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Zhongyuansaurus
''Zhongyuansaurus'' (meaning “Zhongyuan lizard”) is a monospecific genus of ankylosaurid dinosaur from Henan that lived during the Early Cretaceous (Aptian-Albian, ~125.0-100.5 Ma) in what is now the Haoling Formation. ''Zhongyuansaurus '' is possibly a junior synonym of '' Gobisaurus'', a basal ankylosaurid from the Ulansuhai Formation of Inner Mongolia. Discovery and naming The type species, ''Zhongyuansaurus luoyangensis'', was named and described in 2007 by Xu and colleagues. The holotype specimen of ''Zhongyuansaurus'', HGM 41HIII-0002, consists of a nearly complete skull, fragments of the lower jaw, a cervical neural spine, dorsal vertebrae, caudal vertebrae, posterior caudal centra, fused distal caudals, ribs, a humerus, both ischia, a pubis, and osteoderms. The specimen was obtained from the Haoling Formation of the Henan Province, Ruyang County. The specimen is currently housed at the Henan Province Geological Museum in China. The generic name, ''Zhongyuansaurus' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ankylosauridae
Ankylosauridae () is a family of armored dinosaurs within Ankylosauria, and is the sister group to Nodosauridae. The oldest known Ankylosaurids date to around 122 million years ago and went extinct 66 million years ago during the Cretaceous–Paleogene extinction event. These animals were mainly herbivorous and were obligate quadrupeds, with leaf-shaped teeth and robust, scute-covered bodies. Ankylosaurids possess a distinctly domed and short snout, wedge-shaped osteoderms on their skull, scutes along their torso, and a tail club. Ankylosauridae is exclusively known from the northern hemisphere, with specimens found in western North America, Europe, and East Asia. The first discoveries within this family were of the genus '' Ankylosaurus'', by Peter Kaiser and Barnum Brown in Montana in 1906. Brown went on to name Ankylosauridae and the subfamily Ankylosaurinae in 1908. Anatomy Ankylosaurids are stout, solidly built, armoured dinosaurs. They possess accessory ossifications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gobisaurus
''Gobisaurus'' is an extinct genus of herbivorous basal ankylosaurid ankylosaur from the Upper Cretaceous (and possibly also the Lower Cretaceous) of China ('' Nei Mongol Zizhiqu''). The genus is monotypic, containing only the species ''Gobisaurus domoculus''. Discovery and naming The Sino-Soviet Expeditions (1959–1960) discovered an ankylosaurian skeleton in the Gobi Desert of Inner Mongolia near Moartu, in the region of the Alashan Desert. The find was largely neglected until fossils were selected for a travelling exhibition touring the globe between 1990 and 1997, in the context of the China-Canada Dinosaur Project. The postcranial skeleton could not be located but the skull was displayed, informally labelled "Gobisaurus", at the time a ''nomen nudum''. In 2001, Matthew K. Vickaryous, Anthony P. Russell, Philip John Currie and Zhao Xijin named and described the type species ''Gobisaurus domoculus''. The generic name means "Gobi (Desert) lizard," referring to its prov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2007 In Paleontology
Plants *A fossilized rainforest is discovered in a coal mine. Angiosperms Fungi newly named Arthropoda New taxa Fish Bony fish * * * Cartilaginous fish * Archosauromorphs Pseudosuchians Pterosaurs Newly named non-dinosaurian dinosauromorphs Newly named non-avian dinosauromorphs Data courtesy of George Olshevky's dinosaur genera list. Newly named birds Lepidosauromorpha Plesiosaurs * * Synapsids Non-mammalian Mammals Footnotes Complete author list As science becomes more collaborative, papers with large numbers of authors are becoming more common. To prevent the deformation of the tables, these footnotes list the contributors to papers that erect new genera and have many authors. References {{Portal, Paleontology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ankylosaurinae
Ankylosaurinae is a subfamily of ankylosaurid dinosaurs, existing from the Early Cretaceous about 105 million years ago until the end of the Late Cretaceous, about 66 mya. Many genera are included in the clade, such as '' Ankylosaurus'', '' Pinacosaurus'', '' Euoplocephalus'', and '' Saichania''. Features Ankylosaurines are defined as being closer relatives to '' Ankylosaurus'' than to '' Shamosaurus''. Diagnostic features of ankylosaurines include the nuchal shelf that obscures the occiput in dorsal view, and the quadrate condyle which is obscured lightly by the quadratojugal boss. Phylogeny The following cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ... is based on the 50% majority rule phylogenetic analysis of Arbour & Currie (2015): References An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haoling Formation
The Haoling Formation is a Mesozoic geologic formation in the Ruyang Basin of Henan, Province, central China. Dinosaur remains are among the fossils that have been recovered from the formation. The Haoling Formation was originally treated as part of the Mangchuan Formation and considered to be of Paleocene age before being recognized as Mesozoic in age. A 2012 paper divided the Mangchuan into the Xiahedong, Haoling, and Shangdonggou Formations, assigning the dinosaur-bearing horizon to the Haoling Formation and constraining the age of the Haoling as Aptian-Albian based on fieldwork and invertebrate and microfossil assemblages. Paleofauna * '' Luoyanggia liudianensis'' * '' Xianshanosaurus shijiagouensis'' * '' Yunmenglong ruyangensis'' * '' Zhongyuanosaurus luoyangensis'' * '' Ruyangosaurus giganteus'' * ''Huanghetitan ruyangensis'' *Ornithomimidae spp. *Iguanodontia indet. *Carcharodontosauridae indet. See also * List of dinosaur-bearing rock formations ** List of stratigraphic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity due to shared ancestry between a pair of structures or genes in different taxa. A common example of homologous structures is the forelimbs of vertebrates, where the wings of bats and birds, the arms of primates, the front flippers of whales and the forelegs of four-legged vertebrates like dogs and crocodiles are all derived from the same ancestral tetrapod structure. Evolutionary biology explains homologous structures adapted to different purposes as the result of descent with modification from a common ancestor. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this, from Aristotle onwards, and it was explicitly analysed by Pierre Belon in 1555. In developmental biology, organs that developed in the embryo in the same manner and from similar origins, such as from matc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intraspecific Competition
Intraspecific competition is an interaction in population ecology, whereby members of the same species compete for limited resources. This leads to a reduction in fitness for both individuals, but the more fit individual survives and is able to reproduce. By contrast, interspecific competition occurs when members of different species compete for a shared resource. Members of the same species have rather similar requirements for resources, whereas different species have a smaller contested resource overlap, resulting in intraspecific competition generally being a stronger force than interspecific competition. Individuals can compete for food, water, space, light, mates, or any other resource which is required for survival or reproduction. The resource must be limited for competition to occur; if every member of the species can obtain a sufficient amount of every resource then individuals do not compete and the population grows exponentially. Prolonged exponential growth is rare ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interspecific Competition
Interspecific competition, in ecology, is a form of competition in which individuals of ''different'' species compete for the same resources in an ecosystem (e.g. food or living space). This can be contrasted with mutualism, a type of symbiosis. Competition between members of the same species is called intraspecific competition. If a tree species in a dense forest grows taller than surrounding tree species, it is able to absorb more of the incoming sunlight. However, less sunlight is then available for the trees that are shaded by the taller tree, thus interspecific competition. Leopards and lions can also be in interspecific competition, since both species feed on the same prey, and can be negatively impacted by the presence of the other because they will have less food. Competition is only one of many interacting biotic and abiotic factors that affect community structure. Moreover, competition is not always a straightforward, direct, interaction. Interspecific competition may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral ... [...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 Kergue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ontogeny
Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the study of the entirety of an organism's lifespan. Ontogeny is the developmental history of an organism within its own lifetime, as distinct from phylogeny, which refers to the evolutionary history of a species. Another way to think of ontogeny is that it is the process of an organism going through all of the developmental stages over its lifetime. The developmental history includes all the developmental events that occur during the existence of an organism, beginning with the changes in the egg at the time of fertilization and events from the time of birth or hatching and afterward (i.e., growth, remolding of body shape, development of secondary sexual characteristics, etc.). While developmental (i.e., ontogenetic) processes can influence sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
