|
Hongshanornis
''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 ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithuromorpha
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 the enantiornithines. This group was defined in the ''PhyloCode'' by Juan Benito and colleagues in 2022 as "the largest clade containing '' Vultur gryphus'', but not '' Enantiornis leali'' and '' Cathayornis yandica''". 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longicrusavis
''Longicrusavis'' (meaning "long shin bird" in Latin) is an extinct genus of basal ornithuromorph bird found only at Dawangzhangzi village in Liaoning Province, China. ''Longicrusavis'' was a ground dwelling carnivore, a wader, and part of biological family Hongshanornithidae, considered to have been a dominant species in the Jehol Biota, the prehistoric Chinese ecosystem which supported them. The name Hongshanornithidae refers to one of China's oldest recorded cultures in the region, the Hongshan culture. Description ''Longicrusavis'' is a ground dwelling carnivore known from the holotype specimen PKUP V1069, found from the Lower Cretaceous Yixian Formation in Liaoning Province, China., which consists of shale slab and counter slab. The skeleton is nearly complete and belongs to an adult individual, with carbonized feathers preserved in full plumage with visible colouration around the head and forelimbs. Like the closely related genus ''Hongshanornis'', ''Longicrusavis'' ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hongshanornithidae
Hongshanornithidae is an extinct group of early Ornithuromorpha, ornithuromorph birds from the early Cretaceous period of China. It includes the genus, genera ''Hongshanornis'' (the type genus) and ''Tianyuornis'' from the Yixian Formation of Inner Mongolia, ''Longicrusavis'' from the Yixian Formation of Liaoning Province, ''Parahongshanornis'' from the Jiufotang Formation of Liaoning Province, and ''Archaeornithura'', the oldest known member, from the Huajiying Formation of Hebei Province. Description Hongshanornithids were small, approximately the size of modern Phoebe (bird), phoebes. Their legs are proportionally long in comparison to the wings, suggesting that they were aquatic wading birds. They most likely lacked beaks and had teeth in their jaws. Classification Hongshanornithidae was defined as a Cladistics#Three definitions of clade, node-based clade including the last common ancestor of ''Hongshanornis longicresta'' and ''Longicrusavis houi'' plus all its descendan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pygostyle
Pygostyle is 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 control. Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parahongshanornis
''Parahongshanornis'' is an extinct genus of early bird from the lower Cretaceous (Aptian stage) of what is now Liaoning Province, north-eastern China. ''Parahongshanornis'' was first named by Li Li, Wang Jingqi and Hou Shilin in 2011 and the type species is ''Parahongshanornis chaoyangensis''. The generic name refers to an assumed close relationship with ''Hongshanornis''. The specific name refers to Chaoyang. ''Parahongshanornis'' is known from the holotype PMOL-AB00161, which was found near Yuanjiawa, Chaoyang, in the middle Aptian Jiufotang Formation of the Jehol Biota, about 120 million years old. It consists of a nearly complete and articulated skeleton missing the skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ... but showing remains of the soft parts of the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compression Fossil
A compression fossil is a fossil preserved in sedimentary rock that has undergone physical compression. While it is uncommon to find animals preserved as good compression fossils, it is very common to find plants preserved this way. The reason for this is that physical compression of the rock often leads to distortion of the fossil. The best fossils of leaves are found preserved in fine layers of sediment that have been compressed in a direction perpendicular to the plane of the deposited sediment. Since leaves are basically flat, the resulting distortion is minimal. Plant stems and other three-dimensional plant structures do not preserve as well under compression. Typically, only the basic outline and surface features are preserved in compression fossils; internal anatomy is not preserved. These fossils may be studied while still partially entombed in the sedimentary rock matrix where they are preserved, or once lifted out of the matrix by a peel or transfer technique. Compr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taphonomic
Taphonomy is the study of how organisms decay and become fossilized or preserved in the paleontological record. The term ''taphonomy'' (from Greek , 'burial' and , 'law') was introduced to paleontology in 1940 by Soviet scientist Ivan Efremov to describe the study of the transition of remains, parts, or products of organisms from the biosphere to the lithosphere. The term taphomorph is used to describe fossil structures that represent poorly-preserved, deteriorated remains of a mixture of taxonomic groups, rather than of a single one. Description Taphonomic phenomena are grouped into two phases: biostratinomy, events that occur between death of the organism and the burial; and diagenesis, events that occur after the burial. Since Efremov's definition, taphonomy has expanded to include the fossilization of organic and inorganic materials through both cultural and environmental influences. Taphonomy is now most widely defined as the study of what happens to objects after they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Reports
''Scientific Reports'' is a peer-reviewed open-access scientific mega journal published by Nature Portfolio, covering all areas of the natural sciences. The journal was established in 2011. The journal states that their aim is to assess solely the scientific validity of a submitted paper, rather than its perceived importance, significance, or impact. In September 2016, the journal became the largest in the world by number of articles, overtaking '' PLOS ONE''. Abstracting and indexing The journal is abstracted and indexed in the Chemical Abstracts Service, the Science Citation Index Expanded, and selectively in Index Medicus/MEDLINE/PubMed. According to the ''Journal Citation Reports'', the journal has a 2023 impact factor 3.8. Reviewing policy The ''Guide to Referees'' states that to be published, "a paper must be scientifically valid and technically sound in methodology and analysis", and reviewers have to ensure manuscripts "are not assessed based on their perceived impor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plowshare
In agriculture, a plowshare (Differences between American and British spellings, US) or ploughshare (Differences between American and British spellings, UK; ) is a component of a plow (or plough). It is the cutting or leading edge, preceding the moldboard, and it closely follows the coulter (Agriculture), coulter (one or more ground-breaking Nail (fastener), 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 plowshares are found at the sites of Chinese Majiabang culture dated to 3500 BC around Lake Ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 Megaannum#SI prefix multipliers, 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 Anoxic event#Cretaceous, early Aptian Oceanic Anoxic Event 1a (OAE1a) was 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 Plateau, Ontong Java-Manihiki Plateau, Manihiki-Hikurangi Plateau, Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Onto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeorhynchus
''Archaeorhynchus'' (meaning "ancient snout") is a genus of beaked avialans from the early Cretaceous period. A fossil of its only known species, ''Archaeorhynchus spathula'', was first reported in 2005 by Zhou & Zhang to have been found in Yixian Formation rocks at Yixian, Liaoning province, China, showing a well-preserved and essentially complete skeleton. Two more complete specimens were found in Lower Cretaceous deposits of Jianchang, Liaoning, northeastern China, preserving new anatomical information. These deposits are 120 million years old, whereas the original specimen was 125 million years old, meaning the age range for this species is 125-120Ma. ''Archaeorhychus'' is one of the earliest avialans known to have had a beak, and represents one of the most basal ornithuromorph avialans. The fossils preserved feathers associated with the neck, head and tail regions. The fossils also show grooves and openings/ holes (foramina) on the tips of the upper and lower jaws, suggesti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
