|
Hongshanornis Wingspan
''Hongshanornis'' is a genus of ornithuromorph birds known from early Cretaceous lake deposits of the Yixian Formation, Inner Mongolia, China. The holotype specimen, recovered in 2005, is currently held by the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. It was found in the Jianshangou fossil beds, dated to 124.6 million years ago. Three additional specimens have been reported, though only one of those has been definitively identified as belonging to ''Hongshanornis''. This latter specimen was found in the Dawangzhangzi fossil beds, which are about 122 million years old. ''Hongshanornis'' is a member of the group Hongshanornithidae, to which it lent its name. It is closely related to ''Longicrusavis'', which existed alongside ''Hongshanornis'' in the Dawangzhangzi ecosystem, and is very similar to the later ''Parahongshanornis'' from the Jiufotang Formation. Description ''Hongshanornis longicresta'' was a small species, especially compared to other early ... [...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] |
Ornithischia
Ornithischia () is an extinct order of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name ''Ornithischia'', or "bird-hipped", reflects this similarity and is derived from the Greek stem ' (), meaning "of a bird", and ' (), plural ', meaning "hip joint". However, birds are only distantly related to this group as birds are theropod dinosaurs. Ornithischians with well known anatomical adaptations include the ceratopsians or "horn-faced" dinosaurs (e.g. ''Triceratops''), the pachycephalosaurs or "thick-headed" dinosaurs, the armored dinosaurs (Thyreophora) such as stegosaurs and ankylosaurs, and the ornithopods. There is strong evidence that certain groups of ornithischians lived in herds, often segregated by age group, with juveniles forming their own flocks separate from adults. Some were at least partially covered in filamentous (hair- or feather- like) pelts, and there is much debate over whether these filaments fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hongshanornis Wingspan
''Hongshanornis'' is a genus of ornithuromorph birds known from early Cretaceous lake deposits of the Yixian Formation, Inner Mongolia, China. The holotype specimen, recovered in 2005, is currently held by the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. It was found in the Jianshangou fossil beds, dated to 124.6 million years ago. Three additional specimens have been reported, though only one of those has been definitively identified as belonging to ''Hongshanornis''. This latter specimen was found in the Dawangzhangzi fossil beds, which are about 122 million years old. ''Hongshanornis'' is a member of the group Hongshanornithidae, to which it lent its name. It is closely related to ''Longicrusavis'', which existed alongside ''Hongshanornis'' in the Dawangzhangzi ecosystem, and is very similar to the later ''Parahongshanornis'' from the Jiufotang Formation. Description ''Hongshanornis longicresta'' was a small species, especially compared to other early ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eogranivora
''Eogranivora'' is a bird genus, belonging to the Ornithuromorpha, that lived in the area of present-day China during the Early Cretaceous. Its type species is ''Eogranivora edentulata''.Zheng X., O’Connor J.K., Wang X., Wang Y., Zhou Z. 2018. "Reinterpretation of a previously described Jehol bird clarifies early trophic evolution in the Ornithuromorpha". ''Proceedings of the Royal Society B'' 285: 20172494 In 2011, a bird fossil, specimen STM35-3 found at Dawangzhangzi, was referred to '' Hongshanornis''.Zheng X-T., Martin L.D., Zhou Z-H., Burnham D.A., Zhang F-C., Miao D. 2011 "Fossil evidence of avian crops from the Early Cretaceous of China". ''Proceedings of the National Academy of Sciences. USA'' 108: 15 904–15 907 Subsequently, that genus was proven to possess teeth, while STM35-3 is toothless. Additional research showed that the latter represented a species new to science. In 2018, the type species ''Eogranivora edentulata'' was named and described by Zheng Xiaotin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crop (anatomy)
A crop (sometimes also called a croup or a craw, ingluvies, or sublingual pouch) is a thin-walled expanded portion of the alimentary tract used for the storage of food prior to digestion. This anatomical structure is found in a wide variety of animals. It has been found in birds, and in invertebrate animals including gastropods (snails and slugs), earthworms, leeches, and insects. Insects Cropping is used by bees to temporarily store nectar of flowers. When bees "suck" nectar, it is stored in their crops. Other Hymenoptera also use crops to store liquid food. The crop in eusocial insects, such as ants, has specialized to be distensible, and this specialization enables important communication between colonial insects through trophallaxis. The crop can be found in the foregut of insects. Birds In a bird's digestive system, the crop is an expanded, muscular pouch near the gullet or throat. It is a part of the digestive tract, essentially an enlarged part of the esophagus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrolith
A gastrolith, also called a stomach stone or gizzard stone, is a rock held inside a gastrointestinal tract. Gastroliths in some species are retained in the muscular gizzard and used to grind food in animals lacking suitable grinding teeth. In other species the rocks are ingested and pass through the digestive system and are frequently replaced. The grain size depends upon the size of the animal and the gastrolith's role in digestion. Other species use gastroliths as ballast.Rondeau, et aLarval Anurans Adjust Buoyancy in Response to Substrate IngestionCopeia: February 2005, Vol. 2005, No. 1, pp. 188-195. Particles ranging in size from sand to cobble have been documented. Etymology Gastrolith comes from the Greek γαστήρ (''gastēr''), meaning "stomach", and λίθος (''lithos''), meaning "stone". Occurrence Among living vertebrates, gastroliths are common among crocodiles, alligators, herbivorous birds, seals and sea lions. Domestic fowl require access to ''grit''. Stone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunbittern
The sunbittern (''Eurypyga helias'') is a bittern-like bird of tropical regions of the Americas, and the sole member of the family Eurypygidae (sometimes spelled Eurypigidae) and genus ''Eurypyga''. It is found in Central and South America, and has three subspecies. The sunbittern shows both morphological and molecular similarities with the kagu (''Rhynochetos jubatus'') of New Caledonia, indicating a gondwanic origin, both species being placed in the clade Eurypygiformes.del Hoyo, J. Elliott, A. & Sargatal, J. (editors). (1996) ''Handbook of the Birds of the World. Volume 3: Hoatzin to Auks''. Lynx Edicions. Taxonomy The sunbittern is usually placed in the Gruiformes, but this was always considered preliminary. Altogether, the bird is most similar to another bird that was provisionally placed in the Gruiformes, the kagu (''Rhynochetos jubatus''). Molecular studies seem to confirm that the kagu and sunbittern are each other's closest living relatives and have a similar wing d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrant Flycatcher
The tyrant flycatchers (Tyrannidae) are a family of passerine birds which occur throughout North and South America. They are considered the largest family of birds known to exist in the world, with more than 400 species. They are the most diverse avian family in every country in the Americas, except for the United States and Canada. The members vary greatly in shape, patterns, size and colors. Some tyrant flycatchers may superficially resemble the Old World flycatchers, which they are named after but are not closely related to. They are members of suborder Tyranni (suboscines), which do not have the sophisticated vocal capabilities of most other songbirds.del Hoyo, J. Elliott, A. & Christie, D. (editors). (2004) ''Handbook of the Birds of the World. Volume 9: Cotingas to Pipits and Wagtails''. Lynx Edicions. A number of species previously included in this family are now placed in the family Tityridae (''see Systematics''). Sibley and Alquist in their 1990 bird taxonomy had the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accipiter
''Accipiter'' is a genus of Bird of prey, birds of prey in the family Accipitridae. With 51 recognized species it is the most diverse genus in its family. Most species are called goshawks or sparrowhawks, although almost all New World species (excepting the northern goshawk) are simply known as hawks. They can be anatomically distinguished from their relatives by the lack of a coracoid, procoracoid foramen. Two small and aberrant species usually placed here do possess a large procoracoid foramen and are also distinct as regards DNA sequence. They may warrant separation in the old genus ''Hieraspiza''.Olson (2006) Extant accipiters range in size from the little sparrowhawk (''A. minullus''), in which the smallest males measure long, span across the wings and weigh , to the northern goshawk (''A. gentilis''), in which the largest females measure long, span across the wings, and weigh . These birds are slender with short, broad, rounded wings and a long tail which helps them mane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pygostyle
Pygostyle describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main component of the uropygium, a structure colloquially known as the bishop's nose, parson's nose, pope's nose, or sultan's nose. This is the fleshy protuberance visible at the posterior end of a bird (most commonly a chicken or turkey) that has been dressed for cooking. It has a swollen appearance because it also contains the uropygial gland that produces preen oil. Evolution Pygostyles probably began to evolve very early in the Cretaceous period, perhaps 140 – 130 million years ago. The earliest known species to have evolved a pygostyle were members of the Confuciusornithidae. The structure provided an evolutionary advantage, as a completely mobile tail as found in species such as '' Archaeopteryx'' is detrimental to its use for flight contro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plowshare
In agriculture, a plowshare ( US) or ploughshare ( UK; ) is a component of a plow (or plough). It is the cutting or leading edge of a moldboard which closely follows the coulter (one or more ground-breaking spikes) when plowing. The plowshare itself is often a hardened blade dressed into an integral moldboard (by the blacksmith) so making a unified combination of plowshare and moldboard, the whole being responsible for entering the cleft in the earth (made by the coulter's first cutting-through) and turning the earth over. In well-tilled terrain the plowshare may do duty without a preceding coulter. In modern plows both coulter and plowshare are detachable for easy replacement when worn or broken. History Triangular-shaped stone ploughshares are found at the sites of Chinese Majiabang culture dated to 3500 BC around Lake Tai. Ploughshares have also been discovered at the nearby Liangzhu and Maqiao sites roughly dated to the same period. The British archaeologist David R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_01.JPG "Click for more on -> Tyrant Flycatcher")
.jpg "Click for more on -> Plowshare")