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Sulcavis
''Sulcavis'' is a genus of enantiornithean birds. One species is named, ''Sulcavis geeorum''. The fossil was found in Early Cretaceous (121-125 million years ago) rocks in Liaoning Province, China. ''Sulcavis'' is the first discovery of a bird with ornamented tooth enamel. The enantiornitheans are unique among birds in showing minimal tooth reduction and a diversity of dental patterns. ''Sulcavis'' had robust teeth with grooves on the inside surface, which likely strengthened the teeth against harder food items. No previous bird species have preserved ridges, striations, serrated edges, or any other form of dental ornamentation. Discovery The holotype of ''Sulcavis'', BMNH Ph-000805, is discovered near the town of Lamadong, in Liaoning Province, China. The fossil was found in the Yixian Formation, an Early Cretaceous rock formation. The genus was described on January 9, 2013, in an article that was published in the ''Journal of Vertebrate Paleontology'' by Jingmai Kathleen O'C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiornithes
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over eighty species of Enantiornithes have been named, but some names represent only single bones, so it is likely that not all are valid. The Enantiornithes became extinct at the Cretaceous–Paleogene boundary, along with Hesperornithes and all other non-avian dinosaurs. Discovery and naming The first Enantiornithes to be discovered were incorrectly referred to modern bird groups. For example, the first known species of Enantiornithes, ''Gobipteryx minuta'', was originally considered a paleognath related to ostriches and tinamou. The Enantiornithes were first recognized as a distinct lineage, or "subclass" of birds, by Cyril A. Walker in 1981. Walker mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiornithean
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over eighty species of Enantiornithes have been named, but some names represent only single bones, so it is likely that not all are valid. The Enantiornithes became extinct at the Cretaceous–Paleogene boundary, along with Hesperornithes and all other non-avian dinosaurs. Discovery and naming The first Enantiornithes to be discovered were incorrectly referred to modern bird groups. For example, the first known species of Enantiornithes, '' Gobipteryx minuta'', was originally considered a paleognath related to ostriches and tinamou. The Enantiornithes were first recognized as a distinct lineage, or "subclass" of birds, by Cyril A. Walker in 1981. Walker mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian-Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining early Aptian Oceanic Anoxic Event 1a (OAE1a) was carbon isotope dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java-Manihiki-Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Ontong Java Plateau today covers an area of 1,860,000 km2. In the Indian Ocean another LIP began to form at c. 120 Ma, the Kerguelen P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liu Di
Liu Di (Traditional Chinese: 劉荻; Simplified Chinese: 刘荻; Pinyin: Liú Dí; born October 9, 1981), writing under the screen name " Stainless Steel Rat" (不锈钢老鼠), named after the assertive Harry Harrison science fiction character, became a symbol for democracy and free speech in China since her detention in November 2002. Her screen-name is often translated as Stainless Steel Mouse. Biography Liu Di graduated as a psychology major from Beijing Normal University. Liu's case comes during a crackdown on Internet content as the government struggles to gain control over a new and popular medium. The reasons for Liu's detention were satirizing the CCP online and calling for the release of other "cyber-dissidents." She was freed from Beijing's Qincheng prison on Friday, November 28, 2003. Two other "cyber-dissidents", Wu Yiran, and Li Yibin, were also freed from a jail for political detainees. References See also *List of Chinese dissidents *International Freedom of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longipteryx Chaoyangensis
''Longipteryx'' is a genus of prehistoric bird which lived during the Early Cretaceous (Aptian stage, 120.3 million years ago). It contains a single species, ''Longipteryx chaoyangensis''. Its remains have been recovered from the Jiufotang Formation at Chaoyang in Liaoning Province, China. Apart from the holotype IVPP V 12325 - a fine and nearly complete skeleton — another entire skeleton (IPPV V 12552) and some isolated bones (a humerus and furcula, specimens IPPV V 12553, and an ulna, IPPV V 12554) are known to date. The name ''Longipteryx'' means "one with long feathers", from Latin ''longus'', "long" + Ancient Greek ''pteryx'' (πτέρυξ), "wing", "feather" or "pinion". The specific name ''chaoyangensis'' is from the Latin for "from Chaoyang". Description Excluding the tail, ''Longipteryx'' was some 15 cm long overall in life. It had a long bill — longer than the rest of the head — with a few hooked teeth at the tip, and, as the name implies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boluochia Zhengi
''Boluochia zhengi'' was an enantiornithine bird. It lived during the Early Cretaceous in the time span 121.6-110.6 mya ( late Aptian- early Albian) and is known from fossils found in the Jiufotang Formation of Liaoning province, People's Republic of China. ''Boluochia'' was first described by Zhou in 1995.Zhou, 1995. "Discovery of a New Enantiornithine Bird from the Cretaceous of Liaoning, China". PalAsiatica 33(2):99-113 A re-analysis of the specimen by Jingmai O'Connor and colleagues found that it was closely related to ''Longipteryx ''Longipteryx'' is a genus of prehistoric bird which lived during the Early Cretaceous ( Aptian stage, 120.3 million years ago). It contains a single species, ''Longipteryx chaoyangensis''. Its remains have been recovered from the Jiufotang Form ...'' and could be assigned to the family Longipterygidae.O'Connor, J.K., Zhou Z. and Zhang F. (In press). "A reappraisal of ''Boluochia zhengi'' (Aves: Enantiornithes) and a discussion of intraclade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longipterygidae
Longipterygidae is a family of early enantiornithean avialans from the Early Cretaceous epoch of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125-120 million years ago. Description Longipterygids are characterized by an extremely long, toothed snout (making up over 60% of the total skull length), in which the teeth are restricted to the tips of the jaws. The snouts were straight but slightly concave at a point behind the nostrils, and the bones of the snout tip were solid. Their pygostyles, the series of fused vertebrae in the tail, were unusually large, and longer than the foot bones. The feet of longipterygids were also specialized relative to other enantiornitheans. Where most enantiornitheans had a long middle toe with a "knuckle" (trochlea) that extended beyond the outer two, the toes of longipterygids were even in length, and attached to the rest of the foot at the same level. This configuration is also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsornis Keni
''Elsornis'' is a genus of enantiornithine bird. Only one species is known, ''Elsornis keni''. It lived during the Late Cretaceous. It is known from a partially articulated fossil skeleton found in the Gobi Desert in Mongolia. The holotype fossil is given catalog number MPD - b 100/201. It is in the collection of the Mongolian Palaeontological Center. The fossil was collected at Togrogiin Shiree, South Gobi Aimak, Mongolia; Djadokhta Formation, Late Cretaceous, Campanian. The fossil is extremely well preserved in three dimensions. It preserves a pneumatized Furcula The (Latin for "little fork") or wishbone is a forked bone found in most birds and some species of non-avian dinosaurs, and is formed by the fusion of the two pink clavicles. In birds, its primary function is in the strengthening of the thoracic ..., which was a character previously unknown in enantiornithines. Chiappe et al. (2007) conclude from the proportions of ''Elsornis'' ' pectoral skeleton that it was fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protopteryx Fengningensis
''Protopteryx'' is an extinct bird and the most basal enantiornithean, from the Cretaceous period.Zhou, Zhonghe. (2002). "A new and primitive enantiornithine bird from the Early Cretaceous of China." ''Journal of Vertebrate Paleontology'', 22(1): 49-57. The type species is ''P. fengningensis''. It was first discovered in the Sichakou Member of the Yixian Formation or Huajiying Formation of Hebei Province, northern China, dating from 131 Ma ago.O'Connor, J.K., Zhou Z. and Zhang F. (In press). "A reappraisal of ''Boluochia zhengi'' (Aves: Enantiornithes) and a discussion of intraclade diversity in the Jehol avifauna, China." ''Journal of Systematic Palaeontology'', (published online before print 16 December 2010). ''Protopteryx ''has been found in the Daibeigou formation, as well.Zhiheng Li, Zhonghe Zhou, Min Wang, Julia A. Clarke, (2014). "A New Specimen of Large-Bodied Basal Enantiornithine ''Bohaiornis'' from the Early Cretaceous of China and the Inference of Feeding Ecology in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euornithes
Euornithes (from Greek ' meaning "true birds") is a natural group which includes the most recent common ancestor of all avialans closer to modern birds than to ''Sinornis''. Description Clarke ''et al''. (2006) found that the most primitive known euornithians (the Yanornithiformes) had a mosaic of advanced and primitive features. These species retained primitive features like gastralia and a pubic symphysis. They also showed the first fully modern pygostyles, and the type specimen of ''Yixianornis'' (IVPP 13631) preserves eight elongated rectrices (tail feathers) in a modern arrangement. No earlier pygostylians are known which preserve a fan of tail feathers of this sort; instead, they showed only paired plumes or a tuft of short feathers. Classification The name Euornithes has been used for a wide variety of avialan groups since it was first named by Edward Drinker Cope in 1889. It was first defined as a clade in 1998 by Paul Sereno, who made it the group of all animals closer t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithothoraces
Ornithothoraces is a group of avialans that includes all enantiornithes ("opposite birds") and the euornithes ("true birds"), which includes modern birds and their closest ancestors. The name Ornithothoraces means "bird thoraxes". This refers to the modern, highly advanced anatomy of the thorax that gave the ornithothoracines superior flight capability compared with more primitive avialans. This anatomy includes a large, keeled breastbone, elongated coracoids and a modified glenoid joint in the shoulder, and a semi-rigid rib cage. In spite of this at least the sternum seems to have developed convergently rather than being a true homology. The earliest known members of the group are the enantiornitheans ''Protopteryx fengningensis'', '' Eopengornis martini'', and '' Cruralispennia multidonta'', as well as the euornithine '' Archaeornithura meemannae'', all from the Sichakou Member of the Huajiying Formation in China, which has been dated to 130.7 million years old. At least one ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omnivoropterygiformes
Omnivoropterygidae (meaning "omnivorous wings") is a family of primitive avialans known exclusively from the Jiufotang Formation of China, though putative omnivoropterygids are known from the Maevarano Formation of the Maastrichtian of Madagascar. They had short skeletal tails and unusual skulls with teeth in the upper, but not lower, jaws. Their unique dentition has led some scientists to suggest an omnivorous diet for them.Czerkas, S. A. & Ji, Q. (2002). "A preliminary report on an omnivorous volant bird from northeast China." ''In'': Czerkas, S. J. (editor): ''Feathered Dinosaurs and the origin of flight. The Dinosaur Museum Journal'' 1: 127-135HTML abstract/ref> The family was named by Stephen A. Czerkas & Qiang Ji Qiang Ji from the Rensselaer Polytechnic Institute, Troy, New York, United States, was named Fellow of the Institute of Electrical and Electronics Engineers The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) profession ... in 2002, tho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
