Study of fossil birds in China was first conducted by western scholars in last century, and extensive study of Cenozoic birds by Chinese scholars since the 1970s. However, it is the finding of Mesozoic birds, mostly from northeast China since the 1990s, that has become the focus and highlight of paleornithology of China. Enantiornithine birds from the Late Jurassic-Early Cretaceous of China provide the most complete record of the early evolution of this extinct group. The co-existence of the most primitive ornithurine bird Liaoningornis with the oldest known Confuciusornis indicates an earlier and more significant diversification of birds than previously recognized. Evidence from the Chinese Mesozoic birds seems to support the arboreal hypothesis of the origin of avian flight. Despite the controversy, the recent discovery of various feathered dinosaurs in China may provide the most compelling evidence for the hypothesis of the dinosaurian origin of birds.  相似文献   

12.
Two fossil dragonflies from the Upper Jurassic to Lower Cretaceous Yixian Formation in Liutiaogou Village, Ningcheng County,Inner Mongolia, China are described and illustrated. They are assigned to two new genera and species, I.e., Sophoaeschna frigida gen.et sp. Nov. And Falsisophoaeschna generalis gen. Et sp. Nov. Within the family Gomphaeschnidae Tillyard & Fraser, 1940. This is the first report of Odonata from Yixian Formation in Inner Mongolia and the second record of fossil Gomphaeschnidae from China.  相似文献   

13.
The earliest known eutherian mammal   总被引:23,自引:0,他引:23  
Ji Q  Luo ZX  Yuan CX  Wible JR  Zhang JP  Georgi JA 《Nature》2002,416(6883):816-822
The skeleton of a eutherian (placental) mammal has been discovered from the Lower Cretaceous Yixian Formation of northeastern China. We estimate its age to be about 125 million years (Myr), extending the date of the oldest eutherian records with skull and skeleton by about 40 50 Myr. Our analyses place the new fossil at the root of the eutherian tree and among the four other known Early Cretaceous eutherians, and suggest an earlier and greater diversification of stem eutherians that occurred well before the molecular estimate for the diversification of extant placental superorders (104 64 Myr). The new eutherian has limb and foot features that are known only from scansorial (climbing) and arboreal (tree-living) extant mammals, in contrast to the terrestrial or cursorial (running) features of other Cretaceous eutherians. This suggests that the earliest eutherian lineages developed different locomotory adaptations, facilitating their spread to diverse niches in the Cretaceous.  相似文献   

14.
中国南方大地构造演化及其对油气的控制   总被引:28,自引:0,他引:28  
按照板块构造理论及活动论、阶段论的思想,大致以中晚三叠世为界,将中国南方自震旦纪以来大地构造演化历史划分成海相盆地演化阶段(Z-T2)及陆相盆地演化阶级(T3-Q)两大阶段;又可进一步细分为扬子克拉通及其周缘裂谷盆地(Z-1q)、裂谷-克拉通-被动大陆边缘盆地(1c-O1)、被动陆缘-克拉通-前陆盆地(O2-S)、加里东运动(S末)、裂谷-克拉通盆地(D-T1)、克拉通残留海盆-弧后(浊积)盆地(T2)、印支运动(T2-T3)、华北-华南板块焊合、古特提斯封闭与前陆盆地的形成(T3-J2)、压扭背景下的改造作用及拉分盆地的形成(J3-K1)、伸展-裂陷盆地的形成(K2-E)、喜马拉雅运动(E末-N初)及披盖性构造层的形成(N-Q)12个阶段。特别是对南方自中晚三叠世以来的大地构造演化及其对现存油气的控制作用进行了系统研究,提出了晚侏罗世-早白垩世燕山运动对南方中生界、古生界原生油气藏的保存与破坏起到了决定性作用及燕山、喜马拉雅运动控制了现今南方原生、次生及再生烃(二次生烃)油气藏分布的新观点。  相似文献   

15.
In different opinions, the stratigraphic time of the feathered dinosaurs and early birds in Sihetun and its neighboring areas in Beipiao, western Liaoning is appointed to different epoches of eras, such as Late Jurassic, Early Cretaceous and Late Jurassic-Early Cretaceous. Even the recently dating data are still very different. This note first reported the U-Pb age of (125.2±0.9) Ma of zircon separated from tuff of Sihetun vertebrates horizon. The age reveals that Sihetun vertebrate belongs to Early Cretaceous. The method is more objective, because of the strong ability of disturbance resistance and high U-Pb blocking temperature of zircons.  相似文献   

16.
In different opinions, the stratigraphic time of the feathered dinosaurs and early birds in Sihetun and its neighboring areas in Beipiao, western Liaoning is appointed to different epoches of eras, such as Late Jurassic, Early Cretaceous and Late Jurassic-Early Cretaceous. Even the recently dating data are still very different. This note first reported the U-Pb age of (125.2±0.9) Ma of zircon separated from tuff of Sihetun vertebrates horizon. The age reveals that Sihetun vertebrate belongs to Early Cretaceous. The method is more objective, because of the strong ability of disturbance resistance and high U-Pb blocking temperature of zircons.  相似文献   

17.
Two fossil dragonflies from the Upper Jurassic to Lower Cretaceous Yixian Formation in Liutiaogou Village, Ningcheng County, Inner Mongolia, China are described and illustrated. They are assigned to two new genera and species, i.e., Sophoaeschna frigida gen. et sp. nov. and Falsisophoaeschna generalis gen. et sp. nov. within the family Gomphaeschnidae Tillyard & Fraser, 1940. This is the first report of Odonata from Yixian Formation in Inner Mongolia and the second record of fossil Gomphaeschnidae from China.  相似文献   

18.
Two fossil dragonflies from the Upper Jurassic to Lower Cretaceous Yixian Formation in Liutiaogou Village, Ningcheng County, Inner Mongolia, China are described and illustrated. They are assigned to two new genera and species, i.e., Sophoaeschna frigida gen. et sp. nov. and Falsisophoaeschna generalis gen. et sp. nov. within the family Gomphaeschnidae Tillyard & Fraser, 1940. This is the first report of Odonata from Yixian Formation in Inner Mongolia and the second record of fossil Gomphaeschnidae from China.  相似文献   

19.
Wang X  Kellner AW  Zhou Z  Campos Dde A 《Nature》2005,437(7060):875-879
New specimens and an analysis of the Jehol pterosaur faunae of northeastern China show an unexpected diversity of flying reptile groups in terrestrial Cretaceous ecosystems. Here we report two new pterosaurs that are referred to European groups previously unknown in deposits of northeastern China. Feilongus youngi, from the Yixian Formation, is closely related to the Gallodactylidae and is distinguished by the presence of two independent sagittal crests and a protruding upper jaw. Nurhachius ignaciobritoi, from the Jiufotang Formation, has teeth formed by labiolingually compressed triangular crowns, only previously reported in Istiodactylus latidens from England. With these new discoveries, the Jehol pterosaurs show a wide range of groups including both primitive and derived forms that are not matched by any other deposit in the world. The discoveries also document the turnover of pterosaur faunae, with the primitive Anurognathidae and early archaeopterodactyloids being replaced by derived pterodactyloids. Furthermore, these deposits offer an opportunity to examine the interaction and competition between birds and pterosaurs--it indicates that the avian fauna during the Lower Cretaceous (and possibly most of the Mesozoic) dominated terrestrial, inland regions, whereas pterosaurs were more abundant in coastal areas.  相似文献   

20.
Sander PM  Mateus O  Laven T  Knötschke N 《Nature》2006,441(7094):739-741
Sauropod dinosaurs were the largest animals ever to inhabit the land, with truly gigantic forms in at least three lineages. Small species with an adult body mass less than five tonnes are very rare, and small sauropod bones generally represent juveniles. Here we describe a new diminutive species of basal macronarian sauropod, Europasaurus holgeri gen. et sp. nov., and on the basis of bone histology we show it to have been a dwarf species. The fossils, including excellent skull material, come from Kimmeridgian marine beds of northern Germany, and record more than 11 individuals of sauropods 1.7 to 6.2 m in total body length. Morphological overlap between partial skeletons and isolated bones links all material to the same new taxon. Cortical histology of femora and tibiae indicates that size differences within the specimens are due to different ontogenetic stages, from juveniles to fully grown individuals. The little dinosaurs must have lived on one of the large islands around the Lower Saxony basin. Comparison with the long-bone histology of large-bodied sauropods suggests that the island dwarf species evolved through a decrease in growth rate from its larger ancestor.  相似文献   

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