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Gobihadros Size
''Gobihadros'' is a genus of basal hadrosauroid dinosaur that lived in Asia during the Late Cretaceous period in what is now the Bayan Shireh Formation (Cenomanian-Santonian). It contains only the type species ''Gobihadros mongoliensis''. It has an estimated length of . Discovery and naming Between 1993 and 2004, the Mongolian Palaeontological Center and the Japanese Hayashibara Museum of Natural Sciences excavated sites at Bayshin Tsav. Material was discovered of a basal hadrosauroid new to science. Tsogtbaatar treated this species in his dissertation of 2008. In 2019, the type species ''Gobihadros mongoliensis'' was named and described by Khishigjav Tsogtbaatar, David Bruce Weishampel, David Christopher Evans, and Mahito Watabe. The generic name combines references to the Gobi Desert and the Hadrosauroidea. The specific name refers to the provenance from Mongolia. Because the describing article appeared in an electronic publication, Life Science Identifiers were needed to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenomanian
The Cenomanian is, in the ICS' geological timescale, the oldest or earliest age of the Late Cretaceous Epoch or the lowest stage of the Upper Cretaceous Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding age. Both age and stage bear the same name. As a unit of geologic time measure, the Cenomanian Age spans the time between 100.5 and 93.9 million years ago (Mya). In the geologic timescale, it is preceded by the Albian and is followed by the Turonian. The Upper Cenomanian starts around at 95 Mya. The Cenomanian is coeval with the Woodbinian of the regional timescale of the Gulf of Mexico and the early part of the Eaglefordian of the regional timescale of the East Coast of the United States. At the end of the Cenomanian, an anoxic event took place, called the Cenomanian-Turonian boundary event or the "Bonarelli event", that is associated with a minor extinction event for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claosaurus Agilis
''Claosaurus'' ( ; Greek κλάω, ''klao'' meaning 'broken' and , ''sauros'' meaning 'lizard'; "broken lizard", referring to the odd position of the fossils when discovered) is a genus of hadrosauroid dinosaur that lived during the Late Cretaceous Period (Santonian-Campanian). Traditionally classified as an early member of the family Hadrosauridae, a 2008 analysis found ''Claosaurus agilis'' to be outside of the clade containing ''Hadrosaurus'' and other hadrosaurids, making it the closest non-hadrosaurid relative of true hadrosaurids within the clade Hadrosauria. Description Because of the insufficient fossil remains ("minority of skull and partial skeleton"), the size of an adult ''Claosaurus'' remains uncertain. However, Thomas Holtz gave a length estimate of and a mass estimate as that of a lion. Like other hadrosaurs, it was an herbivore. History Evidence of its existence was first found in the Niobrara Formation near the Smoky Hill River in Kansas, United States i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eolambia
''Eolambia'' (meaning "dawn lambeosaurine") is a genus of herbivorous hadrosauroid dinosaur from the early Late Cretaceous of the United States. It contains a single species, ''E. caroljonesa'', named by paleontologist James Kirkland in 1998. The type specimen of ''Eolambia'' was discovered by Carole and Ramal Jones in 1993; the species name honors Carole. Since then, hundreds of bones have been discovered from both adults and juveniles, representing nearly every element of the skeleton. All of the specimens have thus far been found in Emery County, Utah, in a layer of rock known as the Mussentuchit Member of the Cedar Mountain Formation. Measuring up to long, ''Eolambia'' is a large member of its group. While it closely approaches the Asian hadrosauroids ''Equijubus'', ''Probactrosaurus'', and '' Choyrodon'', in traits of the skull, vertebrae, and limbs, it may actually be more closely related to the North American ''Protohadros''. This grouping, based on the straightness of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Probactrosaurus Gobiensis
''Probactrosaurus'' (meaning "before '' Bactrosaurus''") is an early herbivorous hadrosauroid iguanodont dinosaur. It lived in China during the Late Cretaceous period. Discovery and species In 1959 and 1960 a Soviet-Chinese expedition uncovered the remains of a euornithopod in Inner Mongolia near Maortu. The type species is ''Probactrosaurus gobiensis'', described and named by A. K. Rozhdestvensky in 1966. The generic name refers to Rozhdestvensky's hypothesis that ''Probactrosaurus'' would be the direct ancestor of ''Bactrosaurus'', a notion now discarded. The specific name refers to the Gobi desert. The holotype specimen, PIN 2232/1, a partial skeleton with skull, was found in layers of the Dashuigou Formation. Another partial skeleton, PIN 2232-10, was found along with numerous other fragments. In 1966 Rozhdestvensky also named a second species, ''Probactrosaurus alashanicus'', based on fragmentary material. Its specific name refers to the Alxa League. In 2002 Dav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bactrosaurus Johnsoni
''Bactrosaurus'' (; meaning "Club lizard," "baktron" = club + ''sauros'' = lizard) is a genus of herbivorous hadrosauroid dinosaur that lived in Asia during the Late Cretaceous, about 96-85 million years ago. The position ''Bactrosaurus'' occupies in the Cretaceous makes it one of the earliest known hadrosauroids, and although it is not known from a full skeleton, ''Bactrosaurus'' is one of the best known of these early hadrosauroids, making its discovery a significant finding. Discovery The first ''Bactrosaurus'' remains recovered from the Iren Dabasu Formation in the Gobi Desert of China were composed of partial skeletons of six individual ''B. johnsoni''. The specimens collected appear to come from a variety of age groups, from individuals that may be hatchlings to full-sized adults. The fossils were described in 1933 by Charles W. Gilmore, who named the new animal ''Bactrosaurus'', or "club lizard", in reference to the large club-shaped neural spines projecting from some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Evolution
Parallel evolution is the similar development of a trait in distinct species that are not closely related, but share a similar original trait in response to similar evolutionary pressure.Zhang, J. and Kumar, S. 1997Detection of convergent and parallel evolution at the amino acid sequence level. ''Mol. Biol. Evol.'' 14, 527-36. Parallel vs. convergent evolution Given a particular trait that occurs in each of two lineages descended from a specified ancestor, it is possible in theory to define parallel and convergent evolutionary trends strictly, and distinguish them clearly from one another. However the criteria for defining convergent as opposed to parallel evolution often are unclear in practice, so that arbitrary diagnosis is common in some cases. When two species are similar in a particular character, evolution is defined as parallel if the ancestors shared that similarity; if they did not, the evolution of that character in those species is defined as convergent. However, thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibia
The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects the knee with the ankle. The tibia is found on the medial side of the leg next to the fibula and closer to the median plane. The tibia is connected to the fibula by the interosseous membrane of leg, forming a type of fibrous joint called a syndesmosis with very little movement. The tibia is named for the flute '' tibia''. It is the second largest bone in the human body, after the femur. The leg bones are the strongest long bones as they support the rest of the body. Structure In human anatomy, the tibia is the second largest bone next to the femur. As in other vertebrates the tibia is one of two bones in the lower leg, the other being the fibula, and is a component of the knee and ankle joints. The ossification or formation of the bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Remodeling
Bone remodeling (or bone metabolism) is a lifelong process where mature bone tissue is removed from the skeleton (a process called '' bone resorption'') and new bone tissue is formed (a process called ''ossification'' or ''new bone formation''). These processes also control the reshaping or replacement of bone following injuries like fractures but also micro-damage, which occurs during normal activity. Remodeling responds also to functional demands of the mechanical loading. In the first year of life, almost 100% of the skeleton is replaced. In adults, remodeling proceeds at about 10% per year. An imbalance in the regulation of bone remodeling's two sub-processes, bone resorption and bone formation, results in many metabolic bone diseases, such as osteoporosis. Physiology Bone homeostasis involves multiple but coordinated cellular and molecular events. Two main types of cells are responsible for bone metabolism: osteoblasts (which secrete new bone), and osteoclasts (which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Resorption
Bone resorption is resorption of bone tissue, that is, the process by which osteoclasts break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone tissue to the blood. The osteoclasts are multi-nucleated cells that contain numerous mitochondria and lysosomes. These are the cells responsible for the resorption of bone. Osteoblasts are generally present on the outer layer of bone, just beneath the periosteum. Attachment of the osteoclast to the osteon begins the process. The osteoclast then induces an infolding of its cell membrane and secretes collagenase and other enzymes important in the resorption process. High levels of calcium, magnesium, phosphate and products of collagen will be released into the extracellular fluid as the osteoclasts tunnel into the mineralized bone. Osteoclasts are prominent in the tissue destruction found in psoriatic arthritis and rheumatological disorders. The human body is in a constant state ... [...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] |
Femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia (shinbone) and patella (kneecap), forming the knee joint. By most measures the two (left and right) femurs are the strongest bones of the body, and in humans, the largest and thickest. Structure The femur is the only bone in the upper leg. The two femurs converge medially toward the knees, where they articulate with the proximal ends of the tibiae. The angle of convergence of the femora is a major factor in determining the femoral-tibial angle. Human females have thicker pelvic bones, causing their femora to converge more than in males. In the condition ''genu valgum'' (knock knee) the femurs converge so much that the knees touch one another. The opposite extreme is ''genu varum'' (bow-leggedness). In the general pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
