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Barosaurus Lentus1
''Barosaurus'' ( ) was a giant, long-tailed, long-necked, plant-eating sauropod dinosaur closely related to the more familiar ''Diplodocus''. Remains have been found in the Morrison Formation from the Upper Jurassic Period of Utah and South Dakota. It is present in stratigraphic zones 2–5.Foster, J. (2007). "Appendix." ''Jurassic West: The Dinosaurs of the Morrison Formation and Their World''. Indiana University Press. pp. 327-329. The composite term ''Barosaurus'' comes from the Greek words ''barys'' (βαρυς) meaning "heavy" and ''sauros'' (σαυρος) meaning "lizard"; thus "heavy lizard". Description ''Barosaurus'' was an enormous animal, with some adults measuring about in length and weighing about 12–20 metric tons (13–22 short tons).Paul, G.S., 2016, ''The Princeton Field Guide to Dinosaurs 2nd edition'', Princeton University Press p. 213 There are some indications of even larger individuals, such as the enormous cervical vertebra from the BYU 902 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of dinosau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Short Ton
The short ton (symbol tn) is a measurement unit equal to . It is commonly used in the United States, where it is known simply as a ton, although the term is ambiguous, the single word being variously used for short, long, and metric ton. The various tons are defined as units of mass.Butcher, Crown and Gentry, NIST Special Publication 1038, The International System of Units (SI) – Conversion Factors for General Use, 2006 They are sometimes used as units of weight, the force exerted by a mass at standard gravity (e.g., short ton-force). One short ton exerts a weight at one standard gravity of 2,000 pound-force (lbf). United States In the United States, a short ton is usually known simply as a "ton", without distinguishing it from the tonne (), known there as the "metric ton", or the long ton also known as the "imperial ton" (). There are, however, some U.S. applications where unspecified ''tons'' normally mean long tons (for example, naval ships) or metric tons (world grain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manus (anatomy)
The manus (Latin for ''hand'', plural manus) is the zoological term for the distal portion of the fore limb of an animal. In tetrapods, it is the part of the pentadactyl limb that includes the metacarpals and digits (phalanges). During evolution, it has taken many forms and served a variety of functions. It can be represented by the hand of primates, the lower front limb of hoofed animals or the fore paw and is represented in the wing of birds, bats and prehistoric flying reptiles (pterosaurs), the flipper of marine mammals and the 'paddle' of extinct marine reptiles, such as plesiosaurs and ichthyosaurs. In cephalopods, the ''manus'' is the end, broader part of a tentacle, and its suckers are often larger and arranged differently from those on the other arms. See also *Pes (anatomy) The pes (Latin for ''foot'') is the zoological term for the distal portion of the hind limb of tetrapod animals. It is the part of the pentadactyl limb that includes the metatarsals and digits (p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digitigrade
In terrestrial vertebrates, digitigrade () locomotion is walking or running on the toes (from the Latin ''digitus'', 'finger', and ''gradior'', 'walk'). A digitigrade animal is one that stands or walks with its toes (metatarsals) touching the ground, and the rest of its foot lifted. Digitigrades include walking birds (what many assume to be bird knees are actually ankles), cats, dogs, and many other mammals, but not plantigrades or unguligrades. Digitigrades generally move more quickly and quietly than other animals. There are anatomical differences between the limbs of plantigrades, like humans, and both unguligrade and digitigrade limbs. Digitigrade and unguligrade animals have relatively long carpals and tarsals, and the bones which would correspond to the human ankle are thus set much higher in the limb than in a human. In a digitigrade animal, this effectively lengthens the foot, so much so that what are often thought of as a digitigrade animal's "hands" and "feet" correspon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpal
In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones are analogous to the metatarsal bones in the foot. Structure The metacarpals form a transverse arch to which the rigid row of distal carpal bones are fixed. The peripheral metacarpals (those of the thumb and little finger) form the sides of the cup of the palmar gutter and as they are brought together they deepen this concavity. The index metacarpal is the most firmly fixed, while the thumb metacarpal articulates with the trapezium and acts independently from the others. The middle metacarpals are tightly united to the carpus by intrinsic interlocking bone elements at their bases. The ring metacarpal is somewhat more mobile while the fifth metacarpal is semi-independent.Tubiana ''et al'' 1998, p 11 Each metacarpal bone consists of a bod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpal
The carpal bones are the eight small bones that make up the wrist (or carpus) that connects the hand to the forearm. The term "carpus" is derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy, the main role of the wrist is to facilitate effective positioning of the hand and powerful use of the extensors and flexors of the forearm, and the mobility of individual carpal bones increase the freedom of movements at the wrist.Kingston 2000, pp 126-127 In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those of the metacarpus do. The corresponding part of the foot is the tarsus. The carpal bones allow the wrist to move and rotate vertically. Structure Bones The eight carpal bones may be conceptually organized as either two transverse rows, or three longitudinal columns. When c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chevron (anatomy)
A haemal arch also known as a chevron, is a bony arch on the ventral side of a tail vertebra of a vertebrate. The canal formed by the space between the arch and the vertebral body is the haemal canal. A spinous ventral process emerging from the haemal arch is referred to as the haemal spine. Blood vessels to and from the tail run through the arch. In reptiles, the caudofemoralis longus muscle, one of the main muscles involved in locomotion, attaches to the lateral sides of the haemal arches. In 1956, Alfred Sherwood Romer hypothesized that the position of the first haemal arch was sexually dimorphic in crocodilians and dinosaurs. However, subsequent research established that the size and position of the first haemal arch was not sexually dimorphic in crocodilians and found no evidence of significant variation in tyrannosaurid dinosaurs, indicating that haemal arches could not be used to distinguish between sexes after all. Haemal arches play an important role in the taxonomy of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caudal Vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch (in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinous Process
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch (i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cervical Vertebra
In tetrapods, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sauropsid species, the cervical vertebrae bear cervical ribs. In lizards and saurischian dinosaurs, the cervical ribs are large; in birds, they are small and completely fused to the vertebrae. The vertebral transverse processes of mammals are homologous to the cervical ribs of other amniotes. Most mammals have seven cervical vertebrae, with the only three known exceptions being the manatee with six, the two-toed sloth with five or six, and the three-toed sloth with nine. In humans, cervical vertebrae are the smallest of the true vertebrae and can be readily distinguished from those of the thoracic or lumbar regions by the presence of a foramen (hole) in each transverse process, through which the vertebral artery, vertebral veins, and inferio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apatosaurus
''Apatosaurus'' (; meaning "deceptive lizard") is a genus of herbivorous sauropod dinosaur that lived in North America during the Late Jurassic period. Othniel Charles Marsh described and named the first-known species, ''A. ajax'', in 1877, and a second species, ''A. louisae'', was discovered and named by William H. Holland in 1916. ''Apatosaurus'' lived about 152 to 151 million years ago (mya), during the late Kimmeridgian to early Tithonian age, and are now known from fossils in the Morrison Formation of modern-day Colorado, Oklahoma, New Mexico, Wyoming, and Utah in the United States. ''Apatosaurus'' had an average length of , and an average mass of . A few specimens indicate a maximum length of 11–30% greater than average and a mass of approximately . The cervical vertebrae of ''Apatosaurus'' are less elongated and more heavily constructed than those of ''Diplodocus'', a diplodocid like ''Apatosaurus'', and the bones of the leg are much stockier despite being longer, imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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