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Camarasauridae

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72-464: Camarasauridae is a family of sauropod dinosaurs . Among sauropods, camarasaurids are small to medium-sized, with relatively short necks. They are visually identifiable by a short skull with large nares, and broad, spatulate teeth filling a thick jaw. Based on cervical vertebrae and cervical rib biomechanics, camarasaurids most likely moved their necks in a vertical, rather than horizontal, sweeping motion, in contrast to most diplodocids. Camarasauridae

144-671: A basal eusauropod. Oplosaurus , from the Early Cretaceous of the United Kingdom , has been suggested to be a camarasaurid, but as it is only known from a tooth, its position within Eusauropoda is difficult to determine. Tehuelchesaurus , from the Late Jurassic of Argentina , has been considered a camarasaurid in some studies, but a wide range of other phylogenetic positions have been proposed, including

216-495: A basal titanosauriform. The tracks are wide-gauge, and the grouping as close to Sauropodichnus is also supported by the manus-to-pes distance, the morphology of the manus being kidney bean-shaped, and the morphology of the pes being subtriangular. It cannot be identified whether the footprints of the herd were caused by juveniles or adults, because of the lack of previous trackway individual age identification. Generally, sauropod trackways are divided into three categories based on

288-420: A bipedal posture at times, there would be evidence of stress fractures in the forelimb 'hands'. However, none were found after they examined a large number of sauropod skeletons. Heinrich Mallison (in 2009) was the first to study the physical potential for various sauropods to rear into a tripodal stance. Mallison found that some characters previously linked to rearing adaptations were actually unrelated (such as

360-526: A characteristic feature of all sauropods. These air spaces reduced the overall weight of the massive necks that the sauropods had, and the air-sac system in general, allowing for a single-direction airflow through stiff lungs, made it possible for the sauropods to get enough oxygen. This adaptation would have advantaged sauropods particularly in the relatively low oxygen conditions of the Jurassic and Early Cretaceous. The bird-like hollowing of sauropod bones

432-770: A close relationship to Omeisaurus , a position in Turiasauria , or as a non-camarasaurid basal macronarian. Bellusaurus , which is only known from juvenile remains, may be a camarasaurid, though it has also been considered a basal macronarian, turiasaur, or mamenchisaurid. In 1970, Rodney Steel took an expansive concept of Camarasauridae, encompassing all sauropods then known except diplodocoids and titanosaurs. In 1990, John S. McIntosh regarded Camarasauridae as made up of two subfamilies: Camarasaurinae, containing Camarasaurus , Aragosaurus , Euhelopus , and Tienshanosaurus , and Opisthocoelicaudiinae, containing Opisthocoelicaudia and Chondrosteosaurus . Dashanpusaurus , from

504-402: A great number of adaptations in their skeletal structure. Some sauropods had as many as 19 cervical vertebrae , whereas almost all mammals are limited to only seven. Additionally, each vertebra was extremely long and had a number of empty spaces in them which would have been filled only with air. An air-sac system connected to the spaces not only lightened the long necks, but effectively increased

576-422: A large energy saving for such a large animal. Reconstructions of the necks of Diplodocus and Apatosaurus have therefore often portrayed them in near-horizontal, so-called "neutral, undeflected posture". However, research on living animals demonstrates that almost all extant tetrapods hold the base of their necks sharply flexed when alert, showing that any inference from bones about habitual "neutral postures"

648-513: A part in the different feeding and herding strategies. Since the segregation of juveniles and adults must have taken place soon after hatching, and combined with the fact that sauropod hatchlings were most likely precocial , Myers and Fiorillo concluded that species with age-segregated herds would not have exhibited much parental care. On the other hand, scientists who have studied age-mixed sauropod herds suggested that these species may have cared for their young for an extended period of time before

720-490: A population of sauropods isolated on an island of the late Jurassic in what is now the Langenberg area of northern Germany . The diplodocoid sauropod Brachytrachelopan was the shortest member of its group because of its unusually short neck. Unlike other sauropods, whose necks could grow to up to four times the length of their backs, the neck of Brachytrachelopan was shorter than its backbone. Fossils from perhaps

792-495: A position much above the shoulders for exploring the area or reaching higher. Another proposed function of the sauropods' long necks was essentially a radiator to deal with the extreme amount of heat produced from their large body mass. Considering that the metabolism would have been doing an immense amount of work, it would certainly have generated a large amount of heat as well, and elimination of this excess heat would have been essential for survival. It has also been proposed that

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864-483: A review of the evidence for various herd types, Myers and Fiorillo attempted to explain why sauropods appear to have often formed segregated herds. Studies of microscopic tooth wear show that juvenile sauropods had diets that differed from their adult counterparts, so herding together would not have been as productive as herding separately, where individual herd members could forage in a coordinated way. The vast size difference between juveniles and adults may also have played

936-404: A stance to be unstable. Diplodocids, on the other hand, appear to have been well adapted for rearing up into a tripodal stance. Diplodocids had a center of mass directly over the hips, giving them greater balance on two legs. Diplodocids also had the most mobile necks of sauropods, a well-muscled pelvic girdle, and tail vertebrae with a specialised shape that would allow the tail to bear weight at

1008-455: A stilt-walker principle (suggested by amateur scientist Jim Schmidt) in which the long legs of adult sauropods allowed them to easily cover great distances without changing their overall mechanics. Along with other saurischian dinosaurs (such as theropods , including birds), sauropods had a system of air sacs , evidenced by indentations and hollow cavities in most of their vertebrae that had been invaded by them. Pneumatic, hollow bones are

1080-414: A wide gauge and lack of any claws or digits on the forefeet. Occasionally, only trackways from the forefeet are found. Falkingham et al. used computer modelling to show that this could be due to the properties of the substrate. These need to be just right to preserve tracks. Differences in hind limb and fore limb surface area, and therefore contact pressure with the substrate, may sometimes lead to only

1152-429: Is a notable size increase among sauropodomorphs, although scanty remains of this period make interpretation conjectural. There is one definite example of a small derived sauropodomorph: Anchisaurus , under 50 kg (110 lb), even though it is closer to the sauropods than Plateosaurus and Riojasaurus , which were upwards of 1 t (0.98 long tons; 1.1 short tons) in weight. Evolving from sauropodomorphs,

1224-453: Is deeply unreliable. Meanwhile, computer modeling of ostrich necks has raised doubts over the flexibility needed for stationary grazing. Sauropod trackways and other fossil footprints (known as "ichnites") are known from abundant evidence present on most continents. Ichnites have helped support other biological hypotheses about sauropods, including general fore and hind foot anatomy (see Limbs and feet above). Generally, prints from

1296-898: Is evidence that they preferred wet and coastal habitats. Sauropod footprints are commonly found following coastlines or crossing floodplains, and sauropod fossils are often found in wet environments or intermingled with fossils of marine organisms. A good example of this would be the massive Jurassic sauropod trackways found in lagoon deposits on Scotland 's Isle of Skye . Studies published in 2021 suggest sauropods could not inhabit polar regions. This study suggests they were largely confined to tropical areas and had metabolisms that were very different to those of other dinosaurs, perhaps intermediate between mammals and reptiles. New studies published by Taia Wyenberg-henzler in 2022 suggest that sauropods in North America declined due to undetermined reasons in regards to their niches and distribution during

1368-632: Is shown in the fossil record. Moreover, it must be determined as to whether sauropod declines in North America was the result of a change in preferred flora that sauropods ate, climate, or other factors. It is also suggested in this same study that iguanodontians and hadrosauroids took advantage of recently vacated niches left by a decline in sauropod diversity during the late Jurassic and the Cretaceous in North America. Many lines of fossil evidence, from both bone beds and trackways, indicate that sauropods were gregarious animals that formed herds . However,

1440-407: Is the only taxon uncontroversially regarded as a valid genus of camarasaurid. It contains four species: C. grandis , C. lentus , C. lewisi , and C. supremus . C. lewisi may represent a distinct genus, Cathetosaurus . Lourinhasaurus , the type species of which was formerly assigned to Camarasaurus , is regarded as a camarasaurid by most studies, though it has also been considered to be

1512-421: Is unknown. The claw was largest (as well as tall and laterally flattened) in diplodocids, and very small in brachiosaurids, some of which seem to have lost the claw entirely based on trackway evidence. Titanosaurs may have lost the thumb claw completely (with the exception of early forms, such as Janenschia ). Titanosaurs were most unusual among sauropods, as, across their history as a clade, they lost not just

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1584-489: The African elephant , can only reach lengths of 7.3 metres (24 ft). Others, like the brachiosaurids , were extremely tall, with high shoulders and extremely long necks. The tallest sauropod was the giant Barosaurus specimen at 22 m (72 ft) tall. By comparison, the giraffe , the tallest of all living land animals, is only 4.8 to 5.6 metres (15.74 to 18.3 ft) tall. The best evidence indicates that

1656-742: The Early Jurassic . Isanosaurus and Antetonitrus were originally described as Triassic sauropods, but their age, and in the case of Antetonitrus also its sauropod status, were subsequently questioned. Sauropod-like sauropodomorph tracks from the Fleming Fjord Formation ( Greenland ) might, however, indicate the occurrence of the group in the Late Triassic . By the Late Jurassic (150 million years ago), sauropods had become widespread (especially

1728-473: The blue whale in size. The weight of Amphicoelias fragillimus was estimated at 122.4 metric tons with lengths of up to nearly 60 meters but 2015 research argued that these estimates were based on a diplodocid rather than the more modern rebbachisaurid, suggesting a much shorter length of 35–40 meters with mass between 80–120 tons. Additional finds indicate a number of species likely reached or exceeded weights of 40 tons. The largest land animal alive today,

1800-430: The bush elephant , weighs no more than 10.4 metric tons (11.5 short tons). Among the smallest sauropods were the primitive Ohmdenosaurus (4 m, or 13 ft long), the dwarf titanosaur Magyarosaurus (6 m or 20 ft long), and the dwarf brachiosaurid Europasaurus , which was 6.2 meters long as a fully-grown adult. Its small stature was probably the result of insular dwarfism occurring in

1872-555: The diplodocids and brachiosaurids ). By the Late Cretaceous , one group of sauropods, the titanosaurs , had replaced all others and had a near-global distribution. However, as with all other non-avian dinosaurs alive at the time, the titanosaurs died out in the Cretaceous–Paleogene extinction event . Fossilised remains of sauropods have been found on every continent, including Antarctica . The name Sauropoda

1944-497: The rorquals , such as the blue whale . But, unlike whales, sauropods were primarily terrestrial animals . Their body structure did not vary as much as other dinosaurs, perhaps due to size constraints, but they displayed ample variety. Some, like the diplodocids , possessed tremendously long tails, which they may have been able to crack like a whip as a signal or to deter or injure predators, or to make sonic booms . Supersaurus , at 33 to 34 metres (108 to 112 ft) long,

2016-458: The 1970s, the effects of sauropod air sacs on their supposed aquatic lifestyle began to be explored. Paleontologists such as Coombs and Bakker used this, as well as evidence from sedimentology and biomechanics , to show that sauropods were primarily terrestrial animals. In 2004, D.M. Henderson noted that, due to their extensive system of air sacs, sauropods would have been buoyant and would not have been able to submerge their torsos completely below

2088-432: The 19th and early 20th centuries concluded that sauropods were too large to have supported their weight on land, and therefore that they must have been mainly aquatic . Most life restorations of sauropods in art through the first three quarters of the 20th century depicted them fully or partially immersed in water. This early notion was cast in doubt beginning in the 1950s, when a study by Kermack (1951) demonstrated that, if

2160-496: The Middle Jurassic of China, was originally described as a camarasaurid, but was subsequently found to be a basal macronarian by phylogenetic analysis. Several skeletal features have been used to characterize the camarasaurids. In the skull, these include an external narial diameter approximately 40% of the long-axis length of the skull, an arched internarial bar, a short muzzle anterior to the nares, and maxillary shelf. In

2232-466: The Middle Triassic of Argentina, weighed approximately 1 kg (2.2 lb) or less. These evolved into saurischia, which saw a rapid increase of bauplan size, although more primitive members like Eoraptor , Panphagia , Pantydraco , Saturnalia and Guaibasaurus still retained a moderate size, possibly under 10 kg (22 lb). Even with these small, primitive forms, there

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2304-550: The airflow through the trachea, helping the creatures to breathe in enough air. By evolving vertebrae consisting of 60% air, the sauropods were able to minimize the amount of dense, heavy bone without sacrificing the ability to take sufficiently large breaths to fuel the entire body with oxygen. According to Kent Stevens, computer-modeled reconstructions of the skeletons made from the vertebrae indicate that sauropod necks were capable of sweeping out large feeding areas without needing to move their bodies, but were unable to be retracted to

2376-418: The animal were submerged in several metres of water, the pressure would be enough to fatally collapse the lungs and airway. However, this and other early studies of sauropod ecology were flawed in that they ignored a substantial body of evidence that the bodies of sauropods were heavily permeated with air sacs . In 1878, paleontologist E.D. Cope had even referred to these structures as "floats". Beginning in

2448-694: The appendicular skeleton. Broadly speaking, camarasaurids occupied a distribution limited to the Laurasian continent during the Upper Jurassic . Most currently accepted camarasaurid specimens have been discovered in the Morrison Formation of North America, however some specimens from the African Tendaguru Formation have been speculated to belong to the genus Camarasaurus , and the closely related Lourinhasaurus

2520-523: The distance between opposite limbs: narrow gauge, medium gauge, and wide gauge. The gauge of the trackway can help determine how wide-set the limbs of various sauropods were and how this may have impacted the way they walked. A 2004 study by Day and colleagues found that a general pattern could be found among groups of advanced sauropods, with each sauropod family being characterised by certain trackway gauges. They found that most sauropods other than titanosaurs had narrow-gauge limbs, with strong impressions of

2592-405: The end of the Jurassic and into the latest Cretaceous. Why this is remains unclear, but some similarities in feeding niches between iguanodontians, hadrosauroids and sauropods have been suggested and may have resulted in some competition. However, this cannot fully explain the full decline in distribution of sauropods, as competitive exclusion would have resulted in a much more rapid decline than what

2664-423: The external claw but also completely lost the digits of the front foot. Advanced titanosaurs had no digits or digit bones, and walked only on horseshoe-shaped "stumps" made up of the columnar metacarpal bones. Print evidence from Portugal shows that, in at least some sauropods (probably brachiosaurids), the bottom and sides of the forefoot column was likely covered in small, spiny scales, which left score marks in

2736-488: The flesh miss these facts, inaccurately depicting sauropods with hooves capping the claw-less digits of the feet, or more than three claws or hooves on the hands. The proximal caudal vertebrae are extremely diagnostic for sauropods. The sauropods' most defining characteristic was their size. Even the dwarf sauropods (perhaps 5 to 6 metres, or 20 feet long) were counted among the largest animals in their ecosystem . Their only real competitors in terms of size are

2808-601: The forefeet are much smaller than the hind feet, and often crescent-shaped. Occasionally ichnites preserve traces of the claws, and help confirm which sauropod groups lost claws or even digits on their forefeet. Sauropod tracks from the Villar del Arzobispo Formation of early Berriasian age in Spain support the gregarious behaviour of the group. The tracks are possibly more similar to Sauropodichnus giganteus than any other ichnogenera, although they have been suggested to be from

2880-483: The forefeet trackways being preserved. In a study published in PLoS ONE on October 30, 2013, by Bill Sellers , Rodolfo Coria , Lee Margetts et al. , Argentinosaurus was digitally reconstructed to test its locomotion for the first time. Before the study, the most common way of estimating speed was through studying bone histology and ichnology . Commonly, studies about sauropod bone histology and speed focus on

2952-418: The forefoot bone ( metacarpal ) columns in eusauropods was semi-circular, so sauropod forefoot prints are horseshoe-shaped. Unlike elephants, print evidence shows that sauropods lacked any fleshy padding to back the front feet, making them concave. The only claw visible in most sauropods was the distinctive thumb claw (associated with digit I). Almost all sauropods had such a claw, though what purpose it served

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3024-401: The gait and speed of Argentinosaurus , the study performed a musculoskeletal analysis. The only previous musculoskeletal analyses were conducted on hominoids , terror birds , and other dinosaurs . Before they could conduct the analysis, the team had to create a digital skeleton of the animal in question, show where there would be muscle layering, locate the muscles and joints, and finally find

3096-447: The head in such a posture for long would have used some half of its energy intake. Further, to move blood to such a height—dismissing posited auxiliary hearts in the neck —would require a heart 15 times as large as of a similar-sized whale. The above have been used to argue that the long neck must instead have been held more or less horizontally, presumed to enable feeding on plants over a wide area with less need to move about, yielding

3168-490: The history of their study, scientists, such as Osborn , have speculated that sauropods could rear up on their hind legs, using the tail as the third 'leg' of a tripod. A skeletal mount depicting the diplodocid Barosaurus lentus rearing up on its hind legs at the American Museum of Natural History is one illustration of this hypothesis. In a 2005 paper, Rothschild and Molnar reasoned that if sauropods had adopted

3240-418: The large thumb claw on the forefeet. Medium gauge trackways with claw impressions on the forefeet probably belong to brachiosaurids and other primitive titanosauriformes , which were evolving wider-set limbs but retained their claws. Primitive true titanosaurs also retained their forefoot claw but had evolved fully wide gauge limbs. Wide gauge limbs were retained by advanced titanosaurs, trackways from which show

3312-600: The largest dinosaur ever found were discovered in 2012 in the Neuquén Province of northwest Patagonia, Argentina. It is believed that they are from a titanosaur, which were amongst the largest sauropods. On or shortly before 29 March 2017 a sauropod footprint about 5.6 feet (1.7 meters) long was found at Walmadany in the Kimberley Region of Western Australia. The report said that it was the biggest known yet. In 2020 Molina-Perez and Larramendi estimated

3384-462: The long necks would have cooled the veins and arteries going to the brain, avoiding excessively heated blood from reaching the head. It was in fact found that the increase in metabolic rate resulting from the sauropods' necks was slightly more than compensated for by the extra surface area from which heat could dissipate. When sauropods were first discovered, their immense size led many scientists to compare them with modern-day whales . Most studies in

3456-597: The makeup of the herds varied between species. Some bone beds, for example a site from the Middle Jurassic of Argentina , appear to show herds made up of individuals of various age groups, mixing juveniles and adults. However, a number of other fossil sites and trackways indicate that many sauropod species travelled in herds segregated by age, with juveniles forming herds separate from adults. Such segregated herding strategies have been found in species such as Alamosaurus , Bellusaurus and some diplodocids . In

3528-519: The most massive were Argentinosaurus (65–80 metric tons ), Mamenchisaurus sinocanadorum (60-80 metric tons ), the giant Barosaurus specimen (60-80+ metric tons ) and Patagotitan with Puertasaurus (50-55  metric tons ). Meanwhile, 'mega-sauropods' such as Bruhathkayosaurus has long been scrutinized due to controversial debates on its validity, but recent photos re-surfacing in 2022 have legitimized it, allowing for more updated estimates that range between 110–170 tons, rivaling

3600-641: The muscle properties before finding the gait and speed. The results of the biomechanics study revealed that Argentinosaurus was mechanically competent at a top speed of 2 m/s (5 mph) given the great weight of the animal and the strain that its joints were capable of bearing. The results further revealed that much larger terrestrial vertebrates might be possible, but would require significant body remodeling and possible sufficient behavioral change to prevent joint collapse. Sauropods were gigantic descendants of surprisingly small ancestors. Basal dinosauriformes, such as Pseudolagosuchus and Marasuchus from

3672-431: The neck, and the head was evolved to be very small and light, losing the ability to orally process food. By reducing their heads to simple harvesting tools that got the plants into the body, the sauropods needed less power to lift their heads, and thus were able to develop necks with less dense muscle and connective tissue. This drastically reduced the overall mass of the neck, enabling further elongation. Sauropods also had

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3744-584: The point it touched the ground. Mallison concluded that diplodocids were better adapted to rearing than elephants , which do so occasionally in the wild. He also argues that stress fractures in the wild do not occur from everyday behaviour, such as feeding-related activities (contra Rothschild and Molnar). There is little agreement over how sauropods held their heads and necks, and the postures they could achieve in life. Whether sauropods' long necks could be used for browsing high trees has been questioned based on calculations suggesting that just pumping blood up to

3816-532: The postcranial skeleton, which holds many unique features, such as an enlarged process on the ulna , a wide lobe on the ilia , an inward-slanting top third of the femur , and an extremely ovoid femur shaft. Those features are useful when attempting to explain trackway patterns of graviportal animals. When studying ichnology to calculate sauropod speed, there are a few problems, such as only providing estimates for certain gaits because of preservation bias , and being subject to many more accuracy problems. To estimate

3888-642: The prints. In titanosaurs, the ends of the metacarpal bones that contacted the ground were unusually broad and squared-off, and some specimens preserve the remains of soft tissue covering this area, suggesting that the front feet were rimmed with some kind of padding in these species. Matthew Bonnan has shown that sauropod dinosaur long bones grew isometrically : that is, there was little to no change in shape as juvenile sauropods became gigantic adults. Bonnan suggested that this odd scaling pattern (most vertebrates show significant shape changes in long bones associated with increasing weight support) might be related to

3960-434: The rest of the axial skeleton, these include flat ventral faces on the cervical vertebrae, a triangular flare to the neural spines of the middle and posterior dorsal vertebrae, and a concave posterior surface to the anterior thoracic ribs, as well as an external haemal canal across the anterior vertebrae of the tail. A reduction to two carpals, long metacarpals relative to the radius, and a twisted ischial shaft serve to identify

4032-422: The rest of their body), and four thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land. Well-known genera include Apatosaurus , Argentinosaurus , Alamosaurus , Brachiosaurus , Camarasaurus , Diplodocus , and Mamenchisaurus . The oldest known unequivocal sauropod dinosaurs are known from

4104-621: The sauropods were huge. Their giant size probably resulted from an increased growth rate made possible by tachymetabolic endothermy , a trait which evolved in sauropodomorphs. Once branched into sauropods, sauropodomorphs continued steadily to grow larger, with smaller sauropods, like the Early Jurassic Barapasaurus and Kotasaurus , evolving into even larger forms like the Middle Jurassic Mamenchisaurus and Patagosaurus . Responding to

4176-401: The scientists, the specializing of their diets helped the different herbivorous dinosaurs to coexist. Sauropod necks have been found at over 15 metres (49 ft) in length, a full six times longer than the world record giraffe neck. Enabling this were a number of essential physiological features. The dinosaurs' overall large body size and quadrupedal stance provided a stable base to support

4248-451: The shorter hind legs free of the bottom, and using the front limbs to punt forward. However, due to their body proportions, floating sauropods would also have been very unstable and maladapted for extended periods in the water. This mode of aquatic locomotion , combined with its instability, led Henderson to refer to sauropods in water as "tipsy punters". While sauropods could therefore not have been aquatic as historically depicted, there

4320-409: The sides to create a wide foot as in elephants, the manus bones of sauropods were arranged in fully vertical columns, with extremely reduced finger bones (though it is not clear if the most primitive sauropods, such as Vulcanodon and Barapasaurus , had such forefeet). The front feet were so modified in eusauropods that individual digits would not have been visible in life. The arrangement of

4392-477: The size estimates of A. fragillimus may have been highly exaggerated. The longest dinosaur known from reasonable fossils material is probably Argentinosaurus huinculensis with length estimates of 35 metres (115 ft) to 36 metres (118 ft) according to the most recent researches. However the giant Barosaurus specimen BYU 9024 might have been even larger reaching lengths of 45–48 meters (148–157 ft). The longest terrestrial animal alive today,

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4464-537: The size of the animal at 31 meters (102 ft) and 72 tonnes (79.4 short tons) based on the 1.75 meter (5.7 ft) long footprint. As massive quadrupeds , sauropods developed specialized "graviportal" (weight-bearing) limbs. The hind feet were broad, and retained three claws in most species. Particularly unusual compared with other animals were the highly modified front feet ( manus ). The front feet of sauropods were very dissimilar from those of modern large quadrupeds, such as elephants . Rather than splaying out to

4536-467: The surface of the water; in other words, they would float, and would not have been in danger of lung collapse due to water pressure when swimming. Evidence for swimming in sauropods comes from fossil trackways that have occasionally been found to preserve only the forefeet (manus) impressions. Henderson showed that such trackways can be explained by sauropods with long forelimbs (such as macronarians ) floating in relatively shallow water deep enough to keep

4608-434: The tip, narrow at the neck) teeth. They had tiny heads, massive bodies, and most had long tails. Their hind legs were thick, straight, and powerful, ending in club-like feet with five toes, though only the inner three (or in some cases four) bore claws. Their forelimbs were rather more slender and typically ended in pillar-like hands built for supporting weight; often only the thumb bore a claw. Many illustrations of sauropods in

4680-413: The tooth affected how long it took for a new tooth to grow. Camarasaurus 's teeth took longer to grow than those for Diplodocus because they were larger. It was also noted by D'Emic and his team that the differences between the teeth of the sauropods also indicated a difference in diet. Diplodocus ate plants low to the ground and Camarasaurus browsed leaves from top and middle branches. According to

4752-415: The wide-set hip bones of titanosaurs ) or would have hindered rearing. For example, titanosaurs had an unusually flexible backbone, which would have decreased stability in a tripodal posture and would have put more strain on the muscles. Likewise, it is unlikely that brachiosaurids could rear up onto the hind legs, as their center of gravity was much farther forward than other sauropods, which would cause such

4824-433: The young reached adulthood. A 2014 study suggested that the time from laying the egg to the time of the hatching was likely to have been between 65 and 82 days. Exactly how segregated versus age-mixed herding varied across different groups of sauropods is unknown. Further examples of gregarious behavior will need to be discovered from more sauropod species to begin detecting possible patterns of distribution. Since early in

4896-603: Was coined by Othniel Charles Marsh in 1878, and is derived from Ancient Greek , meaning "lizard foot". Sauropods are one of the most recognizable groups of dinosaurs, and have become a fixture in popular culture due to their impressive size. Complete sauropod fossil finds are extremely rare. Many species, especially the largest, are known only from isolated and disarticulated bones. Many near-complete specimens lack heads, tail tips and limbs. Sauropods were herbivorous (plant-eating), usually quite long-necked quadrupeds (four-legged), often with spatulate (spatula-shaped: broad at

4968-532: Was found in Portugal. [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] Sauropod Sauropoda ( / s ɔː ˈ r ɒ p ə d ə / ), whose members are known as sauropods ( / ˈ s ɔːr ə p ɒ d z / ; from sauro- + -pod , ' lizard -footed'), is a clade of saurischian ('lizard-hipped') dinosaurs . Sauropods had very long necks, long tails, small heads (relative to

5040-570: Was named by Edward Drinker Cope in 1877. Its type genus is Camarasaurus , and it is defined as the clade containing all species more closely related to Camarasaurus supremus than Saltasaurus loricatus . Camarasauridae is typically regarded as belonging to Macronaria , one of the two major branches of Neosauropoda . Within Macronaria, it occupies a basal position, outside of Titanosauriformes . However, some studies have found Camarasauridae to lie outside Neosauropoda. Camarasaurus

5112-892: Was recognized early in the study of these animals, and, in fact, at least one sauropod specimen found in the 19th century ( Ornithopsis ) was originally misidentified as a pterosaur (a flying reptile) because of this. Some sauropods had armor . There were genera with small clubs on their tails, a prominent example being Shunosaurus , and several titanosaurs , such as Saltasaurus and Ampelosaurus , had small bony osteoderms covering portions of their bodies. A study by Michael D'Emic and his colleagues from Stony Brook University found that sauropods evolved high tooth replacement rates to keep up with their large appetites. The study suggested that Nigersaurus , for example, replaced each tooth every 14 days, Camarasaurus replaced each tooth every 62 days, and Diplodocus replaced each tooth once every 35 days. The scientists found qualities of

5184-442: Was the longest sauropod known from reasonably complete remains, but others, like the old record holder, Diplodocus , were also extremely long. The holotype (and now lost) vertebra of Amphicoelias fragillimus (now Maraapunisaurus ) may have come from an animal 58 metres (190 ft) long; its vertebral column would have been substantially longer than that of the blue whale. However, research published in 2015 speculated that

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