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Physiology Of Dinosaurs
The physiology of dinosaurs has historically been a controversial subject, particularly their thermoregulation. Recently, many new lines of evidence have been brought to bear on dinosaur physiology generally, including not only metabolic systems and thermoregulation, but on respiratory and cardiovascular systems as well. During the early years of dinosaur paleontology, it was widely considered that they were sluggish, cumbersome, and sprawling cold-blooded lizards. However, with the discovery of much more complete skeletons in western United States, starting in the 1870s, scientists could make more informed interpretations of dinosaur biology and physiology. Edward Drinker Cope, opponent of Othniel Charles Marsh in the Bone Wars, propounded at least some dinosaurs as active and agile, as seen in the painting of two fighting '' Laelaps'' produced under his direction by Charles R. Knight. In parallel, the development of Darwinian evolution, and the discoveries of '' Archaeoptery ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoregulation
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature as its own body temperature, thus avoiding the need for internal thermoregulation. The internal thermoregulation process is one aspect of homeostasis: a state of dynamic stability in an organism's internal conditions, maintained far from thermal equilibrium with its environment (the study of such processes in zoology has been called physiological ecology). If the body is unable to maintain a normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs. Humans may also experience lethal hyperthermia when the wet bulb temperature is sustained above for six hours. The opposite condition, when body temperature decreases below normal levels, is known as hypothermia. It results when the homeostatic c ... [...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] |
John Ostrom
John Harold Ostrom (February 18, 1928 – July 16, 2005) was an American paleontologist who revolutionized modern understanding of dinosaurs in the 1960s. As first proposed by Thomas Henry Huxley in the 1860s, Ostrom showed that dinosaurs were more like big non-flying birds than they were like lizards (or "saurians"), and even proved that birds themselves are a type of theropod saurischian dinosaur. Since dinosaurs themselves are considered reptiles, Ostrom's work made zoologists question whether birds should be considered an order of Reptilia instead of their own class, Aves. The first of Ostrom's broad-based reviews of the osteology and phylogeny of the primitive bird '' Archaeopteryx'' appeared in 1976. His reaction to the eventual discovery of feathered dinosaurs in China, after years of acrimonious debate, was bittersweet. Early life and career Ostrom was born in New York in 1928 and grew up in Schenectady. As a pre-medical undergraduate student at Union College, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory System
The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plants. The anatomy and physiology that make this happen varies greatly, depending on the size of the organism, the environment in which it lives and its evolutionary history. In land animals the respiratory surface is internalized as linings of the lungs. Gas exchange in the lungs occurs in millions of small air sacs; in mammals and reptiles these are called alveoli, and in birds they are known as atria. These microscopic air sacs have a very rich blood supply, thus bringing the air into close contact with the blood. These air sacs communicate with the external environment via a system of airways, or hollow tubes, of which the largest is the trachea, which branches in the middle of the chest into the two main bronchi. These enter the lungs where they branch into progressively narrower secondary and tert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs. In humans, the heart is approximately the size of a closed fist and is located between the lungs, in the middle compartment of the chest. In humans, other mammals, and birds, the heart is divided into four chambers: upper left and right atria and lower left and right ventricles. Commonly the right atrium and ventricle are referred together as the right heart and their left counterparts as the left heart. Fish, in contrast, have two chambers, an atrium and a ventricle, while most reptiles have three chambers. In a healthy heart blood flows one way through the heart due to heart valves, which prevent backflow. The heart is enclosed in a protective sac, the pericardium, which also contains a small amount of fluid. The wall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Palace Dinosaurs
The Crystal Palace Dinosaurs are a series of sculptures of dinosaurs and other extinct animals, incorrect by modern standards, in the London borough of Bromley's Crystal Palace Park. Commissioned in 1852 to accompany the Crystal Palace after its move from the Great Exhibition in Hyde Park, they were unveiled in 1854 as the first dinosaur sculptures in the world. The models were designed and sculpted by Benjamin Waterhouse Hawkins under the scientific direction of Sir Richard Owen, representing the latest scientific knowledge at the time. The models, also known as Dinosaur Court, were classed as Grade II listed buildings from 1973, extensively restored in 2002, and upgraded to Grade I listed in 2007. The models represent 15 genera of extinct animals, only three of which are true dinosaurs. They are from a wide range of geological ages, and include true dinosaurs, ichthyosaurs, and plesiosaurs mainly from the Mesozoic era, and some mammals from the more recent Cenozoic era. Today ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadruped
Quadrupedalism is a form of locomotion where four limbs are used to bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four limbs is said to be a quadruped (from Latin ''quattuor'' for "four", and ''pes'', ''pedis'' for "foot"). Quadruped animals are found among both vertebrates and invertebrates. Quadrupeds vs. tetrapods Although the words ‘quadruped’ and ‘tetrapod’ are both derived from terms meaning ‘four-footed’, they have distinct meanings. A tetrapod is any member of the taxonomic unit Tetrapoda (which is defined by descent from a specific four-limbed ancestor), whereas a quadruped actually uses four limbs for locomotion. Not all tetrapods are quadrupeds and not all entities that could be described as ‘quadrupedal’ are tetrapods. This last meaning includes certain artificial objects; almost all quadruped ''organisms'' are tetrapods (with the exception of some raptorial arthropods adapted fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Owen
Sir Richard Owen (20 July 1804 – 18 December 1892) was an English biologist, comparative anatomist and paleontologist. Owen is generally considered to have been an outstanding naturalist with a remarkable gift for interpreting fossils. Owen produced a vast array of scientific work, but is probably best remembered today for coining the word '' Dinosauria'' (meaning "Terrible Reptile" or "Fearfully Great Reptile"). An outspoken critic of Charles Darwin's theory of evolution by natural selection, Owen agreed with Darwin that evolution occurred, but thought it was more complex than outlined in Darwin's ''On the Origin of Species''. Owen's approach to evolution can be considered to have anticipated the issues that have gained greater attention with the recent emergence of evolutionary developmental biology. Owen was the first president of the Microscopical Society of London in 1839 and edited many issues of its journal – then known as ''The Microscopic Journal''. Owen also c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gideon Mantell
Gideon Algernon Mantell MRCS FRS (3 February 1790 – 10 November 1852) was a British obstetrician, geologist and palaeontologist. His attempts to reconstruct the structure and life of ''Iguanodon'' began the scientific study of dinosaurs: in 1822 he was responsible for the discovery (and the eventual identification) of the first fossil teeth, and later much of the skeleton, of ''Iguanodon''. Mantell's work on the Cretaceous of southern England was also important. Early life and medical career Mantell was born in Lewes, Sussex as the fifth-born child of Thomas Mantell, a shoemaker, and Sarah Austen. He was raised in a small cottage in St. Mary's Lane with his two sisters and four brothers. As a youth, he showed a particular interest in the field of geology. He explored pits and quarries in the surrounding areas, discovering ammonites, shells of sea urchins, fish bones, coral, and worn-out remains of dead animals. The Mantell children could not study at local grammar schools ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Buckland
William Buckland Doctor of Divinity, DD, Royal Society, FRS (12 March 1784 – 14 August 1856) was an English theologian who became Dean of Westminster. He was also a geologist and paleontology, palaeontologist. Buckland wrote the first full account of a fossil dinosaur, which he named ''Megalosaurus''. His work proved that Kirkdale Cave in North Yorkshire had been a prehistoric hyena den, for which he was awarded the Copley Medal. It was praised as an example of how scientific analysis could reconstruct distant events. He pioneered the use of fossilised Feces, faeces in reconstructing ecosystems, coining the term coprolites. Buckland followed the Gap creationism, Gap Theory in interpreting the biblical account of ''Genesis'' as two widely separated episodes of creation. It had emerged as a way to reconcile the scriptural account with discoveries in geology suggesting the earth was very old. Early in his career Buckland believed he had found evidence of the Deluge myth, biblic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
London - Crystal Palace - Victorian Dinosaurs 1
London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a major settlement for two millennia. The City of London, its ancient core and financial centre, was founded by the Romans as ''Londinium'' and retains its medieval boundaries.See also: Independent city § National capitals The City of Westminster, to the west of the City of London, has for centuries hosted the national government and parliament. Since the 19th century, the name "London" has also referred to the metropolis around this core, historically split between the counties of Middlesex, Essex, Surrey, Kent, and Hertfordshire, which largely comprises Greater London, governed by the Greater London Authority.The Greater London Authority consists of the Mayor of London and the London Assembly. The London Mayor is distinguished fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
