Changyuraptor Temporal range: Early Cretaceous, | |
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Life restoration of C. yangi | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Family: | † Dromaeosauridae |
Clade: | † Microraptoria |
Genus: | † Changyuraptor Han et al., 2014 |
Type species | |
†Changyuraptor yangi Han et al., 2014 |
Changyuraptor is a genus of "four-winged", predatory dinosaurs. It is known from a single fossil specimen representing the species Changyuraptor yangi, which was discovered from Early Cretaceous (125 million year old) deposits in Liaoning Province, China. [1] C. yangi belongs to the group of dromaeosaurid theropod dinosaurs called the Microraptoria. [1]
At the time of its discovery, C. yangi was the largest four-winged dinosaur known [1] [2] and among the largest Mesozoic flying paravians, volant true birds seldom approaching its size. [3]
Analysis of the fossil at the University of Cape Town, South Africa reveals that the specimen was a fully grown adult, approximately 1.2 metres (3.9 ft) long and estimated to weigh 4 kilograms (8.8 lb), roughly the size of a turkey. These dimensions make Changyuraptor the largest four-winged microraptorine known, exceeding previously known specimens in size by at least 60%. [4] [5] [6]
Like other microraptorines, Changyuraptor had feathers all over its body, including forelimbs and hindlimbs, which gives the appearance of having two pairs of wings. The presence of long feathers on all four limbs also suggests that these dinosaurs could fly. [4]
The dinosaur's tail is long and feathered, with end feathers up to 29.27 centimetres (11.52 in) long, equalling approximately 30% of the length of the animal's skeleton. [1] This length exceeds the previous record length of 7 inches (18 cm) for feathers from non-avian dinosaurs. [4] The elongated tail feathers are thought to have helped provide softer and safer landings. [4] They could have controlled pitch, a feature useful for a heavier animal, that would have attained a faster gliding speed. [1]
While elongated feathers on the hindlimbs were present in many early birds, such as Archaeopteryx , the morphology of microraptorines suggests a different aerodynamic model from that of modern birds, which have characteristically bald legs and exhibit stable flight using two wings only. [6]
Changyuraptor is thought to have existed alongside a variety of predatory and herbivorous dinosaurs of the Jehol Biota, including Yutyrannus , in moist temperate forest, primarily vegetated by ginkgos and conifers, with hot, dry summers and frosty winters. [4]
The fossil, holotype HG B016, was discovered by farmers near Xijianchang in the Early Cretaceous fossil deposits, the Yixian Formation, of the Jehol Biota, located in the Liaoning province of China. From 2012 it was studied by an international team of scientists led by Dr. Luis Chiappe, Director of the Dinosaur Institute Department at the Natural History Museum of Los Angeles County. [4] [7] The holotype consists of a rather complete skeleton with skull, compressed on a plate and counterplate. It shows extensive remains of the integument in the form of pennaceous feathers. [1] In 2014, the specimen was described as the new genus and species Changyuraptor yangi. The generic name of the dinosaur combines the Chinese words for "long feather", 長羽 (cháng yǔ), with Latin raptor ("robber", "seizer"). The specific name honours researcher Professor Yang Yandong. [8]
The Jehol Biota are found in the richest fossil beds for feathered dinosaurs in the world which have yielded notable species such as Yutyrannus huali , a feathered tyrannosauroid with a length of 27 to 30 feet (8.2 to 9.1 m) and the largest feathered dinosaur known to date. [4] [9]
In 2003 Microraptor , a raven-sized dinosaur, approximately 1 kilogram (2.2 lb) in weight, was the first of the microraptorines to be discovered. It shared with species such as Anchiornis and Xiaotingia large feathered limbs and elongated bony tails with long tail feathers. These features caused experts to hypothesize that miniaturisation was an essential evolutionary step to enable flight. Changyuraptor's larger size and weight contradicts that hypothesis. [5] [6] Changyuraptor is also the second four-winged dinosaur to be discovered after Microraptor. [1] Changyuraptor and other microraptorines add to the evidence that dinosaurs had evolved a host of morphological features and behaviours such as feathers, hollow bones, nesting behaviour, and possibly flight, before they evolved in birds. [5] [6] [8]
Dromaeosauridae is a family of feathered coelurosaurian theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek δρομαῖος (dromaîos), meaning 'running at full speed', 'swift', and σαῦρος (saûros), meaning 'lizard'. In informal usage, they are often called raptors, a term popularized by the film Jurassic Park; several genera include the term "raptor" directly in their name, and popular culture has come to emphasize their bird-like appearance and speculated bird-like behavior.
Microraptor is a genus of small, four-winged dromaeosaurid dinosaurs. Numerous well-preserved fossil specimens have been recovered from Liaoning, China. They date from the early Cretaceous Jiufotang Formation, 125 to 120 million years ago. Three species have been named, though further study has suggested that all of them represent variation in a single species, which is properly called M. zhaoianus. Cryptovolans, initially described as another four-winged dinosaur, is usually considered to be a synonym of Microraptor.
Confuciusornis is a genus of basal crow-sized avialan from the Early Cretaceous Period of the Yixian and Jiufotang Formations of China, dating from 125 to 120 million years ago. Like modern birds, Confuciusornis had a toothless beak, but closer and later relatives of modern birds such as Hesperornis and Ichthyornis were toothed, indicating that the loss of teeth occurred convergently in Confuciusornis and living birds. It was thought to be the oldest known bird to have a beak, though this title now belongs to an earlier relative Eoconfuciusornis. It was named after the Chinese moral philosopher Confucius. Confuciusornis is one of the most abundant vertebrates found in the Yixian Formation, and several hundred complete specimens have been found.
Beipiaosaurus is a genus of therizinosauroid theropod dinosaurs that lived in China during the Early Cretaceous in the Yixian Formation. The first remains were found in 1996 and formally described in 1999. Before the discovery of Yutyrannus, Beipiaosaurus were among the heaviest dinosaurs known from direct evidence to be feathered. Beipiaosaurus is known from three reported specimens. Numerous impressions of feather structures were preserved that allowed researchers to determine the feathering color which turned out to be brownish.
Sinornithosaurus is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period of the Yixian Formation in what is now China. It was the fifth non–avian feathered dinosaur genus discovered by 1999. The original specimen was collected from the Sihetun locality of western Liaoning. It was found in the Jianshangou beds of the Yixian Formation, dated to 124.5 million years ago. Additional specimens have been found in the younger Dawangzhangzi bed, dating to around 122 million years ago.
Jinfengopteryx is a genus of maniraptoran dinosaur. It was found in the Qiaotou Member of the Huajiying Formation of Hebei Province, China, and is therefore of uncertain age. The Qiaotou Member may correlate with the more well-known Early Cretaceous Yixian Formation, and so probably dates to around 122 Ma ago.
Microraptoria is a clade of basal dromaeosaurid theropod dinosaurs. The first microraptorians appeared 125 million years ago in China. Many are known for long feathers on their legs and may have been semiarboreal powered fliers, some of which were even capable of launching from the ground. Most microraptorians were relatively small; adult specimens of Microraptor range between 77–90 centimetres long (2.53–2.95 ft) and weigh up to 1 kg (2.2 lb), making them some of the smallest known nonavialan dinosaurs.
Shanag is a genus of dromaeosaurid theropod dinosaur from the Early Cretaceous Period of Mongolia.
Paraves are a widespread group of theropod dinosaurs that originated in the Middle Jurassic period. In addition to the extinct dromaeosaurids, troodontids, anchiornithids, and possibly the scansoriopterygids, the group also contains the avialans, which include diverse extinct taxa as well as the over 10,000 species of living birds. Basal members of Paraves are well known for the possession of an enlarged claw on the second digit of the foot, which was held off the ground when walking in some species. A number of differing scientific interpretations of the relationships between paravian taxa exist. New fossil discoveries and analyses make the classification of Paraves an active subject of research.
Protopteryx is an extinct bird and possibly the basalmost enantiornithean, from the Cretaceous period. 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. Protopteryx has been found in the Daibeigou formation, as well. The name Protopteryx means "primitive feather": "proto-" meaning "the first of" and "-pteryx" meaning "feather" or "wing." The name comes from the fact that Protopteryx feathers are more primitive than those of modern birds, such as the two elongated tail feathers that lack barbs and rami.
Anchiornis is a genus of small, four-winged paravian dinosaurs, with only one known species, the type species Anchiornis huxleyi, named for its similarity to modern birds. The Latin name Anchiornis derives from a Greek word meaning "near bird", and huxleyi refers to Thomas Henry Huxley, a contemporary of Charles Darwin.
Hesperonychus was a small, carnivorous dinosaur. It was a member of the family Dromaeosauridae, along with its larger relatives Deinonychus and Velociraptor. There is one described species, Hesperonychus elizabethae. The type species was named in honor of Dr. Elizabeth Nicholls of the Royal Tyrrell Museum of Palaeontology who collected it as a student in 1982. It is known from fossils recovered from the lowermost strata of the Dinosaur Park Formation of Alberta, dating to the late Cretaceous about 76.5 million years ago. Though known from partial remains, researchers have estimated that it was a small dinosaur measuring about 1 metre (3.3 ft) long and weighing between 1.5 and 2 kilograms, making it the smallest carnivorous non-avian dinosaur known from North America.
Tianyuraptor is a genus of short-armed dromaeosaurid dinosaur that lived during the Early Cretaceous, about 122 million years ago. Its remains have been found in western Liaoning, China. It was similar to other dromaeosaurids found in Liaoning, with the exception of being somewhat more primitive. The type specimen, formally named in 2009, shows features not seen in previously known Northern Hemisphere (Laurasian) dromaeosaurids, but present in Southern Hemisphere (Gondwanan) species and early birds. Because of this, the scientists who first studied Tianyuraptor described it as a "transitional species", bridging the gap between northern and southern types of dromaeosaurid. Tianyuraptor also differs from previously known dromaeosaurids in that it possesses a relatively small furcula ("wishbone"), and unusually short forelimbs.
Jinfengopteryginae is a subfamily of bird-like theropod dinosaurs known from the Cretaceous of Eurasia. This group includes relatively few genera, with members discovered in 2005 but the name erected in 2012. Like other troodontids, this group of dinosaurs resided in the Paraves potentially close to the Avialae.
This timeline of dromaeosaurid research is a chronological listing of events in the history of paleontology focused on the dromaeosaurids, a group of sickle-clawed, bird-like theropod dinosaurs including animals like Velociraptor. Since the Native Americans of Montana used the sediments of the Cloverly Formation to produce pigments, they may have encountered remains of the dromaeosaurid Deinonychus hundreds of years before these fossils came to the attention of formally trained scientists.
Zhenyuanlong is a genus of dromaeosaurid dinosaur from the Yixian Formation of Liaoning, China. It lived during the Aptian age of the early Cretaceous period, approximately 125 million years ago. It is known from a single specimen belonging to the species Zhenyuanlong suni. This type specimen preserved a nearly complete skeleton that contains traces of feathers, including long tail feathers and large wings. In addition to further complicating diversity of Liaoning dromaeosaurids, this specimen provides the first direct evidence of well-developed pennaceous feathers in a large, non-flying dromaeosaur, raising the question of what function such wings would serve.
Zhongjianosaurus is a genus of dromaeosaurid belonging to the Microraptoria. Believed to hail from the Yixian Formation, specifically the middle of the Jehol Biota, it is the smallest known microraptorine thus far discovered and one of the smallest non-avian theropod dinosaurs.
Jianianhualong is a genus of troodontid theropod dinosaur from the Early Cretaceous of China. It contains a single species, Jianianhualong tengi, named in 2017 by Xu Xing and colleagues based on an articulated skeleton preserving feathers. The feathers at the middle of the tail of Jianianhualong are asymmetric, being the first record of asymmetrical feathers among the troodontids. Despite aerodynamic differences from the flight feathers of modern birds, the feathers in the tail vane of Jianianhualong could have functioned in drag reduction whilst the animal was moving. The discovery of Jianianhualong supports the notion that asymmetrical feathers appeared early in the evolutionary history of the Paraves.
Wulong is a genus of microraptorine dromaeosaurid dinosaurs from the Early Cretaceous (Aptian) Jiufotang Formation of China. The genus includes a single species, Wulong bohaiensis. The skeletal remains, which include preserved feathers, represent a juvenile.