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 T. Late Cretaceous (100mya - 65mya refers to the second half of the Cretaceous Period, named after the famous white Chalk cliffs of southern England rex skull, Palais de la Découverte, Paris.
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Tyrannosaurus (pronounced /tɨˌrænəˈsɔːrəs/ or /taɪˌrænoʊˈsɔːrəs/, meaning 'tyrant lizard') is a genus of theropod dinosaur. In biology a type is that which fixes a name to a Taxon. Depending on the nomenclature code which is applied to the organism in question a type may be a specimen In Scientific nomenclature, synonyms are different Scientific names used for a single Taxon. Edward Drinker Cope (July 28 1840&ndashApril 12 1897 was an American paleontologist and comparative anatomist, as well as a noted herpetologist Henry Fairfield Osborn ( August 8, 1857 – November 6, 1935) was an American Geologist, Paleontologist, and Nanotyrannus ("tiny tyrant" is a genus of Tyrannosaurid Dinosaur, and is possibly a juvenile specimen of Tyrannosaurus Robert T Bakker (born March 24, 1945, in Bergen County New Jersey) is an American Paleontologist who helped reshape modern theories about George Olshevsky (born 1946 is a freelance editor, Writer, Publisher, Paleontologist, and Mathematician living in San Diego George Olshevsky (born 1946 is a freelance editor, Writer, Publisher, Paleontologist, and Mathematician living in San Diego A genus (plural genera from Γένος Latin genus "descent family type gender" is a low-level Taxonomic Theropods (ˈθɪərəpɒd theropoda /θiːˈrɒpədə/ 'beast feet' are a group of Bipedal Saurischian Dinosaurs Although they were primarily The famous species Tyrannosaurus rex ('rex' meaning 'king' in Latin), commonly abbreviated to T. In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. rex, is a fixture in popular culture around the world. Popular culture (or pop culture) is the Culture — patterns of human activity and the symbolic structures that give such activities significance and importance — It lived throughout what is now western North America, with a much wider range than other tyrannosaurids. Fossils of T. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. rex are found in a variety of rock formations dating to the last three million years of the Cretaceous Period, approximately 68 to 65 million years ago; it was among the last non-avian dinosaurs to exist prior to the Cretaceous–Tertiary extinction event. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of In Astronomy, Geology, and Paleontology, mya or " mya " is an abbreviation for "million years ago". The Cretaceous–Tertiary extinction event, which occurred approximately ( Ma) was a large-scale mass extinction of animal and plant species in a geologically
Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Bipedalism is a form of Terrestrial locomotion where an organism moves by means of its two rear limbs A carnivore (ˈkɑrnɪvɔər meaning 'meat eater' ( Latin carne meaning 'flesh' and vorare meaning 'to devour' is any animal with a diet consisting Relative to the large and powerful hindlimbs, Tyrannosaurus forelimbs were small, though unusually powerful for their size, and bore two primary digits, along with a possible third vestigial digit. Vestigiality describes homologous characters of Organisms which have lost all or most of their original function in a species through Although other theropods rivaled or exceeded T. rex in size, it was the largest known tyrannosaurid and one of the largest known land predators, measuring up to 13 meters (43 ft) in length,[1] up to 4 meters (13 ft) tall at the hips,[2] and up to 6. Size has been one of the most interesting aspects of Dinosaur science to the general public The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International A foot (plural feet or foot; symbol or abbreviation ft or sometimes &prime – the prime symbol) is a non-SI unit 8 metric tons (7. This article is about the tonne or metric ton For other tons see Ton. 5 short tons) in weight. The short ton ( S/T) is a unit of mass equal to 2000 lb (around 907 [3] By far the largest carnivore in its environment, T. rex may have been an apex predator, preying upon hadrosaurs and ceratopsians, although some experts have suggested it was primarily a scavenger. Hadrosaurids or duck-billed Dinosaurs are members of the family Hadrosauridae, and include Ornithopods such as Edmontosaurus Ceratopsia or Ceratopia (ˌsɛrəˈtɒpsiə/ /ˌsɛrəˈtoʊpiə Greek: "horned faces" is a group of herbivorous, beaked Dinosaurs Scavenging, or necrophagy, is a Carnivorous Feeding behaviour in which a predator consumes Corpses or Carrion that were killed
More than 30 specimens of T. rex have been identified, some of which are nearly complete skeletons. Soft tissue and proteins have been reported in at least one of these specimens. In Medicine, the term soft tissue refers to tissues that connect support or surround other structures and organs of the body Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl The abundance of fossil material has allowed significant research into many aspects of its biology, including life history and biomechanics. Foundations of modern biology There are five unifying principles Biomechanics is the application of mechanical principles on living organisms The feeding habits, physiology and potential speed of T. Physiology (from Greek grc φύσις physis, "nature origin" and grc -λογία -logia) is the study of the mechanical physical rex are a few subjects of debate. Its taxonomy is also controversial, with some scientists considering Tarbosaurus bataar from Asia to represent a second species of Tyrannosaurus and others maintaining Tarbosaurus as a separate genus. Taxonomy is the practice and science of classification The word comes from the Greek, taxis (meaning 'order' 'arrangement' and, nomos Tarbosaurus (; meaning "terrifying lizard" is a Genus of Tyrannosaurid Theropod Dinosaur that flourished in Several other genera of North American tyrannosaurids have also been synonymized with Tyrannosaurus. In Scientific nomenclature, synonyms are different Scientific names used for a single Taxon.
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Description
Tyrannosaurus rex was one of the largest land carnivores of all time; the largest complete specimen, FMNH PR2081 ("Sue"), measured 12. The Field Museum of Natural History is located in Chicago, Illinois, USA. "Sue" is the nickname given to FMNH PR2081, which is the largest most extensive and best preserved Tyrannosaurus rex specimen ever 8 meters (42 feet) long, and was 4. The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International A foot (plural feet or foot; symbol or abbreviation ft or sometimes &prime – the prime symbol) is a non-SI unit 0 meters (13 ft) tall at the hips. [2] Mass estimates have varied widely over the years, from more than 7. 2 metric tons (8 short tons),[4] to less than 4. 5 metric tons (5 tons),[5][6] with most modern estimates ranging between 5. 4 and 6. 8 metric tons (between 6 and 7. 5 tons). [7][8][9][3] Although Tyrannosaurus rex was larger than the well known Jurassic theropod Allosaurus, it was slightly smaller than Cretaceous carnivores Spinosaurus and Giganotosaurus. The Jurassic is a geologic period and system that extends from about Ma (million years ago to Ma that is from the end of the Triassic to the beginning Allosaurus (ˌæləˈsɔrəs is a Genus of large Theropod Dinosaur that lived 155 to 145 million years ago in the Late Jurassic Spinosaurus (meaning "spine lizard" is a Genus of theropod Dinosaur which lived in what is now North Africa, from Giganotosaurus (meaning 'giant southern lizard' derived from the Ancient Greek gigas/γίγας meaning 'giant' notos/νότος [10][11]
The neck of T. rex formed a natural S-shaped curve like that of other theropods, but was short and muscular to support the massive head. The forelimbs were long thought to bear only two digits, but there is an unpublished report of a third, vestigial digit in one specimen. [12] In contrast the hind limbs were among the longest in proportion to body size of any theropod. The tail was heavy and long, sometimes containing over forty vertebrae, in order to balance the massive head and torso. A vertebra (plural vertebrae) is an individual Irregular bone in the spinal or Vertebral column ( aka ischis a flexuous and flexible column To compensate for the immense bulk of the animal, many bones throughout the skeleton were hollow, reducing its weight without significant loss of strength. [1]
The largest known T. rex skulls measure up to 1. 5 meters (5 ft) in length. Large fenestrae (openings) in the skull reduced weight and provided areas for muscle attachment, as in all carnivorous theropods. But in other respects Tyrannosaurus’ skull was significantly different from those of large non-tyrannosauroid theropods. Tyrannosauroidea (meaning 'tyrant lizard forms' is a Superfamily (or Clade) of Coelurosaurian Theropod Dinosaurs that includes It was extremely wide at the rear but had a narrow snout, allowing unusually good binocular vision. Binocular vision is vision in which both Eyes are used together [13] The skull bones were massive and the nasals and some other bones were fused, preventing movement between them; but many were pneumatized (contained a "honeycomb" of tiny air spaces) which may have made the bones more flexible as well as lighter. The nasal bones are two small oblong Bones varying in size and form in different individuals they are placed side by side at the middle and upper part of the Face These and other skull-strengthening features are part of the tyrannosaurid trend towards an increasingly powerful bite, which easily surpassed that of all non-tyrannosaurids. Tyrannosauridae (or tyrannosaurids, meaning "tyrant lizards" is a family of Coelurosaurian Theropod Dinosaurs which [14] [15][16] The tip of the upper jaw was U-shaped (most non-tyrannosauroid carnivores had V-shaped upper jaws), which increased the amount of tissue and bone a tyrannosaur could rip out with one bite, although it also increased the stresses on the front teeth. [17][18]
The teeth of T. rex displayed marked heterodonty (differences in shape). The anatomical term heterodont (from Greek, meaning 'different teeth' refers to Animals which possess more than a single tooth morphology. [19][1] The premaxillary teeth at the front of the upper jaw were closely-packed, D-shaped in cross-section, had reinforcing ridges on the rear surface, were incisiform (their tips were chisel-like blades) and curved backwards. The premaxilla is a pair of small Cranial bones at the very tip of the jaws of many animals usually bearing Teeth, but not always Incisors (from Latin incidere, "to cut" are the first kind of Tooth in Heterodont Mammals They are located in the Premaxilla The D-shaped cross-section, reinforcing ridges and backwards curve reduced the risk that the teeth would snap when Tyrannosaurus bit and pulled. The remaining teeth were robust, like "lethal bananas" rather than daggers, more widely spaced and also had reinforcing ridges. [20] Those in the upper jaw were larger than those in all but the rear of the lower jaw. The largest found so far is estimated to have been 30 centimeters (12 in) long including the root when the animal was alive, making it the largest tooth of any carnivorous dinosaur. [21]
Classification
Tyrannosaurus is the type genus of the superfamily Tyrannosauroidea, the family Tyrannosauridae, and the subfamily Tyrannosaurinae; in other words it is the standard by which paleontologists decide whether to include other species in the same group. In biology a type is that which fixes a name to a Taxon. Depending on the nomenclature code which is applied to the organism in question a type may be a specimen Tyrannosauroidea (meaning 'tyrant lizard forms' is a Superfamily (or Clade) of Coelurosaurian Theropod Dinosaurs that includes In Biological classification, family ( Latin Tyrannosauridae (or tyrannosaurids, meaning "tyrant lizards" is a family of Coelurosaurian Theropod Dinosaurs which Other members of the tyrannosaurine subfamily include the North American Daspletosaurus and the Asian Tarbosaurus,[22][23] both of which have occasionally been synonymized with Tyrannosaurus. Daspletosaurus (; meaning 'frightful lizard' is a Genus of Tyrannosaurid Theropod Dinosaur that lived in western North America [18] Tyrannosaurids were once commonly thought to be descendants of earlier large theropods such as megalosaurs and carnosaurs, although more recently they were reclassified with the generally smaller coelurosaurs. Spinosauroidea is a superfamily of tetanuran theropod Dinosaurs that lived from the Middle Jurassic to the Late Cretaceous period Carnosauria is a group of large Predatory Dinosaurs that lived during the Jurassic and Cretaceous periods For the prehistoric gliding reptile see Coelurosauravus. Coelurosauria (sɨˌljʊərəˈsɔriə is defined as the clade containing all Theropod [17]
In 1955, Soviet paleontologist Evgeny Maleev named a new species, Tyrannosaurus bataar, from Mongolia. The Union of Soviet Socialist Republics (USSR was a constitutionally Socialist state that existed in Eurasia from 1922 to 1991 Palaeontology redirects here For the Scientific journal, see Palaeontology (journal. Evgeny Aleksandrovich Maleev (Евгений Александрович Малеев 1915-1966 (pronounced 'Malay-ef' was a Russian Paleontologist who named the Mongolia (mɒŋˈɡoʊliə, literally Mongol country/nation,) is a Landlocked Country in East [24] By 1965, this species had been renamed Tarbosaurus bataar. [25] Despite the renaming, many phylogenetic analyses have found Tarbosaurus bataar to be the sister taxon of Tyrannosaurus rex,[23] and it has often been considered an Asian species of Tyrannosaurus. Cladistics is the hierarchical classification of Species based on evolutionary ancestry [17][26][27] A recent redescription of the skull of Tarbosaurus bataar has shown that it was much narrower than that of Tyrannosaurus rex and that during a bite, the distribution of stress in the skull would have been very different, closer to that of Alioramus, another Asian tyrannosaur. Alioramus (ˌæliːoʊˈreɪməs meaning 'different branch' is a Genus of Tyrannosaurid Theropod Dinosaur from the Late Cretaceous [28] A related cladistic analysis found that Alioramus, not Tyrannosaurus, was the sister taxon of Tarbosaurus, which, if true, would suggest that Tarbosaurus and Tyrannosaurus should remain separate. Cladistics is the hierarchical classification of Species based on evolutionary ancestry [22]
Other tyrannosaurid fossils found in the same formations as T. rex were originally classified as separate taxa, including Aublysodon and Albertosaurus megagracilis,[18] the latter being named Dinotyrannus megagracilis in 1995. [29] However, these fossils are now universally considered to belong to juvenile T. rex. [30] A small but nearly complete skull from Montana, 60 cm (2 ft) long, may be an exception. This skull was originally classified as a species of Gorgosaurus (G. Gorgosaurus (, meaning "fierce lizard" is a Genus of Tyrannosaurid Theropod Dinosaur that lived in western North lancensis) by Charles W. Gilmore in 1946,[31] but was later referred to a new genus, Nanotyrannus. Charles Whitney Gilmore (1874-1945 was an American paleontologist, who named Dinosaurs in North America and Mongolia, including the Nanotyrannus ("tiny tyrant" is a genus of Tyrannosaurid Dinosaur, and is possibly a juvenile specimen of Tyrannosaurus [32] Opinions remain divided on the validity of N. lancensis. Many paleontologists consider the skull to belong to a juvenile T. rex. [33] There are minor differences between the two species, including the higher number of teeth in N. lancensis, which lead some scientists to recommend keeping the two genera separate until further research or discoveries clarify the situation. [23][34]
Manospondylus
The first fossil specimen which can be attributed to Tyrannosaurus rex consists of two partial vertebrae (one of which has been lost) found by Edward Drinker Cope in 1892 and described as Manospondylus gigas. Edward Drinker Cope (July 28 1840&ndashApril 12 1897 was an American paleontologist and comparative anatomist, as well as a noted herpetologist Osborn recognized the similarity between M. gigas and T. rex as early as 1917 but, due to the fragmentary nature of the Manospondylus vertebrae, he could not synonymize them conclusively. [35]
In June 2000, the Black Hills Institute located the type locality of M. The Black Hills Institute of Geological Research Inc (BHI is a private Corporation specializing in the excavation and preparation of Fossils as well as the sale gigas in South Dakota and unearthed more tyrannosaur bones there. These were judged to represent further remains of the same individual, and to be identical to those of T. rex. According to the rules of the International Code of Zoological Nomenclature (ICZN), the system that governs the scientific naming of animals, Manospondylus gigas should therefore have priority over Tyrannosaurus rex, because it was named first. The International Code of Zoological Nomenclature is a set of rules in Zoology that have one fundamental aim to provide the maximum universality and continuity in the naming [36] However, the Fourth Edition of the ICZN, which took effect on January 1, 2000, states that "the prevailing usage must be maintained" when "the senior synonym or homonym has not been used as a valid name after 1899" and "the junior synonym or homonym has been used for a particular taxon, as its presumed valid name, in at least 25 works, published by at least 10 authors in the immediately preceding 50 years…"[37] Tyrannosaurus rex easily qualifies as the valid name under these conditions and would most likely be considered a nomen protectum ("protected name") under the ICZN if it was ever challenged, which it has not yet been. New Year See also New Year The Ancient Romans began their consular year on January 1st since 153 BC 2000 ( MM) was a Leap year that started on Saturday of the Common Era, in accordance with the Gregorian calendar. A conserved name or nomen conservandum (plural nomina conservanda) is a scientific name that enjoys special nomenclatural protection Manospondylus gigas would then be deemed a nomen oblitum ("forgotten name"). A nomen oblitum ( Latin for "forgotten name" is a name that has not been used in the scientific community for more than fifty years after its original proposal [38]
Paleobiology
Life history
The identification of several specimens as juvenile Tyrannosaurus rex has allowed scientists to document ontogenetic changes in the species, estimate the lifespan, and determine how quickly the animals would have grown. Ontogeny, as opposed to Phylogeny, refers to the history of an organism from birth as opposed to its genetic makeup The smallest known individual (LACM 28471, the "Jordan theropod") is estimated to have weighed only 29. The Natural History Museum of Los Angeles County opened in Exposition Park, Los Angeles, California, USA in 1913 as the Museum of History Science 9 kg (66 lb), while the largest, such as FMNH PR2081 ("Sue") most likely weighed over 5400 kg (6 short tons). The Field Museum of Natural History is located in Chicago, Illinois, USA. "Sue" is the nickname given to FMNH PR2081, which is the largest most extensive and best preserved Tyrannosaurus rex specimen ever The short ton ( S/T) is a unit of mass equal to 2000 lb (around 907 Histologic analysis of T. Histology (from the Greek = 'tissue' is the study of the microscopic anatomy of cells and tissues of Plants and rex bones showed LACM 28471 had aged only 2 years when it died, while "Sue" was 28 years old, an age which may have been close to the maximum for the species. [3]
Histology has also allowed the age of other specimens to be determined. Growth curves can be developed when the ages of different specimens are plotted on a graph along with their mass. A T. rex growth curve is S-shaped, with juveniles remaining under 1800 kg (2 short tons) until approximately 14 years of age, when body size began to increase dramatically. During this rapid growth phase, a young T. rex would gain an average of 600 kg (1,300 lb) a year for the next four years. At 18 years of age, the curve plateaus again, indicating that growth slowed dramatically. For example, only 600 kg (1,300 lb) separated the 28-year-old "Sue" from a 22-year-old Canadian specimen (RTMP 81. Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page The Royal Tyrrell Museum of Palaeontology (commonly known as the Royal Tyrrell Museum) is a popular Canadian tourist attraction and a leading center of palaeontological 12. 1). [3] Another recent histological study performed by different workers corroborates these results, finding that rapid growth began to slow at around 16 years of age. [39] This sudden change in growth rate may indicate physical maturity, a hypothesis which is supported by the discovery of medullary tissue in the femur of a 16 to 20-year-old T. The femur is the thigh bone In Humans, it is the longest, most voluminous and strongest Bone. rex from Montana (MOR 1125, also known as "B-rex"). The Museum of the Rockies, affiliated with Montana State University in Bozeman and the Smithsonian Institution, is located in Bozeman, Montana Medullary tissue is found only in female birds during ovulation, indicating that "B-rex" was of reproductive age. [40] Further study indicates an age of 18 for this specimen. [41] Other tyrannosaurids exhibit extremely similar growth curves, although with lower growth rates corresponding to their lower adult sizes. [42]
Over half of the known T. rex specimens appear to have died within six years of reaching sexual maturity, a pattern which is also seen in other tyrannosaurs and in some large, long-lived birds and mammals today. These species are characterized by high infant mortality rates, followed by relatively low mortality among juveniles. Mortality increases again following sexual maturity, partly due to the stresses of reproduction. One study suggests that the rarity of juvenile T. rex fossils is due in part to low juvenile mortality rates; the animals were not dying in large numbers at these ages, and so were not often fossilized. However, this rarity may also be due to the incompleteness of the fossil record or to the bias of fossil collectors towards larger, more spectacular specimens. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. [42]
Sexual dimorphism
As the number of specimens increased, scientists began to analyze the variation between individuals and discovered what appeared to be two distinct body types, or morphs, similarly to some other theropod species. As one of these morphs was more solidly built, it was termed the 'robust' morph while the other was termed 'gracile. ' Several morphological differences associated with the two morphs were used to analyze sexual dimorphism in Tyrannosaurus rex, with the 'robust' morph usually suggested to be female. The term morphology in Biology refers to the outward appearance ( Shape, Structure, Colour, Pattern) of an Organism Sexual dimorphism is the systematic difference in form between individuals of different Sex in the same Species. For example, the pelvis of several 'robust' specimens seemed to be wider, perhaps to allow the passage of eggs. The pelvis (pl pelvises or pelves) or pelvic girdle is the irregular bony structure located at the base of the spine (properly known In most Birds and Reptiles an egg ( Latin ovum) is the Zygote, resulting from Fertilization of the Ovum. [43] It was also thought that the 'robust' morphology correlated with a reduced chevron on the first tail vertebra, also ostensibly to allow eggs to pass out of the reproductive tract, as had been erroneously reported for crocodiles. A chevron is one of a series of Bones on the ventral (under side of the tail in many Reptiles Dinosaurs (such as Diplodocus The reproductive system is a system of organs within an Organism which work together for the purpose of Reproduction. A crocodile is any Species belonging to the family Crocodylidae (sometimes classified instead as the Subfamily Crocodylinae) [44]
In recent years, evidence for sexual dimorphism has been weakened. A 2005 study reported that previous claims of sexual dimorphism in crocodile chevron anatomy were in error, casting doubt on the existence of similar dimorphism between T. rex genders. [45] A full-sized chevron was discovered on the first tail vertebra of "Sue," an extremely robust individual, indicating that this feature could not be used to differentiate the two morphs anyway. As T. rex specimens have been found from Saskatchewan to New Mexico, differences between individuals may be indicative of geographic variation rather than sexual dimorphism. Saskatchewan (səˈskætʃəwən) is a prairie province in Canada, which has an area of 588276 New Mexico ( is a state located in the southwestern region of the United States of America. The differences could also be age-related, with 'robust' individuals being older animals. [1]
Only a single T. rex specimen has been conclusively shown to belong to a specific gender. Examination of "B-rex" demonstrated the preservation of soft tissue within several bones. Some of this tissue has been identified as medullary tissue, a specialized tissue grown only in modern birds as a source of calcium for the production of eggshell during ovulation. As only female birds lay eggs, medullary tissue is only found naturally in females, although males are capable of producing it when injected with female reproductive hormones like estrogen. Hormones (from Greek ὁρμή - "impetus" are chemicals released by cells that affect cells in other parts of the body Estrogens (US otherwise oestrogens or œstrogens) are a group of Steroid compounds named for their importance in the Estrous cycle, This strongly suggests that "B-rex" was female, and that she died during ovulation. [40] Recent research has shown that medullary tissue is never found in crocodiles, which are thought to be the closest living relatives of dinosaurs, aside from birds. The shared presence of medullary tissue in birds and theropod dinosaurs is further evidence of the close evolutionary relationship between the two. eVolution is the third Album by eLDee, it was due to be released in 2008 [46]
Posture
Like many bipedal dinosaurs, Tyrannosaurus rex was historically depicted as a 'living tripod', with the body at 45 degrees or less from the vertical and the tail dragging along the ground, similar to a kangaroo. A kangaroo is a Marsupial from the family Macropodidae (macropods meaning 'large foot' This concept dates from Joseph Leidy's 1865 reconstruction of Hadrosaurus, the first to depict a dinosaur in a bipedal posture. Joseph Leidy ( September 9 1823 &ndash 30 April 1891) was an American Paleontologist. Hadrosaurus (ˌhædroʊˈsɔrəs from Greek: ἁδρος hadros + σαυρος sauros = sturdy lizard) is a dubious [47] Henry Fairfield Osborn, former president of the American Museum of Natural History (AMNH) in New York City, who believed the creature stood upright, further reinforced the notion after unveiling the first complete T. Henry Fairfield Osborn ( August 8, 1857 – November 6, 1935) was an American Geologist, Paleontologist, and The American Museum of Natural History ( AMNH) located on the Upper West Side, Manhattan, New York, USA is one of the largest and most The City of New York rex skeleton in 1915. It stood in this upright pose for nearly a century, until it was dismantled in 1992. [48] By 1970, scientists realized this pose was incorrect and could not have been maintained by a living animal, as it would have resulted in the dislocation or weakening of several joints, including the hips and the articulation between the head and the spinal column. Joint dislocation (Latin luxatio) occurs when bones in a Joint become displaced or misaligned A joint is the location at which two or more Bones make contact A vertebra (plural vertebrae) is an individual Irregular bone in the spinal or Vertebral column ( aka ischis a flexuous and flexible column [49] Despite its inaccuracies, the AMNH mount inspired similar depictions in many films and paintings (such as Rudolph Zallinger's famous mural The Age Of Reptiles in Yale University's Peabody Museum of Natural History) until the 1990s, when films such as Jurassic Park introduced a more accurate posture to the general public. Rudolph Franz Zallinger (born November 12, 1919 - August 1, 1995) was an American-based artist notable for his mural The Age of Reptiles The Peabody Museum of Natural History at Yale University is among the oldest largest and most prolific university natural history museums in the world Jurassic Park is a 1993 Science fiction film directed by Steven Spielberg and based on the novel of the same name by Michael Modern representations in museums, art, and film show T. rex with its body approximately parallel to the ground and tail extended behind the body to balance the head. [18]
Arms
.jpg/180px-Tyrannosaurus_(arm).jpg)
When Tyrannosaurus rex was first discovered, the humerus was the only element of the forelimb known. The humerus is a Long bone in the Arm or Forelimb that runs from the Shoulder to the Elbow. [50] For the initial mounted skeleton as seen by the public in 1915, Osborn substituted longer, three-fingered forelimbs like those of Allosaurus. Allosaurus (ˌæləˈsɔrəs is a Genus of large Theropod Dinosaur that lived 155 to 145 million years ago in the Late Jurassic [35] However, a year earlier, Lawrence Lambe described the short, two-fingered forelimbs of the closely-related Gorgosaurus. Lawrence Morris Lambe (1849&ndash1934 was a geologist and palaeontologist from the Geological Survey of Canada (GSC Gorgosaurus (, meaning "fierce lizard" is a Genus of Tyrannosaurid Theropod Dinosaur that lived in western North [51] This strongly suggested that T. rex had similar forelimbs, but this hypothesis was not confirmed until the first complete T. A hypothesis (from Greek) consists either of a suggested explanation for a phenomenon (an event that is observable or of a reasoned proposal suggesting a possible rex forelimbs were identified in 1989, belonging to MOR 555 (the "Wankel rex"). [52] The remains of "Sue" also include complete forelimbs. [1] T. rex 'arms' are very small relative to overall body size, measuring only one meter (3 ft) long. However, they are not vestigial but instead show large areas for muscle attachment, indicating considerable strength. Vestigiality describes homologous characters of Organisms which have lost all or most of their original function in a species through Muscle (from Latin musculus, diminutive of mus "mouse" is contractile tissue of the body and is derived from the This was recognized as early as 1906 by Osborn, who speculated that the forelimbs may have been used to grasp a mate during copulation. Sexual intercourse, in its biological sense is the act in which the male reproductive organ (in humans and other higher animals enters the female reproductive tract [53] It has also been suggested that the forelimbs were used to assist the animal in rising from a prone position. [49] Another possibility is that the forelimbs held struggling prey while it was dispatched by the tyrannosaur's enormous jaws. This hypothesis may be supported by biomechanical analysis. Biomechanics is the application of mechanical principles on living organisms T. rex forelimb bones exhibit extremely thick cortical bone, indicating that they were developed to withstand heavy loads. Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce The biceps brachii muscle of a full-grown Tyrannosaurus rex was capable of lifting 199 kg (438 lb) by itself; this number would only increase with other muscles (like the brachialis) acting in concert with the biceps. In Human anatomy, the biceps brachii is a Muscle located on the upper Arm. The brachialis ( brachialis anticus) is a Muscle in the upper Arm that flexes the elbow joint. A T. rex forearm also had a reduced range of motion, with the shoulder and elbow joints allowing only 40 and 45 degrees of motion, respectively. In contrast, the same two joints in Deinonychus allow up to 88 and 130 degrees of motion, respectively, while a human arm can rotate 360 degrees at the shoulder and move through 165 degrees at the elbow. Deinonychus (daɪˈnɒnikəs ( Greek δεινος, 'terrible' and ονυξ/ονυχος, 'claw' was a Genus of carnivorous The heavy build of the arm bones, extreme strength of the muscles, and limited range of motion may indicate a system designed to hold fast despite the stresses of a struggling prey animal. [54]
Soft tissue
In the March 2005 issue of Science, Mary Higby Schweitzer of North Carolina State University and colleagues announced the recovery of soft tissue from the marrow cavity of a fossilized leg bone, from a 68-million-year-old Tyrannosaurus. Science is the Academic journal of the American Association for the Advancement of Science and is considered one of the world's most prestigious Scientific North Carolina State University at Raleigh is a public, Coeducational extensive Research University located in Raleigh North Carolina The bone had been intentionally, though reluctantly, broken for shipping and then not preserved in the normal manner, specifically because Schweitzer was hoping to test it for soft tissue. [55] Designated as the Museum of the Rockies specimen 1125, or MOR 1125, the dinosaur was previously excavated from the Hell Creek Formation. The Hell Creek Formation is an intensely-studied division of Upper Cretaceous to lower Paleocene rocks in North America named for exposures studied along Hell Flexible, bifurcating blood vessels and fibrous but elastic bone matrix tissue were recognized. The blood vessels are part of the Circulatory system and function to transport Blood throughout the body Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce In addition, microstructures resembling blood cells were found inside the matrix and vessels. A blood cell (also called blood corpuscle) is any cell of any type normally found in Blood. The structures bear resemblance to ostrich blood cells and vessels. The Ostrich ( Struthio camelus) is a large Flightless bird native to Africa (and formerly the Middle East) Whether an unknown process, distinct from normal fossilization, preserved the material, or the material is original, the researchers do not know, and they are careful not to make any claims about preservation. [56] If it is found to be original material, any surviving proteins may be used as a means of indirectly guessing some of the DNA content of the dinosaurs involved, because each protein is typically created by a specific gene. The absence of previous finds may merely be the result of people assuming preserved tissue was impossible, therefore simply not looking. Since the first, two more tyrannosaurs and a hadrosaur have also been found to have such tissue-like structures. [57] Research on some of the tissues involved have suggested that birds are closer relatives to tyrannosaurs than other modern animals. [58]
In studies reported in the journal Science in April 2007, Asara and colleagues concluded that seven traces of collagen proteins detected in purified T. Collagen is the main Protein of Connective tissue in Animals and the most abundant protein in Mammals making up about 50% of the whole-body protein rex bone most closely match those reported in chickens, followed by frogs and newts. The chicken ( Gallus gallus, sometimes G gallus domesticus) is a domesticated Fowl which is traditionally believed to have descended from The discovery of proteins from a creature tens of millions of years old, along with similar traces the team found in a mastodon bone at least 160,000 years old, upends the conventional view of fossils and may shift paleontologists' focus from bone hunting to biochemistry. Until these finds, most scientists presumed that fossilization replaced all living tissue with inert minerals. Paleontologist Hans Larsson of McGill University in Montreal, who was not part of the studies, called the finds "a milestone", and suggested that dinosaurs could "enter the field of molecular biology and really slingshot paleontology into the modern world. "[59]
Subsequent studies in April 2008 confirmed the close connection of T. rex to modern birds. Postdoctoral biology researcher Chris Organ at Harvard University announced, "With more data, they would probably be able to place T. rex on the evolutionary tree between alligators and chickens and ostriches. for differences between alligators and crocodiles please see Crocodilia An Alligator is a Crocodilian in the Genus The Ostrich ( Struthio camelus) is a large Flightless bird native to Africa (and formerly the Middle East) " Co-author John M. Asara added, "We also show that it groups better with birds than modern reptiles, such as alligators and green anole lizards. "[60]
Skin
In 2004, the scientific journal Nature published a report describing an early tyrannosauroid, Dilong paradoxus, from the famous Yixian Formation of China. Nature is a prominent Scientific journal, first published on 4 November 1869 Dilong (which means 'emperor dragon' is a Genus of small tyrannosauroid Dinosaur. The Yixian Formation is a Geological formation in Jinzhou, Liaoning, People's Republic of China, that stems from the Early Cretaceous China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National As with many other theropods discovered in the Yixian, the fossil skeleton was preserved with a coat of filamentous structures which are commonly recognized as the precursors of feathers. Feathers are one of the epidermal growths that form the distinctive outer covering or Plumage, on Birds They are considered the most complex integumentary structures It has also been proposed that Tyrannosaurus and other closely-related tyrannosaurids had such protofeathers. However, rare skin impressions from adult tyrannosaurids in Canada and Mongolia show pebbly scales typical of other dinosaurs. [61] While it is possible that protofeathers existed on parts of the body which have not been preserved, a lack of insulatory body covering is consistent with modern multi-ton mammals such as elephants, hippopotamus, and most species of rhinoceros. The term thermal insulation can refer to materials used to reduce the rate of Heat transfer, or the methods and processes used to reduce heat transfer Elephants ( family: Elephantidae) are large land Mammals of the order Proboscidea. The hippopotamus ( Hippopotamus amphibius) from the Greek ἱπποπόταμος ( hippopotamos, ιππος hippos meaning "horse" Rhinoceros (raɪˈnɒsərəs often colloquially abbreviated rhino, is a name used to group five extant species of Odd-toed ungulates in the family As an object increases in size, its ability to retain heat increases due to its decreasing surface area-to-volume ratio. Surface area is the measure of how much exposed Area an object has The volume of any solid plasma vacuum or theoretical object is how much three- Dimensional space it occupies often quantified numerically Therefore, as large animals evolve in or disperse into warm climates, a coat of fur or feathers loses its selective advantage for thermal insulation and can instead become a disadvantage, as the insulation traps excess heat inside the body, possibly overheating the animal. eVolution is the third Album by eLDee, it was due to be released in 2008 Biological dispersal refers to those processes by which a Species maintains ecosystem Natural selection is the process by which favorable Heritable traits become more common in successive Generations of a Population of Protofeathers may also have been secondarily lost during the evolution of large tyrannosaurids like Tyrannosaurus, especially in warm Cretaceous climates. [62]
Thermoregulation
Tyrannosaurus, like most dinosaurs, was long thought to have an ectothermic ("cold-blooded") reptilian metabolism. Note In this article "dinosaur" means "non-avian dinosaur" since most experts regard birds as an advanced group of dinosaurs Cold-blooded organisms (called poikilotherms - "of varying temperature" maintain their body temperatures in ways different from Mammals and Birds Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. The idea of dinosaur ectothermy was challenged by scientists like Robert Bakker and John Ostrom in the early years of the "Dinosaur Renaissance", beginning in the late 1960s. Robert T Bakker (born March 24, 1945, in Bergen County New Jersey) is an American Paleontologist who helped reshape modern theories about John H Ostrom ( February 18, 1928 &ndash July 16, 2005) was an American Paleontologist who revolutionized modern The " Dinosaur renaissance " was a small-scale scientific revolution started in the late 1960s which led to renewed academic and popular interest in Dinosaurs [63][64] Tyrannosaurus rex itself was claimed to have been endothermic ("warm-blooded"), implying a very active lifestyle. In Biology, a warm-blooded Animal species is one whose members maintain thermal Homeostasis; that is they keep their body temperature at a roughly constant [6] Since then, several paleontologists have sought to determine the ability of Tyrannosaurus to regulate its body temperature. Thermoregulation is the ability of an Organism to keep its body temperature within certain boundaries even when temperature surrounding is very different Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Histological evidence of high growth rates in young T. rex, comparable to those of mammals and birds, may support the hypothesis of a high metabolism. Growth curves indicate that, as in mammals and birds, T. rex growth was limited mostly to immature animals, rather than the indeterminate growth seen in most other vertebrates. In Biology and especially Botany, indeterminate growth refers to growth that is not terminated in contrast to determinate growth that stops once a Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes [39]
Oxygen isotope ratios in fossilized bone are sometimes used to determine the temperature at which the bone was deposited, as the ratio between certain isotopes correlates with temperature. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides In one specimen, the isotope ratios in bones from different parts of the body indicated a temperature difference of no more than 4 to 5°C (7 to 9°F) between the vertebrae of the torso and the tibia of the lower leg. The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The tibia, shinbone, or shankbone is the larger and stronger of the two Bones in the Leg below the Knee in vertebrates and connects This small temperature range between the body core and the extremities was claimed by paleontologist Reese Barrick and geochemist William Showers to indicate that T. The field of geochemistry involves study of the chemical composition of the Earth and other Planets chemical processes and reactions that govern the composition rex maintained a constant internal body temperature (homeothermy) and that it enjoyed a metabolism somewhere between ectothermic reptiles and endothermic mammals. In Biology, a warm-blooded Animal species is one whose members maintain thermal Homeostasis; that is they keep their body temperature at a roughly constant [65] Other scientists have pointed out that the ratio of oxygen isotopes in the fossils today does not necessarily represent the same ratio in the distant past, and may have been altered during or after fossilization (diagenesis). In Geology and Oceanography, diagenesis is any chemical physical or biological change undergone by a Sediment after its initial deposition and during [66] Barrick and Showers have defended their conclusions in subsequent papers, finding similar results in another theropod dinosaur from a different continent and tens of millions of years earlier in time (Giganotosaurus). Giganotosaurus (meaning 'giant southern lizard' derived from the Ancient Greek gigas/γίγας meaning 'giant' notos/νότος [67] Ornithischian dinosaurs also showed evidence of homeothermy, while varanid lizards from the same formation did not. Ornithischia (ɔrnɪˈθɪskiə) or Predentata is an extinct order of beaked herbivorous Dinosaurs The name ornithischia Monitor lizards are the family Varanidae, a group of carnivorous lizards which includes the largest living lizard the Komodo dragon. Lizards are a large and widespread group of Reptiles of the order Squamata, with nearly 5000 species and ranging across all continents except [68] Even if Tyrannosaurus rex does exhibit evidence of homeothermy, it does not necessarily mean that it was endothermic. Such thermoregulation may also be explained by gigantothermy, as in some living sea turtles. Gigantothermy is a phenomenon with significance in Biology and Paleontology, whereby large bulky ectothermic (cold-blooded animals are more easily able Sea turtles ( Superfamily Chelonioidea) are Turtles found in all the world's oceans except the Arctic Ocean. [69][70]
Footprints
Two isolated fossilized footprints have been tentatively assigned to Tyrannosaurus rex. Footprints are the impressions or images left behind by a person walking The first was discovered in Philmont, New Mexico in 1983 by American geologist Charles Pillmore. New Mexico ( is a state located in the southwestern region of the United States of America. Originally thought to belong to a hadrosaurid, examination of the footprint revealed a large 'heel' unknown in ornithopod dinosaur tracks, and traces of what may have been a hallux, the dewclaw-like fourth digit of the tyrannosaur foot. Hadrosaurids or duck-billed Dinosaurs are members of the family Hadrosauridae, and include Ornithopods such as Edmontosaurus Ornithopods (ɔrˈnɪθoʊpɒd are a group of bird-hipped Dinosaurs that started out as small Bipedal running grazers and grew in size and The hallux, commonly referred to as the big toe (also as great toe or thumb toe) even though it's not actually the biggest toe on the foot of some The footprint was published as the ichnogenus Tyrannosauripus pillmorei in 1994, by Martin Lockley and Adrian Hunt. An ichnotaxon (plural ichnotaxa) is defined by the International Code of Zoological Nomenclature as "a Taxon based on the fossilized work of an organism" Lockley and Hunt suggested that it was very likely the track was made by a Tyrannosaurus rex, which would make it the first known footprint from this species. The track was made in what was once a vegetated wetland mud flat. It measures 83 centimeters (33 in) long by 71 cm (28 in) wide. [71]
A second footprint that may have been made by a Tyrannosaurus was first reported in 2007 by British paleontologist Phil Manning, from the Hell Creek Formation of Montana. The Hell Creek Formation is an intensely-studied division of Upper Cretaceous to lower Paleocene rocks in North America named for exposures studied along Hell Montana ( is a state in the Western United States. One-third of the state in the western part contains numerous mountain ranges (approximately 77 named of the northern This second track measures 76 cm (30 in) long, shorter than the track described by Lockley and Hunt. Whether or not the track was made by Tyrannosaurus is unclear, though Tyrannosaurus and Nanotyrannus are the only large theropods known to have existed in the Hell Creek Formation. Further study of the track (a full description has not yet been published) will compare the Montana track with the one found in New Mexico. [72]
Locomotion
There are two main issues concerning the locomotory abilities of Tyrannosaurus: how well it could turn; and what its maximum straight-line speed was likely to have been. Both are relevant to the debate about whether it was a hunter or a scavenger (see below).
Tyrannosaurus may have been slow to turn, possibly taking one to two seconds to turn only 45° – an amount that humans, being vertically oriented and tail-less, can spin in a fraction of a second. [73] The cause of the difficulty is rotational inertia, since much of Tyrannosaurus’ mass was some distance from its center of gravity (like a human carrying a heavy timber) - although it might have reduced the average distance by arching its back and tail and pulling its head and forelimbs close to its body (rather like the way an ice skater pulls his or her arms closer in order to spin faster). This article is about the moment of inertia of a rotating object. [74]
Scientists have produced a wide range of maximum speed estimates, mostly around 11 meters/second (25 mph), but a few as low as 5-11 meters/second (12-25 mph), and a few as high as 20 meters/second (45 mph). Researchers have to rely on various estimating techniques because, while there are many tracks of very large theropods walking, so far none have been found of very large theropods running - and this absence may indicate that they did not run. A trackway is an ancient route of travel for people and/or animals [75] Scientists who think that Tyrannosaurus was able to run point out that hollow bones and other features that would have lightened its body may have kept adult weight to a mere 5 tons or so, or that other animals like ostriches and horses with long, flexible legs are able to achieve high speeds through slower but longer strides. The Ostrich ( Struthio camelus) is a large Flightless bird native to Africa (and formerly the Middle East) The horse ( Equus caballus) is a hoofed ( Ungulate) Mammal, one of eight living species of the family Equidae. Additionally, some have argued that Tyrannosaurus had relatively larger leg muscles than any animal alive today, which could have enabled fast running (40–70 km/h or 25–45 mph). [76]
Jack Horner and Don Lessem argued in 1993 that Tyrannosaurus was slow and probably could not run (no airborne phase in mid-stride), because its ratio of femur (thigh bone) to tibia (shin bone) length was greater than 1, as in most large theropods and like a modern elephant. Elephants ( family: Elephantidae) are large land Mammals of the order Proboscidea. [52] However, Holtz (1998) noted that tyrannosaurids and some closely related groups had significantly longer distal hindlimb components (shin plus foot plus toes) relative to the femur length than most other theropods), and that tyrannosaurids and their close relatives had a tightly interlocked metatarsus that more effectively transmitted locomotory forces from the foot to the lower leg than in earlier theropods ("metatarsus" means the foot bones, which function as part of the leg in digitigrade animals). In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species The metatarsus consists of the five long Bones of the Foot, which are numbered from the medial side ( ossa metatarsalia I A digitigrade is an animal that stands or walks on its digits or toes He therefore concluded that tyrannosaurids and their close relatives were the fastest large theropods. [77]
Christiansen (1998) estimated that the leg bones of Tyrannosaurus were not significantly stronger than those of elephants, which are relatively limited in their top speed and never actually run (there is no airborne phase), and hence proposed that the dinosaur's maximum speed would have been about 11 meters/second (about 24 mph), which is about the speed of a human sprinter. But he also noted that such estimates depend on many dubious assumptions. [78]
Farlow and colleagues (1995) have argued that a 6-8 ton Tyrannosaurus would have been critically or even fatally injured if it had fallen while moving quickly, since its torso would have slammed into the ground at a deceleration of 6 g (six times the acceleration due to gravity, or about 60 meters/s²) and its tiny arms could not have reduced the impact. [7][79] However, giraffes have been known to gallop at 50 km/h (31 mph), despite the risk that they might break a leg or worse, which can be fatal even in a "safe" environment such as a zoo. The giraffe ( Giraffa camelopardalis) is an African Even-toed ungulate Mammal, the tallest of all land-living Animal Species [80][81] Thus it is quite possible that Tyrannosaurus also moved fast when necessary and had to accept such risks. [82][83]
.JPG/180px-T._rex_right_hind_foot_(med).JPG)
Most recent research on Tyrannosaurus locomotion does not narrow down speeds further than a range from 17 km/h (11 mph) to 40 km/h (25 mph), i. e. from walking or slow running to moderate-speed running. For example, a 2002 paper in the journal Nature used a mathematical model (validated by applying it to three living animals, alligators, chickens, and humans; additionally later eight more species including emus and ostriches[84]) to gauge the leg muscle mass needed for fast running (over 40 km/h [25 mph]). Nature is a prominent Scientific journal, first published on 4 November 1869 for differences between alligators and crocodiles please see Crocodilia An Alligator is a Crocodilian in the Genus The chicken ( Gallus gallus, sometimes G gallus domesticus) is a domesticated Fowl which is traditionally believed to have descended from Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus They found that proposed top speeds in excess of 40 km/h (25 mph) were unfeasible, because they would require very large leg muscles (more than approximately 40–86% of total body mass. ) Even moderately fast speeds would have required large leg muscles. This discussion is difficult to resolve, as it is unknown how large the leg muscles actually were in Tyrannosaurus. If they were smaller, only 18 km/h (~11 mph) walking/jogging might have been possible. [85][76]
A study in 2007 used computer models to estimate running speeds, based on data taken directly from fossils, and claimed that T. rex had a top running speed of 8 meters per second (18 mph). An average professional football (soccer) player would be slightly slower, while a human sprinter can reach 12 m/s (27 mph). Association football, more commonly known as football or soccer, is a Team sport played between two teams of eleven players and is widely considered Note that these computer models predict a top speed of 17. 8 m/second (about 45 mph) for a 3 kilogram (7 lb) Compsognathus[86][87] (probably a juvenile individual). Compsognathus ( Greek kompsos/κομψος; "elegant" "refined" or "dainty" and gnathos/γναθος; "jaw" [88]
Those who argue that Tyrannosaurus was incapable of running estimate the top speed of Tyrannosaurus at about 17 km/h (11 mph). This is still faster than its most likely prey species, hadrosaurids and ceratopsians. Hadrosaurids or duck-billed Dinosaurs are members of the family Hadrosauridae, and include Ornithopods such as Edmontosaurus Ceratopsia or Ceratopia (ˌsɛrəˈtɒpsiə/ /ˌsɛrəˈtoʊpiə Greek: "horned faces" is a group of herbivorous, beaked Dinosaurs [85] In addition, some advocates of the idea that Tyrannosaurus was a predator (see below) claim that tyrannosaur running speed is not important, since it may have been slow but still faster than its probable prey. [89] However, Paul and Christiansen (2000) argued that at least the later ceratopsians had upright forelimbs and the larger species may have been as fast as rhinos. Rhinoceros (raɪˈnɒsərəs often colloquially abbreviated rhino, is a name used to group five extant species of Odd-toed ungulates in the family [90] Healed Tyrannosaurus bite wounds on ceratopsian fossils are interpreted as evidence of attacks on living ceratopsians (see below). If the ceratopsians that lived alongside Tyrannosaurus were fast, that casts doubt on the argument that Tyrannosaurus did not have to be fast to catch its prey. Alternatively, perhaps Tyrannosaurus used ambush tactics to attack faster prey animals. [76] The debate about Tyrannosaurus’ speed seems far from finished.
Feeding strategies
The debate about whether Tyrannosaurus was a predator or a pure scavenger is as old as the debate about its locomotion. Scavenging, or necrophagy, is a Carnivorous Feeding behaviour in which a predator consumes Corpses or Carrion that were killed Lambe (1917) described a good skeleton of Tyrannosaurus’ close relative Gorgosaurus and concluded that it and therefore also Tyrannosaurus was a pure scavenger, because the Gorgosaurus’ teeth showed hardly any wear. Gorgosaurus (, meaning "fierce lizard" is a Genus of Tyrannosaurid Theropod Dinosaur that lived in western North [91] This argument is no longer taken seriously, because theropods replaced their teeth quite rapidly. Ever since the first discovery of Tyrannosaurus most scientists have agreed that it was a predator, although like modern large predators it would have been happy to scavenge or steal another predator's kill if it had the opportunity. [92][93]
Noted hadrosaur expert Jack Horner is currently the major advocate of the idea that Tyrannosaurus was exclusively a scavenger and did not engage in active hunting at all. Hadrosaurids or duck-billed Dinosaurs are members of the family Hadrosauridae, and include Ornithopods such as Edmontosaurus John "Jack" R Horner (born June 15, 1946) is an American paleontologist who discovered and named Maiasaura [94][52] Horner has presented several arguments to support the pure scavenger hypothesis:
- Tyrannosaurs had large olfactory bulbs and olfactory nerves (relative to their brain size). The olfactory bulb is a structure of the Vertebrate Forebrain involved in Olfaction, the perception of Odors. The olfactory nerve, or cranial nerve I, is the first of twelve Cranial nerves The specialized Olfactory receptor neurons of the olfactory nerve are located These suggest a highly developed sense of smell which could sniff out carcasses over great distances, as modern vultures do. Vultures are scavenging Birds feeding mostly on the carcasses of dead Animals Vultures are found on every continent except Antarctica and Opponents of the pure scavenger hypothesis have used the example of vultures in the opposite way, arguing that the scavenger hypothesis is implausible because the only modern pure scavengers are large gliding birds, which use their keen senses and energy-efficient gliding to cover vast areas economically. [95] However, researchers from Glasgow concluded that an ecosystem as productive as the current Serengeti would provide sufficient carrion for a large theropod scavenger, although the theropod might have had to be cold-blooded in order to get more calories from carrion than it spent on foraging (see Warm-bloodedness of dinosaurs). Glasgow (ˈglæzgoʊ is the largest city in Scotland and third most populous in the United Kingdom This article is about a geographical region for the National Park see Serengeti National Park The Serengeti ecosystem is located in north-western Tanzania Carrion (from the Latin caro, meaning meat refers to the carcass of a dead animal This article is about the unit of energy For its use in Nutrition and Food labelling regulations, see the article on Food energy. Note In this article "dinosaur" means "non-avian dinosaur" since most experts regard birds as an advanced group of dinosaurs They also suggested that modern ecosystems like Serengeti have no large terrestrial scavengers because gliding birds now do the job much more efficiently, while large theropods did not face competition for the scavenger ecological niche from gliding birds. In Ecology, a niche (pronounced nich nēsh or nish A shorthand definition of niche is how an organism makes a living [96]
- Tyrannosaur teeth could crush bone, and therefore could extract as much food (bone marrow) as possible from carcass remnants, usually the least nutritious parts. Bone marrow is the flexible tissue found in the hollow interior of Bones In adults marrow in large bones produces new Blood cells It constitutes 4% of Karen Chin and colleagues have found bone fragments in coprolites (fossilized dung) that they attribute to tyrannosaurs, but point out that a tyrannosaur's teeth were not well adapted to systematically chewing bone like hyenas do to extract marrow. A Coprolite is Fossilized animal dung Coprolites are classified as trace fossils as opposed to body fossils as they give evidence for the animal's behaviour (in The Hyaenidae is a Mammalian family of order Carnivora. The Hyaenidae family native to both African and Asian continents consists of four [97]
- Since at least some of Tyrannosaurus's potential prey could move quickly, evidence that it walked instead of ran could indicate that it was a scavenger. [94][98] On the other hand, recent analyses suggest that Tyrannosaurus, while slower than large modern terrestrial predators, may well have been fast enough to prey on large hadrosaurs and ceratopsians. Hadrosaurids or duck-billed Dinosaurs are members of the family Hadrosauridae, and include Ornithopods such as Edmontosaurus Ceratopsia or Ceratopia (ˌsɛrəˈtɒpsiə/ /ˌsɛrəˈtoʊpiə Greek: "horned faces" is a group of herbivorous, beaked Dinosaurs [85][89] It may also have used ambush tactics to attack faster prey animals. [76]
Other evidence suggests hunting behavior in Tyrannosaurus. Stevens (2006) found that the eye-sockets of tyrannosaurs are positioned so that the eyes would point forward, giving them binocular vision slightly better than that of modern hawks. Binocular vision is vision in which both Eyes are used together The term hawk can be used in several ways In strict usage in Europe and Asia, to mean any of the Species in the Subfamily He also pointed out that the tyrannosaur lineage had a history of steadily improving binocular vision. It is hard to see how natural selection would have favored this long-term trend if tyrannosaurs had been pure scavengers, which would not have needed the advanced depth perception that stereoscopic vision provides. Natural selection is the process by which favorable Heritable traits become more common in successive Generations of a Population of Depth perception is the visual ability to perceive the world in three Dimensions Although any animal capable of moving around its environment must be able to Stereopsis (from stereo meaning solidity and opsis meaning vision or Sight) is the process in Visual perception leading to the sensation [13] In modern animals, binocular vision is found mainly in predators (the principal exceptions are primates, which need it for leaping from branch to branch). A primate is a member of the biological order Primates ( Latin: "prime first rank" the group that contains Lemurs the Aye-aye
At the site where the very large tyrannosaur named Sue was found, a skeleton of the hadrosaurid Edmontosaurus annectens was also found, with healed tyrannosaur-inflicted damage on its tail vertebrae. "Sue" is the nickname given to FMNH PR2081, which is the largest most extensive and best preserved Tyrannosaurus rex specimen ever Edmontosaurus (ɛdˌmɒntəˈsɔrəs ed-MON-toh-SAWR-us meaning "Edmonton lizard" (after where it was found and Greek sauros meaning lizard A vertebra (plural vertebrae) is an individual Irregular bone in the spinal or Vertebral column ( aka ischis a flexuous and flexible column The fact that the damage seems to have healed suggests that the Edmontosaurus survived a tyrannosaur's attack on a living target, i. e. the tyrannosaur had attempted active predation. [99][100] A Triceratops was found in Mexico found with bite marks on its ilium. Triceratops (traɪˈsɛrətɒps is an extinct Genus of herbivorous ceratopsid Dinosaur which lived during the late Maastrichtian The ilium of the Pelvis is divisible into two parts the body and the ala the separation is indicated on the top surface by a curved line the arcuate line and on the These were also inflicted by a tyrannosaur and they too appear healed, indicating active predation by the tyrannosaur. [101] Tyrannosaurus also had a bite force estimated at 6,400 to 13,400 N, rivaling any other known taxon. The newton (symbol N) is the SI derived unit of Force, named after Isaac Newton in recognition of his work on Classical [15] However, further recent investigation of these purported wounds has shown that most are infections rather than injuries (or simply damage to the fossil after death) and the few injuries are too general to be indicative of intraspecific conflict. [102]
Some researchers argue that if Tyrannosaurus were a scavenger, another dinosaur had to be the top predator in the Amerasian Upper Cretaceous. Top prey were the larger marginocephalians and ornithopods. Marginocephalia ("fringed heads" is a Clade of Ornithischian Dinosaurs that includes the thick-skulled pachycephalosaurids, and horned Ornithopods (ɔrˈnɪθoʊpɒd are a group of bird-hipped Dinosaurs that started out as small Bipedal running grazers and grew in size and The other tyrannosaurids share so many characteristics that only small dromaeosaurs remain as feasible top predators. Dromaeosauridae is a family of Bird -like Theropod Dinosaurs They were small to medium-sized feathered Carnivores that flourished in the In this light, scavenger hypothesis adherents have suggested that the size and power of tyrannosaurs allowed them to steal kills from smaller predators. Kleptoparasitism or cleptoparasitism (literally Parasitism by Theft) is a form of Feeding where one animal takes Prey from another [98] Most paleontologist accept that Tyrannosaurus was both an active predator and a scavenger.
History
Henry Fairfield Osborn, president of the American Museum of Natural History, named Tyrannosaurus rex in 1905. Henry Fairfield Osborn ( August 8, 1857 – November 6, 1935) was an American Geologist, Paleontologist, and The American Museum of Natural History ( AMNH) located on the Upper West Side, Manhattan, New York, USA is one of the largest and most The generic name is derived from the Greek words τυραννος (tyrannos, meaning "tyrant") and σαυρος (sauros, meaning "lizard"). Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly Osborn used the Latin word rex, meaning "king", for the specific name. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. The full binomial therefore translates to "tyrant lizard king," emphasizing the animal's size and perceived dominance over other species of the time. [50]
Earliest finds
The vertebrae named Manospondylus by Cope in 1892 can be considered the first known specimen of Tyrannosaurus rex. Barnum Brown, assistant curator of the American Museum of Natural History, found the second Tyrannosaurus skeleton in Wyoming in 1900. Barnum Brown ( February 12, 1873 - 1963) born February 12 1873 in Carbondale Kansas. The American Museum of Natural History ( AMNH) located on the Upper West Side, Manhattan, New York, USA is one of the largest and most The State of Wyoming ( is a sparsely populated state in the western region of the United States. This specimen was originally named Dynamosaurus imperiosus in the same paper in which Tyrannosaurus rex was described. [103] Had it not been for page order, Dynamosaurus would have become the official name. The original "Dynamosaurus" material resides in the collections of the Natural History Museum, London. The Natural History Museum is one of three large Museums on Exhibition Road, South Kensington, London (the others are the Science Museum London ( ˈlʌndən is the capital and largest urban area in the United Kingdom. [104]
In total, Barnum Brown found five Tyrannosaurus partial skeletons. Brown collected his second Tyrannosaurus in 1902 and 1905 in Hell Creek, Montana. The Hell Creek Formation is an intensely-studied division of Upper Cretaceous to lower Paleocene rocks in North America named for exposures studied along Hell Montana ( is a state in the Western United States. One-third of the state in the western part contains numerous mountain ranges (approximately 77 named of the northern This is the holotype used to describe Tyrannosaurus rex Osborn, 1905. A holotype is one of several possible Biological types A type is what fixes a name to a Taxon. Henry Fairfield Osborn ( August 8, 1857 – November 6, 1935) was an American Geologist, Paleontologist, and In 1941 it was sold to the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. This article is about an organization that operates museums For the foundation which supports scientific research refer to the Carnegie Institution of Washington. The Commonwealth of Pennsylvania ( often colloquially referred to as PA (its abbreviation by natives and Northeasterners is a state located in the Northeastern Brown's fourth and largest find, also from Hell Creek, is on display in the American Museum of Natural History in New York. The American Museum of Natural History ( AMNH) located on the Upper West Side, Manhattan, New York, USA is one of the largest and most New York ( is a state in the Mid-Atlantic and Northeastern regions of the United States and is the nation's third most populous [52]
Although there are numerous skeletons in the world, only one track has been documented — at Philmont Scout Ranch in northeast New Mexico. New Mexico ( is a state located in the southwestern region of the United States of America. It was discovered in 1983 and identified and documented in 1994. [105]
Notable specimens
Sue Hendrickson, amateur paleontologist, discovered the most complete (more than 90%) and, until 2001 the largest, Tyrannosaurus fossil skeleton known in the Hell Creek Formation near Faith, South Dakota, on August 12, 1990. Sue Hendrickson (b December 2, 1949) is an American paleontologist. An amateur is generally considered a person attached to a particular pursuit study or science without formal training or pay The Hell Creek Formation is an intensely-studied division of Upper Cretaceous to lower Paleocene rocks in North America named for exposures studied along Hell Faith is a city in Meade County, South Dakota, United States. Events 1099 - First Crusade: Battle of Ascalon - Crusaders under the command of Godfrey of Bouillon defeat Fatimid Year 1990 ( MCMXC) was a Common year starting on Monday (link displays the 1990 Gregorian calendar) This Tyrannosaurus, nicknamed "Sue" in her honor, was the object of a legal battle over its ownership. In 1997 this was settled in favor of Maurice Williams, the original land owner, and the fossil collection was sold at auction for USD 7. The United States dollar ( sign: $; code: USD) is the unit of Currency of the United States; it has also been 6 million, making it the most expensive dinosaur skeleton to date. It has now been reassembled and is currently exhibited at the Field Museum of Natural History. The Field Museum of Natural History is located in Chicago, Illinois, USA. A study of this specimen's fossilized bones showed that "Sue" reached full size at age 19 and died at age 28, the longest any tyrannosaur is known to have lived. [106] The "Sue" specimen apparently died from a massive bite to the head, which could only have been inflicted by another tyrannosaur. [107] Researchers reported that a subadult and a juvenile skeleton were found in the same quarry as the "Sue" specimen, which has been used to support the hypothesis that tyrannosaurs may have lived in social groups of some kind. [108]
Another Tyrannosaurus, nicknamed "Stan", in honor of amateur paleontologist Stan Sacrison, was found in the Hell Creek Formation near Buffalo, South Dakota, in the spring of 1987. Buffalo is a town in Harding County, South Dakota, United States. After 30,000 hours of digging and preparing, a 65% complete skeleton emerged. Stan is currently on display in the Black Hills Museum of Natural History Exhibit in Hill City, South Dakota, after an extensive world tour. Hill City is the oldest existing city in Pennington County, South Dakota, United States. This tyrannosaur, too, was found to have many bone pathologies, including broken and healed ribs, a broken (and healed) neck and a spectacular hole in the back of its head, about the size of a Tyrannosaurus tooth. Both Stan and Sue were examined by Peter Larson.
In 2001, a 50% complete skeleton of a juvenile Tyrannosaurus was discovered in the Hell Creek Formation in Montana, by a crew from the Burpee Museum of Natural History of Rockford, Illinois. The Burpee Museum of Natural History is located along the Rock River in downtown Rockford, Illinois at 737 North Main Street Rockford is a mid-sized city located on both banks of the Rock River in far northern Illinois The State of Illinois ( roughly ill-i-NOY is a state of the United States of America, the 21st to be admitted to the Union. Dubbed "Jane the Rockford T-Rex," the find was initially considered the first known skeleton of the pygmy tyrannosaurid Nanotyrannus but subsequent research has revealed that it is more likely a juvenile Tyrannosaurus. Jane the nickname given to a Fossil specimen of small Tyrannosaurid Dinosaur (probably a juvenile Tyrannosaurus rex, officially known Nanotyrannus ("tiny tyrant" is a genus of Tyrannosaurid Dinosaur, and is possibly a juvenile specimen of Tyrannosaurus [109] It is the most complete and best preserved juvenile example known to date. Jane has been examined by Jack Horner, Pete Larson, Robert Bakker, Greg Erickson and several other renowned paleontologists, because of the uniqueness of her age. John "Jack" R Horner (born June 15, 1946) is an American paleontologist who discovered and named Maiasaura Peter Larson is an American Paleontologist from the Black Hills Institute of Geological Research that led the team that excavated " Sue " one of Robert T Bakker (born March 24, 1945, in Bergen County New Jersey) is an American Paleontologist who helped reshape modern theories about Palaeontology redirects here For the Scientific journal, see Palaeontology (journal. Jane is currently on exhibit at the Burpee Museum of Natural History in Rockford, Illinois. [110][111]
Also in 2001, Dr. Jack Horner discovered a specimen of T. rex around 10% larger than "Sue". Dubbed C. rex (or "Celeste" after Jack's wife), this specimen is currently under study.
In a press release on April 7, 2006, Montana State University revealed that it possessed the largest Tyrannosaurus skull yet discovered. Events 529 - First draft of Corpus Juris Civilis (a fundamental work in Jurisprudence) is issued by Eastern Roman Emperor Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Discovered in the 1960s and only recently reconstructed, the skull measures 59 inches (150 cm) long compared to the 55. 4 inches (141 cm) of “Sue’s” skull, a difference of 6. 5%. [112][113]
Appearances in popular culture
Since it was first described in 1905, Tyrannosaurus rex has become the most widely-recognized dinosaur in popular culture. Popular culture (or pop culture) is the Culture — patterns of human activity and the symbolic structures that give such activities significance and importance — It is the only dinosaur which is routinely referred to by its full scientific name (Tyrannosaurus rex) among the general public, and the scientific abbreviation T. rex has also come into wide usage (commonly misspelled "T-Rex"). [1] Robert T. Bakker notes this in The Dinosaur Heresies and explains that a name like "Tyrannosaurus rex is just irresistible to the tongue. Robert T Bakker (born March 24, 1945, in Bergen County New Jersey) is an American Paleontologist who helped reshape modern theories about The Dinosaur Heresies New Theories Unlocking the Mystery of the Dinosaurs and Their Extinction was a 1986 book published by Robert T "[6]
Museum exhibits featuring T. rex are very popular; an estimated 10,000 visitors flocked to Chicago's Field Museum on the opening day of its "Sue" exhibit in 2003. [114] T. rex has appeared numerous times on television and in films, notably (in chronological order) The Lost World, King Kong, The Land Before Time, Jurassic Park, Toy Story, Toy Story 2, Walking with Dinosaurs, and Night at the Museum. Television ( TV) is a widely used Telecommunication medium for sending ( Broadcasting) and receiving moving Images, either monochromatic The Lost World is a 1925 Silent film adaptation of Arthur Conan Doyle 's book of the same name. King Kong is a landmark Black-and-white Adventure film about a gigantic Gorilla named " Kong " and how he is captured from The Land Before Time is an Animated film, produced by Steven Spielberg 's Amblin Entertainment and directed by Don Bluth. Jurassic Park is a 1993 Science fiction film directed by Steven Spielberg and based on the novel of the same name by Michael Toy Story is a 1995 American computer-generated Comedy film, directed by John Lasseter and starring Tom Hanks Toy Story 2 is a 1999 Academy-Award -nominated CGI Film, the Sequel to Toy Story; the third Walking with Dinosaurs was a six-part Television series produced by the BBC, narrated by Kenneth Branagh, and first aired in the UK Night at the Museum is a 2006 American Adventure Comedy film. A number of books and comic strips, including Calvin and Hobbes, have also featured Tyrannosaurus, which is typically portrayed as the biggest and most terrifying carnivore of all. A comic strip is a sequence of drawings that tells a story Currently in the Western world, most comic strips are written and drawn by a Comics artist Calvin and Hobbes is a Comic strip written and illustrated by Bill Watterson, following the humorous antics of Calvin, an imaginative At least one musical group, the band T.Rex, is named after the species. TRex (occasionally spelled T Rex or T-Rex) were an English rock band fronted by guitarist singer and songwriter Marc Bolan. Tyrannosaurus-related toys, including numerous video games and other merchandise, remain popular. This article is about playthings For other uses of the term see Toy (disambiguation. A video game is a Game that involves interaction with a User interface to generate visual feedback on a video device. Various businesses have capitalized on the popularity of Tyrannosaurus rex by using it in advertisements. Advertising is a form of Communication that typically attempts to persuade potential Customers to Purchase or to consume more of a particular Brand
References
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- ^ a b c d Hajdul, R. (1997). Tendons. Dinosaur Cards. Orbis Publishing Ltd. D36044311.
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- ^ "The bigger they come, the harder they fall" New Scientist, October 7, 1995, p. Events 3761 BC - The epoch (origin of the modern Hebrew calendar ( Proleptic Julian calendar) Year 1995 ( MCMXCV) was a Common year starting on Sunday. Events of 1995 18.
- ^ Giraffe. WildlifeSafari. info. Retrieved on 2006-04-29. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1429 - Joan of Arc arrives to relieve the Siege of Orleans.
- ^ The History of Woodland Park Zoo - Chapter 4. Retrieved on 2006-04-29. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1429 - Joan of Arc arrives to relieve the Siege of Orleans.
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See also
- Farlow, J. O. (2000). "Theropod Locomotion". American Zoologist 40 (4): 640–663. The Society for Integrative and Comparative Biology. doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. - a good survey of research
External links
- Tyrannosauridae "Tree of Life" page, very comprehensive survey by major authority Tom Holtz.
- "The secret of T. rex's colossal size: a teenage growth spurt", The Guardian, August 12, 2004. Events 1099 - First Crusade: Battle of Ascalon - Crusaders under the command of Godfrey of Bouillon defeat Fatimid "MMIV" redirects here For the Modest Mouse album see " Baron von Bullshit Rides Again "
- Tyrannosaurus in the Dino Directory
- Sue's homepage
- Stan's homepage
- Tree of Life discussing Tyrannosauridae "Tree of Life" page, very comprehensive survey by major authority Tom Holtz.
- Unearthing Tyrannosaurus rex
- T.rex juvenile Jane
- NBCI's Taxonomy Browser
- Cretaceous Hell Creek Faunal Facies is an example of one tyrannosaur environment, in the Hell Creek Formation of Montana
- Bristol University study on bite forces of predators
- Museum of Unnatural Mystery – Bite force etc. of T. rex
- Stanford University on bite force of T. rex
- How Tyrannosaurus might have had sex
- Recent Discovery of Soft Tissue
The Hell Creek Formation is an intensely-studied division of Upper Cretaceous to lower Paleocene rocks in North America named for exposures studied along Hell Montana ( is a state in the Western United States. One-third of the state in the western part contains numerous mountain ranges (approximately 77 named of the northern
Dictionary
tyrannosaurus
-noun
- A large carnivorous dinosaur, of the genus Tyrannosaurus, found in North America during the Cretaceous period.
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