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104-1265: Coordinates : 4°18′N 35°48′E / 4.3°N 35.8°E / 4.3; 35.8 Geological formation in Kenya Lapurr Sandstone Stratigraphic range : Campanian - Paleocene ~ 72–65 Ma PreꞒ Ꞓ O S D C P T J K Pg N Type Geological formation Underlies Oligocene basalt Overlies Precambrian metamorphic basement Thickness 400–610 m (1,310–2,000 ft) Lithology Primary Sandstone Location Coordinates 4°18′N 35°48′E / 4.3°N 35.8°E / 4.3; 35.8 Approximate paleocoordinates 13°48′S 27°48′E / 13.8°S 27.8°E / -13.8; 27.8 Region Rift Valley Province Country [REDACTED] Kenya Extent Turkana Basin , Great Rift Valley, Kenya Type section Named for Lake Turkana [REDACTED] [REDACTED] Lapurr Sandstone (Kenya) The Lapurr Sandstone , also spelled Lapur Sandstone , previously considered part of
208-573: A carcharodontosaurid similar to Acrocanthosaurus and a dentary from Baryonyx or Suchomimus . The analysis was rejected in at least one subsequent paper. NMC 50791, held by the Canadian Museum of Nature , is a mid-cervical vertebra which is 19.5 centimeters (7.7 in) long from the Kem Kem Beds of Morocco . It is the holotype of Spinosaurus maroccanus, as described by Russell in 1996. Other specimens referred to S. maroccanus in
312-532: A prime meridian at the westernmost known land, designated the Fortunate Isles , off the coast of western Africa around the Canary or Cape Verde Islands , and measured north or south of the island of Rhodes off Asia Minor . Ptolemy credited him with the full adoption of longitude and latitude, rather than measuring latitude in terms of the length of the midsummer day. Ptolemy's 2nd-century Geography used
416-475: A sail-like structure , although some authors have suggested that the spines were covered in fat and formed a hump. The hip bones of Spinosaurus were reduced, and the legs were very short in proportion to the body. Its long and narrow tail was deepened by tall, thin neural spines and elongated chevrons , forming a flexible fin or paddle-like structure. Spinosaurus is known to have eaten fish and small to medium terrestrial prey as well. Evidence suggests that it
520-466: A 2007 paper using scaling based on skull length, challenged previous estimates of the size of Spinosaurus , finding the length too great and the weight too small. Based on estimated skull lengths of 1.5 to 1.75 m (4 ft 11 in to 5 ft 9 in), their estimates include a body length of 12.6 to 14.3 m (41 to 47 ft) and a body mass of 12 to 20.9 t (13.2 to 23.0 short tons). The lower estimates for Spinosaurus would imply that
624-544: A 2020 study on variation within Spinosaurus considers these differences in morphology to be indicative of variation in skull morphology within a single species, as is the case in Allosaurus. Some scientists have considered the genus Sigilmassasaurus a junior synonym of Spinosaurus . In Ibrahim and colleagues (2014), the specimens of Sigilmassasaurus was referred to Spinosaurus aegyptiacus together with "Spinosaurus B" as
728-513: A condition not observed in MSNM V4047 which has been referred to as a specimen of Spinosaurus , and thus adding a new possible diagnostic feature of Oxalaia . They also suggested that the premaxilla of Oxalaia is wider in the posterior portion than that of MSNM V4047, and that the lateral morphology of its rostrum was distinguished from other spinosaurines based on their morphometric analysis. In 2023, Isasmendi and colleagues considered Oxalaia as
832-467: A cooling wind, the animal would quite effectively cool itself in the warm climate of Cretaceous Africa. However, Bailey (1997) was of the opinion that a sail could have absorbed more heat than it radiated. Bailey proposed instead that Spinosaurus and other dinosaurs with long neural spines had fatty humps on their backs for energy storage, insulation, and shielding from heat. Many elaborate body structures of modern-day animals serve to attract members of
936-498: A distinct genus, though a very close relative of Spinosaurus , the two unified in the tribe Spinosaurini, coined in the study. The 2020 study indicates synonymy between Spinosaurus and Sigilmassasaurus , and considered specimens previously referred to Sigilmassasaurus as those of Spinosaurus . For instance, the referral of an isolated quadrate (specimen MHNM.KK376) to Sigilmassasaurus brevicollis , based on its difference from other specimens assigned to Spinosaurus aegyptiacus ,
1040-468: A dorsal neural arch (SAM 128), belonged to S. maroccanus . Although it was originally ascribed to S. maroccanus , based on their examination of this cranial material, the 2016 study considered the difference between the two species to be not taxonomically significant and either ontogenetic or intraspecific, and thus tentatively assigned the specimen to S. aegyptiacus . The 2017 study considered MNHN SAM 124 to belong to same taxon as MSNM V4047. BM231 (in
1144-407: A hydrodynamic fulcrum and hydrodynamically stabilizing the trunk along the dorsoventral axis, Spinosaurus ’ sail would also have compensated for the inertia of the lateral neck by tail movements and vice versa not only for predation but also for accelerated swimming. This behavior might also have been one reason for Spinosaurus ’ muscular chest and neck reported by Ibrahim and colleagues (2014). It
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#17328594753801248-646: A little before 1300; the text was translated into Latin at Florence by Jacopo d'Angelo around 1407. In 1884, the United States hosted the International Meridian Conference , attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich , England as the zero-reference line. The Dominican Republic voted against
1352-416: A location often facetiously called Null Island . In order to use the theoretical definitions of latitude, longitude, and height to precisely measure actual locations on the physical earth, a geodetic datum must be used. A horizonal datum is used to precisely measure latitude and longitude, while a vertical datum is used to measure elevation or altitude. Both types of datum bind a mathematical model of
1456-535: A longitudinal degree is 111.3 km. At 30° a longitudinal second is 26.76 m, at Greenwich (51°28′38″N) 19.22 m, and at 60° it is 15.42 m. On the WGS 84 spheroid, the length in meters of a degree of latitude at latitude ϕ (that is, the number of meters you would have to travel along a north–south line to move 1 degree in latitude, when at latitude ϕ ), is about The returned measure of meters per degree latitude varies continuously with latitude. Similarly,
1560-486: A maximum body length of 14 m (46 ft) and a maximum body mass of 7.4 t (8.2 short tons) by constructing a CT-based 3D skeletal model "with the axial column in neutral pose." They argued that the 2D graphical reconstruction of the aquatic hypothesis by Ibrahim and his colleagues in 2020 overestimated the presacral column length by 10%, ribcage depth by 25%, and forelimb length by 30% over dimensions based on CT-scanned fossils; these proportional overestimates shift
1664-670: A national cartographical organization include the North American Datum , the European ED50 , and the British OSGB36 . Given a location, the datum provides the latitude ϕ {\displaystyle \phi } and longitude λ {\displaystyle \lambda } . In the United Kingdom there are three common latitude, longitude, and height systems in use. WGS 84 differs at Greenwich from
1768-453: A shoal of fish or squid, sailfish also raise their sails to make themselves appear larger. When they slash or wipe their bills through shoaling fish by turning their heads, their dorsal sail and fins are outstretched to stabilize their bodies hydrodynamically (Lauder & Drucker, 2004). Domenici and colleagues (2014) postulate that these fin extensions enhance the accuracy of tapping and slashing. The sail can reduce yaw rotation by counteracting
1872-411: A significantly smaller pelvis (hip bone) than that of other giant theropods, with the surface area of the ilium (main body of the pelvis) half that of most members of the clade. The hind limbs were short, at just over 25 percent of the total body length, with the tibia (calf bone) being longer than the femur (thigh bone). Unlike in other theropods, the hallux (or fourth toe) of Spinosaurus touched
1976-841: A simple translation may be sufficient. Datums may be global, meaning that they represent the whole Earth, or they may be local, meaning that they represent an ellipsoid best-fit to only a portion of the Earth. Examples of global datums include World Geodetic System (WGS 84, also known as EPSG:4326 ), the default datum used for the Global Positioning System , and the International Terrestrial Reference System and Frame (ITRF), used for estimating continental drift and crustal deformation . The distance to Earth's center can be used both for very deep positions and for positions in space. Local datums chosen by
2080-401: A space on the inside of the snout, the authors speculated that Spinosaurus had pressure receptors inside the space that allowed it to hold its snout at the surface of the water to detect swimming prey species without seeing them. A 2013 study by Andrew R. Cuff and Emily J. Rayfield concluded that bio-mechanical data suggests that Spinosaurus was not an obligate piscivore and that its diet
2184-514: A specimen of Spinosaurus . As a spinosaurid, Spinosaurus would have had a long, muscular neck, curved in a sigmoid , or S-shape. Its shoulders were prominent, and the forelimbs large and stocky, bearing three clawed digits on each hand. The first finger (or "thumb") would have been the largest. Spinosaurus had long phalanges (finger bones), and only somewhat recurved claws , suggesting that its hands were longer compared to those of other spinosaurids. Very tall neural spines growing on
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#17328594753802288-489: A valid taxon based on the examination of its referred maxilla (MN 6119-V) which suggests that the position of its external naris would have been more anteriorly located, a condition similar to that of Irritator and baryonychines , differing from African spinosaurines including Spinosaurus aegyptiacus . Since its discovery, Spinosaurus has been a contender for the largest theropod dinosaur. Both Friedrich von Huene in 1926 and Donald F. Glut in 1982 listed it as among
2392-431: A wider distribution and supports the faunal exchange between South America and Africa during this time. However, subsequent studies have rejected the synonymy of Oxalaia with Spinosaurus aegyptiacus based on diagnostic features of the holotype (MN 6117-V) and the referred specimen (MN 6119-V). In 2021, Lacerda, Grillo and Romano noted that the anteromedial processes of the holotype maxillae (MN 6117-V) contact medially,
2496-500: A year, or 10 m in a century. A weather system high-pressure area can cause a sinking of 5 mm . Scandinavia is rising by 1 cm a year as a result of the melting of the ice sheets of the last ice age , but neighboring Scotland is rising by only 0.2 cm . These changes are insignificant if a local datum is used, but are statistically significant if a global datum is used. On the GRS 80 or WGS 84 spheroid at sea level at
2600-583: Is where Earth's equatorial radius a {\displaystyle a} equals 6,378,137 m and tan β = b a tan ϕ {\displaystyle \textstyle {\tan \beta ={\frac {b}{a}}\tan \phi }\,\!} ; for the GRS 80 and WGS 84 spheroids, b a = 0.99664719 {\textstyle {\tfrac {b}{a}}=0.99664719} . ( β {\displaystyle \textstyle {\beta }\,\!}
2704-585: Is a genus of spinosaurid dinosaur that lived in what now is North Africa during the Cenomanian stage of the Late Cretaceous period , about 100 to 94 million years ago . The genus was known first from Egyptian remains discovered in 1912 and described by German palaeontologist Ernst Stromer in 1915 . The original remains were destroyed in World War II , but additional material came to light in
2808-418: Is a spherical or geodetic coordinate system for measuring and communicating positions directly on Earth as latitude and longitude . It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system , the geographic coordinate system
2912-480: Is a snout (consisting of partial premaxillae, partial maxillae, vomers , and a dentary fragment). Described by Taquet and Russell in 1998, the specimen is 13.4 to 13.6 centimeters (5.3–5.4 in) in width; no length was stated. The specimen was located in Algeria, and "is of Albian age." Taquet and Russell believed that the specimen, along with a premaxilla fragment (SAM 125), two cervical vertebrae (SAM 126–127), and
3016-794: Is known as the reduced (or parametric) latitude ). Aside from rounding, this is the exact distance along a parallel of latitude; getting the distance along the shortest route will be more work, but those two distances are always within 0.6 m of each other if the two points are one degree of longitude apart. Like any series of multiple-digit numbers, latitude-longitude pairs can be challenging to communicate and remember. Therefore, alternative schemes have been developed for encoding GCS coordinates into alphanumeric strings or words: These are not distinct coordinate systems, only alternative methods for expressing latitude and longitude measurements. Spinosaurus Spinosaurus ( / ˌ s p aɪ n ə ˈ s ɔːr ə s / ; lit. ' spine lizard ' )
3120-540: Is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid ), as different datums will yield different latitude and longitude values for the same location. The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene , who composed his now-lost Geography at
3224-616: Is stored in the Natural History Museum, London . FSAC-KK 11888 is a partial subadult skeleton recovered from the Kem Kem beds of North Africa. It was described by Ibrahim and colleagues in 2014 and designated as the neotype specimen, though Evers and colleagues rejected the neotype designation for FSAC-KK-11888 in 2015. It includes cervical vertebrae, dorsal vertebrae, neural spines, a complete sacrum, femora, tibiae, pedal phalanges, caudal vertebra, several dorsal ribs, and fragments of
Lapurr Sandstone - Misplaced Pages Continue
3328-731: Is the angle east or west of a reference meridian to another meridian that passes through that point. All meridians are halves of great ellipses (often called great circles ), which converge at the North and South Poles. The meridian of the British Royal Observatory in Greenwich , in southeast London, England, is the international prime meridian , although some organizations—such as the French Institut national de l'information géographique et forestière —continue to use other meridians for internal purposes. The prime meridian determines
3432-405: Is ultimately calculated from latitude and longitude, it is crucial that they clearly state the datum on which they are based. For example, a UTM coordinate based on WGS84 will be different than a UTM coordinate based on NAD27 for the same location. Converting coordinates from one datum to another requires a datum transformation such as a Helmert transformation , although in certain situations
3536-410: Is unclear whether Spinosaurus was primarily a terrestrial predator or a piscivore , as indicated by its elongated jaws, conical teeth and raised nostrils. The hypothesis of spinosaurs as specialized fish eaters has been suggested before by A. J. Charig and A. C. Milner for Baryonyx . They base this on the anatomical similarity with crocodilians and the presence of digestive acid-etched fish scales in
3640-507: The Kem Kem Group suggested the Brazilian spinosaurine Oxalaia to be a potential junior synonym of Spinosaurus aegyptiacus . This was based on looking at the specimens assigned to Oxalaia , and the supposed autapomorphies of this taxon to be insignificant and fall within the hypodigm of Spinosaurus aegyptiacus . If supported by future studies, this would imply Spinosaurus aegyptiacus had
3744-796: The Kem Kem beds in Morocco and Oxalaia from the Alcântara Formation in Brazil , though other researchers propose both genera to be distinct taxa . Spinosaurus is the longest known terrestrial carnivore ; other large carnivores comparable to Spinosaurus include theropods such as Tyrannosaurus , Giganotosaurus and Carcharodontosaurus . The most recent study suggests that previous body size estimates are overestimated, and that S. aegyptiacus reached 14 m (46 ft) in length and 7.4 t (8.2 short tons) in body mass. The skull of Spinosaurus
3848-489: The Library of Alexandria in the 3rd century BC. A century later, Hipparchus of Nicaea improved on this system by determining latitude from stellar measurements rather than solar altitude and determining longitude by timings of lunar eclipses , rather than dead reckoning . In the 1st or 2nd century, Marinus of Tyre compiled an extensive gazetteer and mathematically plotted world map using coordinates measured east from
3952-505: The Museo di Storia Naturale di Milano ), described by Dal Sasso and colleagues in 2005 as Spinosaurus cf. S. aegyptiacus , consists of a snout (premaxillae, partial maxillae, and partial nasals) 98.8 centimeters (38.9 in) long from the Kem Kem Beds. An isolated fish vertebra, tentatively referred to Onchopristis , has been associated with the tooth alveolus of this specimen. Similarly,
4056-402: The Spinosaurus holotype specimen BSP 1912 VIII 19 discovered in the archives in 2000. On the basis of a photograph of the lower jaw and a photograph of the entire specimen as mounted, Smith concluded that Stromer's original 1915 drawings were slightly inaccurate. In 2003, Oliver Rauhut suggested that Stromer's Spinosaurus holotype was a chimera , composed of vertebrae and neural spines from
4160-695: The University of Chicago Paleontological Collection consists mainly of two narrow connected nasals with a fluted (ridged) crest from the region between the eyes. The specimen, which is 18.0 centimeters (7.1 in) long, was located in an early Cenomanian part of the Moroccan Kem Kem Beds in 1996 and described in the scientific literature in 2005 by Cristiano Dal Sasso of the Civic Natural History Museum in Milan and colleagues. MSNM V4047 (in
4264-421: The neotype and Spinosaurus maroccanus was considered as a nomen dubium following the conclusions of the other papers. A 2015 re-description of Sigilmassasaurus disputed these conclusions, and considered the genus valid, with inclusion of S. maroccanus as a synonym of Sigilmassasaurus instead. This conclusion was further supported in 2018 by Arden and colleagues, who consider Sigilmassasaurus to be
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4368-545: The Cenomanian age. Additionally, in 2024, a complete posterior cervical vertebra (specimen NHMUK PV R 38358) was assigned to Sigilmassasaurus brevicollis . Since the National Museum of Brazil fire in 2018 engulfed the palace housing the museum, with specimens of Oxalaia possibly being destroyed, any classification should remain tentative. In a 2020 paper written by Symth et al. in assessing spinosaurine specimens from
4472-581: The Cretaceous? Lapur and Muruanachok sandstones (Turkana Grits), Turkana Basin, Kenya" . Geological Magazine . 156 (8): 1334–1356. Bibcode : 2019GeoM..156.1334A . doi : 10.1017/S0016756818000663 . ISSN 0016-7568 . S2CID 134925592 . ^ Wescott, W.A.; Morley, C.K.; Karanja, F.M. (May 1993). "Geology of the "Turkana Grits" in the Lariu range and Mt. Porr areas, southern Lake Turkana, Northwestern Kenya". Journal of African Earth Sciences (and
4576-502: The Equator, one latitudinal second measures 30.715 m , one latitudinal minute is 1843 m and one latitudinal degree is 110.6 km. The circles of longitude, meridians, meet at the geographical poles, with the west–east width of a second naturally decreasing as latitude increases. On the Equator at sea level, one longitudinal second measures 30.92 m, a longitudinal minute is 1855 m and
4680-458: The Kem Kem region of southeastern Morocco, provided by François Escuillié and are deposited in the collections of the Muséum d’Histoire Naturelle of Marrakech. Only MHNM.KK376 is assigned to Sigilmassasaurus brevicollis , while the other five specimens are assigned to S. aegyptiacus , since the quadrates show two different morphologies, suggesting the existence of two spinosaurines in Morocco. However,
4784-569: The Middle East) . 16 (4): 425–435. Bibcode : 1993JAfES..16..425W . doi : 10.1016/0899-5362(93)90101-U . ^ Weishampel, et al. (2004). "Dinosaur distribution" Pp. 517-607. in Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. ISBN 0-520-24209-2 . " Pp. 517-607. ^ "OhioLINK ETD: Gorscak, Eric" . etd.ohiolink.edu . Archived from
4888-411: The advantage of more expeditions and material, it appears that they pertain either to Carcharodontosaurus or to Sigilmassasaurus . S. maroccanus was originally described by Dale Russell in 1996 as a new species based on the length of its neck vertebrae. Specifically, Russell claimed that the ratio of the length of the centrum (body of vertebra) to the height of the posterior articular facet
4992-687: The animal was shorter and lighter than Carcharodontosaurus and Giganotosaurus . The Therrien and Henderson study has been criticized for the choice of theropods used for comparison (e.g., most of the theropods used to set the initial equations were tyrannosaurids and carnosaurs , which have a different build than spinosaurids), and for the assumption that the Spinosaurus skull could be as little as 1.5 m (4 ft 11 in) in length. In 2014, Ibrahim and his colleagues suggested that Spinosaurus aegyptiacus could reach over 15 m (49 ft) in length. In 2022, however, Paul Sereno and his colleagues suggested that Spinosaurus aegyptiacus reached
5096-438: The back vertebrae of Spinosaurus formed the basis of what is usually called the animal's " sail ". The lengths of the neural spines reached over 10 times the diameters of the centra (vertebral bodies) from which they extended. The neural spines were slightly longer front to back at the base than higher up, and were unlike the thin rods seen in the pelycosaur finbacks Edaphosaurus and Dimetrodon , contrasting also with
5200-480: The center of mass anteriorly when translated to a flesh model, and thus the estimate from Ibrahim and his colleagues cannot be considered a reliable body size estimate. Its skull had a narrow snout filled with straight conical teeth that lacked serrations. There were six or seven teeth on each side of the very front of the upper jaw, in the premaxillae , and another twelve in both maxillae behind them. The second and third teeth on each side were noticeably larger than
5304-527: The collection of the Office National des Mines, Tunis) was described by Buffetaut and Ouaja in 2002. It consists of a partial anterior dentary 11.5 centimeters (4.5 in) in length from an early Albian stratum of the Chenini Formation of Tunisia . The dentary fragment, which included four alveoli and two partial teeth, was "extremely similar" to existing material of S. aegyptiacus . UCPC-2 in
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#17328594753805408-594: The complementary clade of all taxa closer to Baryonyx walkeri than to Spinosaurus aegyptiacus . Examinations by Marcos Sales, Cesar Schultz, and colleagues (2017) indicate that the South American spinosaurids Angaturama , Irritator , and Oxalaia were intermediate between Baronychinae and Spinosaurinae based on their craniodental features and cladistic analysis. This indicates that Baryonychinae may in fact be non-monophyletic. Their cladogram can be seen below. Baryonyx [REDACTED] The cladogram below depicts
5512-883: The condition observed in some other spinosaurids, though to a more extreme degree. Coupled with the also elongated chevron bones on the underside of the caudals, this resulted in a deep and narrow tail with a paddle or fin-like shape, comparable to the tails of newts and crocodilians . Spinosaurus gives its name to the dinosaur family Spinosauridae , which includes two subfamilies: Baryonychinae and Spinosaurinae. Baryonychinae includes Baryonyx from southern England and Suchomimus from Niger in central Africa . Spinosaurinae includes Spinosaurus , Siamosaurus , Ichthyovenator , Irritator , Angaturama (which may be synonymous with Irritator ), Sigilmassasaurus and Oxalaia (both of which may be synonymous with Spinosaurus ). The spinosaurines share unserrated straight teeth that are widely spaced (e.g., 12 on one side of
5616-527: The dentary fragment of Spinosaurus aegyptiacus , MPDM 31, is associated with the rostral tooth of Onchopristis . Like UCPC-2, it is thought to have come from the early Cenomanian. Arden and colleagues in 2018 tentatively assigned this specimen to Sigilmassasaurus brevicollis given its size. However, this assignment was later rejected by other researchers who considered the uniqueness of this specimen to be based on misinterpretations and poor preservation of another specimen, NHMUK R16665, another snout stored that
5720-761: The disputed Spinosaurus maroccanus (meaning "Moroccan spine lizard"). The first described remains of Spinosaurus were found and described in the early 20th century. In 1912, Richard Markgraf discovered a partial skeleton of a giant theropod dinosaur in the Bahariya Formation of western Egypt. In 1915, German paleontologist Ernst Stromer published an article assigning the specimen to a new genus and species, Spinosaurus aegyptiacus . Fragmentary additional remains from Bahariya, including vertebrae and hindlimb bones, were designated by Stromer as " Spinosaurus B " in 1934. Stromer considered them different enough to belong to another species, and this has been borne out. With
5824-422: The dorsal neural spines formed a shape that was roughly rectangular, similar in shape to the dorsal fins of sailfish. They therefore argue that Spinosaurus used its dorsal neural sail in the same manner as sailfish, and that it also employed its long narrow tail to stun prey like a modern thresher shark . Sailfish employ their dorsal fins for herding schools of fish into a " bait ball " where they cooperate to trap
5928-436: The early 21st century. It is unclear whether one or two species are represented in the fossils reported in the scientific literature. The type species is S. aegyptiacus from Egypt and Morocco . Although a potential second dubious species, S. maroccanus , has been recovered from Morocco, this dubious species is likely a junior synonym of S. aegyptiacus . Other possible junior synonyms include Sigilmassasaurus from
6032-570: The fact that the median tubercle and median suture is present in BSPG 2011 I 115 but absent in FSAC-KK-18122, so the presence or absence of such feature should not be used to taxonomically separate isolated spinosaurid remains. Regardless of the synonymy of Sigilmassasaurus with Spinosaurus , some authors consider the possibility that there could be a second distinct spinosaurid in North Africa during
6136-460: The far western Aleutian Islands . The combination of these two components specifies the position of any location on the surface of Earth, without consideration of altitude or depth. The visual grid on a map formed by lines of latitude and longitude is known as a graticule . The origin/zero point of this system is located in the Gulf of Guinea about 625 km (390 mi) south of Tema , Ghana ,
6240-486: The findings of Arden and colleagues (2018): Praia das Aguncheiras taxon Baryonyx walkeri [REDACTED] Eumeralla taxon Gara Samani taxon The function of the dinosaur's sail or hump is uncertain; scientists have proposed several hypotheses including heat regulation and display. In addition, such a prominent feature on its back could make it appear even larger than it was, intimidating other animals. The structure may have been used for thermoregulation . If
6344-405: The fish into a certain area where the sailfish can snatch the fish with their bills. The sail could have possibly reduced yaw rotation by counteracting the lateral force in the direction opposite to the slash as suggested by Gimsa and colleagues (2015). Spinosaurus anatomy exhibits another feature that may have a modern analogy: its long tail resembled that of the thresher shark, employed to slap
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#17328594753806448-418: The former too. In 2022, Sakamoto estimated that Spinosaurus had an anterior bite force of 4,829 newtons and a posterior bite force of 11,936 newtons. Based on this estimate, he asserted that the jaws of Spinosaurus are adapted for generating relatively faster shutting speeds with less muscle input force, indicating that the animal likely killed its prey with fast-snapping jaws rather than slow-crushing bites,
6552-475: The generic level. Six main partial specimens of Spinosaurus have been described. BSP 1912 VIII 19, described by Stromer in 1915 from the Bahariya Formation, was the holotype . The material consisted of the following items, most of which were incomplete: right and left dentaries and splenials from the lower jaw measuring 75 centimeters (30 in) long; a straight piece of the left maxilla that
6656-426: The ground, and the phalanges of the toe bones were unusually long and well-built. At their ends were shallow claws that had flat bottoms. This type of foot morphology is also seen in shorebirds , indicating that Spinosaurus 's feet evolved for walking across unstable substrate and that they may have been webbed . From the caudal vertebrae of the tail projected significantly elongated, thin neural spines, akin to
6760-1769: The informal "Turkana Grits" , is a geological formation in Kenya ( Turkana County ). It is the oldest unit in the Turkana Basin . The strata date back to the Late Cretaceous , likely Campanian to Maastrichtian , based on palynology and the presence of dyrosaurs and mosasaurs , the upper part of the unit likely extends into the Palaeogene, based on zircon dating. It predominantly consists of fine-coarse arkosic sandstone , which has been interpreted as either been deposited in fluvial or shallow marine conditions. Dinosaur remains among other vertebrates have been recovered from it around Lokitaung Gorge, though these mostly consist of heavily abraded, isolated bones of robust morphology like sauropod limb bones and caudal vertebrae. Vertebrate paleofauna [ edit ] Dinosaurs Taxa Presence Notes Images Lithostrotia gen. et sp. nov. Rift Valley Province , Kenya An unnamed titanosaur Spinosaurus sp.? (probably Theropoda indet.) Rift Valley Province, Kenya Sauropoda indet Two distinct taxa Iguanodontia indet Two distinct taxa ? Ornithopoda indet. Rift Valley Province, Kenya Abelisauridae gen. et sp. nov. Rift Valley Province, Kenya An unnamed giant abelisaurid, known from partial cranial and post cranial remains Theropoda indet. Large taxon Other reptiles Taxa Presence Notes Images Mosasauria indet Caudal vertebra, initially misidentified as
6864-404: The lateral force in the direction opposite to the slash. This means that prey is less likely to recognize the massive trunk as being part of an approaching predator (Marras and colleagues, 2015; Webb & Weihs 2015). Spinosaurus exhibited the anatomical features required to combine all three hunting strategies: a sail for herding prey more efficiently, as well as flexible tail and neck to slap
6968-1145: The latest Cretaceous of Northern Turkana, Kenya. Journal of Vertebrate Paleontology, SVP Program and Abstracts Book, 2013, pp211. ^ O'Connor PM, Sertich JJW, Manthi FK (2011) A pterodactyloid pterosaur from the Upper Cretaceous Lapurr sandstone, West Turkana, Kenya. Anais da Academia Brasileira de Ciências 83: 309–315. Retrieved from " https://en.wikipedia.org/w/index.php?title=Lapurr_Sandstone&oldid=1184305426 " Categories : Geologic formations of Kenya Upper Cretaceous Series of Africa Campanian Stage Maastrichtian Stage Cretaceous–Paleogene boundary Paleogene System of Africa Danian Stage Sandstone formations Fluvial deposits Paleontology in Kenya Hidden categories: Pages using gadget WikiMiniAtlas CS1 maint: others Articles with short description Short description matches Wikidata Coordinates on Wikidata Geographic coordinate system A geographic coordinate system ( GCS )
7072-415: The length in meters of a degree of longitude can be calculated as (Those coefficients can be improved, but as they stand the distance they give is correct within a centimeter.) The formulae both return units of meters per degree. An alternative method to estimate the length of a longitudinal degree at latitude ϕ {\displaystyle \phi } is to assume a spherical Earth (to get
7176-492: The maxilla), as opposed to the baryonychines, which have serrated curved teeth that are numerous (e.g., 30 on one side of the maxilla). An analysis of Spinosauridae by Arden and colleagues (2018) named the clade Spinosaurini and defined it as all spinosaurids closer to Spinosaurus aegyptiacus than to Irritator challengeri or Oxalaia quilombensis ; it also found Siamosaurus suteethorni and Icthyovenator laosensis to be members of Spinosaurinae. The subfamily Spinosaurinae
7280-489: The most massive theropods in their surveys, at 15 m (49 ft) in length and upwards of 6 t (6.6 short tons) in weight. In 1988, Gregory S. Paul also listed it as the longest theropod at 15 m (49 ft), but gave a lower mass estimate of 4 t (4.4 short tons). In 2005, Dal Sasso and colleagues assumed that Spinosaurus and the related Suchomimus had the same body proportions in relation to their skull lengths, and thereby calculated that Spinosaurus
7384-473: The motion, while France and Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911. The latitude ϕ of a point on Earth's surface is the angle between the equatorial plane and the straight line that passes through that point and through (or close to) the center of the Earth. Lines joining points of the same latitude trace circles on
7488-516: The one used on published maps OSGB36 by approximately 112 m. The military system ED50 , used by NATO , differs from about 120 m to 180 m. Points on the Earth's surface move relative to each other due to continental plate motion, subsidence, and diurnal Earth tidal movement caused by the Moon and the Sun. This daily movement can be as much as a meter. Continental movement can be up to 10 cm
7592-548: The opposite sex during mating. It is possible that the sail of Spinosaurus was used for courtship, in a way similar to a peacock 's tail. Stromer speculated that the size of the neural spines may have differed between males and females. Gimsa and colleagues (2015) suggest that the dorsal sail of Spinosaurus was analogous to the dorsal fins of sailfish and served a hydrodynamic purpose. Gimsa and others point out that more basal, long-legged spinosaurids had otherwise round or crescent-shaped dorsal sails, whereas in Spinosaurus ,
7696-409: The original on 2018-08-31. ^ The dinosauria . David B. Weishampel, Peter Dodson, Halszka Osmólska (2 ed.). Berkeley, Calif.: University of California Press. 2007. ISBN 978-0-520-25408-4 . OCLC 154697781 . {{ cite book }} : CS1 maint: others ( link ) ^ Sertich, J., O’Connor, P., Seiffert, E. & Manthi, F. 2013. A giant abelisaurid theropod from
7800-548: The postorbital part of the skull of MSNM V4047 had a shape similar to the postorbital part of the skull of Irritator , Dal Sasso and colleagues (2005) estimated that the skull of Spinosaurus was 1.75 meters (5.7 ft) long, but more recent estimates suggest a length of 1.6–1.68 meters (5.2–5.5 ft). The Dal Sasso and colleagues skull length estimate is questioned because skull shapes can vary across spinosaurid species and because MSNM V4047 may not belong to Spinosaurus itself, though recent studies have reconfirmed it as
7904-520: The proper Eastern and Western Hemispheres , although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E. This is not to be conflated with the International Date Line , which diverges from it in several places for political and convenience reasons, including between far eastern Russia and
8008-423: The relatively small ratio of surface area of their body compared to the overall volume ( Haldane's principle ), face far greater problems of dissipating excess heat at higher temperatures than gaining it at lower. Sails of large dinosaurs added considerably to the skin area of their bodies, with minimum increase of volume. Furthermore, if the sail was turned away from the sun, or positioned at a 90 degree angle towards
8112-403: The rest of the teeth in the premaxilla, creating a space between them and the large teeth in the front of the maxilla; large teeth in the lower jaw faced this space. The very tip of the snout holding those few large front teeth was expanded, and a small crest was present in front of the eyes. Using the dimensions of three specimens known as MSNM V4047, UCPC-2, and BSP 1912 VIII 19, and assuming that
8216-553: The rib cage of the type specimen . Large fish are known from the faunas containing other spinosaurids, including the Mawsonia , in the mid-Cretaceous of northern Africa and Brazil. Direct evidence for spinosaur diet comes from related European and South American taxa. Baryonyx was found with fish scales and bones from juvenile Iguanodon in its stomach, while a tooth embedded in a South American pterosaur bone suggests that spinosaurs occasionally preyed on pterosaurs, but Spinosaurus
8320-604: The sail of the Permian synapsid Dimetrodon , which lived before the dinosaurs even appeared, produced by convergent evolution . The structure may also have been more hump-like than sail-like, as noted by Stromer in 1915 ("one might rather think of the existence of a large hump of fat [ German : Fettbuckel ], to which the [neural spines] gave internal support") and by Jack Bowman Bailey in 1997. In support of his "buffalo-back" hypothesis, Bailey argued that in Spinosaurus , Ouranosaurus , and other dinosaurs with long neural spines,
8424-430: The same datum will obtain the same location measurement for the same physical location. However, two different datums will usually yield different location measurements for the same physical location, which may appear to differ by as much as several hundred meters; this not because the location has moved, but because the reference system used to measure it has shifted. Because any spatial reference system or map projection
8528-539: The same paper were two other mid-cervical vertebrae (NMC 41768 and NMC 50790), an anterior dentary fragment (NMC 50832), a mid-dentary fragment (NMC 50833), and an anterior dorsal neural arch (NMC 50813). Russell stated that "only general locality information could be provided" for the specimen, and therefore it could be dated only "possibly" to the Albian. MNHN SAM 124, housed at the Muséum National d'Histoire Naturelle ,
8632-646: The same prime meridian but measured latitude from the Equator instead. After their work was translated into Arabic in the 9th century, Al-Khwārizmī 's Book of the Description of the Earth corrected Marinus' and Ptolemy's errors regarding the length of the Mediterranean Sea , causing medieval Arabic cartography to use a prime meridian around 10° east of Ptolemy's line. Mathematical cartography resumed in Europe following Maximus Planudes ' recovery of Ptolemy's text
8736-486: The shape of the earth (usually a reference ellipsoid for a horizontal datum, and a more precise geoid for a vertical datum) to the earth. Traditionally, this binding was created by a network of control points , surveyed locations at which monuments are installed, and were only accurate for a region of the surface of the Earth. Some newer datums are bound to the center of mass of the Earth. This combination of mathematical model and physical binding mean that anyone using
8840-690: The skull. The body proportions of the specimen have been debated, as the hind limbs are disproportionately shorter in the specimen than in previous reconstructions. However, it has been demonstrated by multiple paleontologists that the specimen is not a chimera, and is indeed a specimen of Spinosaurus that suggests that the animal had much smaller hind limbs than previously thought. Other known specimens consist mainly of very fragmentary remains and scattered teeth. These include: MHNM.KK374, MHNM.KK375, MHNM.KK376, MHNM.KK377, MHNM.KK378 and MSNM V6896 are six isolated quadrates (skull bones) of different sizes that were collected by locals and acquired commercially in
8944-508: The species as valid without much comment, most researchers regard S. maroccanus as a nomen dubium (dubious name) or as a junior synonym of S. aegyptiacus . Some studies have referred the holotype and other referred specimens of S. maroccanus (NMC 50791 and MNHN SAM 124-128) as S. cf. aegyptiacus . The specimens previously ascribed as paratypes of S. maroccanus (NMC 41768 and NMC 50790) are reidentified as indeterminate spinosaurid specimens that are currently not identifiable at
9048-484: The spines were relatively shorter and thicker than the spines of pelycosaurs (which are known to have sails); instead, the dinosaurs' neural spines were similar to the neural spines of extinct hump-backed mammals such as Megacerops and Bison latifrons . In 2014, Ibrahim and colleagues instead posited that the spines were covered tightly by skin, similar to a crested chameleon , given their compactness, sharp edges, and likely poor blood flow . Spinosaurus had
9152-426: The structure contained abundant blood vessels, the animal could have used the sail's large surface area to absorb heat. This would imply that the animal was only partly warm-blooded at best and lived in climates where night-time temperatures were cool or low and the sky usually not cloudy. It is also possible that the structure was used to radiate excess heat from the body, rather than to collect it. Large animals, due to
9256-458: The surface of Earth called parallels , as they are parallel to the Equator and to each other. The North Pole is 90° N; the South Pole is 90° S. The 0° parallel of latitude is designated the Equator , the fundamental plane of all geographic coordinate systems. The Equator divides the globe into Northern and Southern Hemispheres . The longitude λ of a point on Earth's surface
9360-475: The thicker spines in the iguanodontian Ouranosaurus . Spinosaurus sails were unusual, although other dinosaurs, namely Ouranosaurus , which lived a few million years earlier in the same general region as Spinosaurus , and the Early Cretaceous South American sauropod Amargasaurus , might have developed similar structural adaptations of their vertebrae. The sail may be an analog of
9464-422: The vertebra of a pterosaur Dyrosauridae Abundant remains Testudines See also [ edit ] List of dinosaur-bearing rock formations References [ edit ] ^ Agyemang, Prince C. Owusu; Roberts, Eric M.; Downie, Bob; Sertich, Joseph J. W. (August 2019). "Sedimentary provenance and maximum depositional age analysis of
9568-539: The water for stunning, injuring or killing prey. The submerged dorsal sail would have provided a strong centreboard-like counterforce for powerful sidewards movements of the strong neck and long tail, as performed by sailfish (Domenici and colleagues, 2014) or thresher sharks (Oliver and colleagues, 2013). While smaller dorsal sails or fins make the dorsal water volume better accessible for slashing, it can be speculated that their smaller stabilization effect makes lateral slashing less efficient (e.g. for thresher sharks). Forming
9672-451: The water to herd and stun shoals of fish before devouring them (Oliver and colleagues, 2013). The strategies that sailfish and thresher sharks employ against shoaling fish are more effective when the shoal is first concentrated into a ‘bait ball’ (Helfman, Collette & Facey, 1997; Oliver and colleagues, 2013; Domenici and colleagues, 2014). Since this is difficult for individual predators to achieve, they cooperate in this effort. When herding
9776-445: The width per minute and second, divide by 60 and 3600, respectively): where Earth's average meridional radius M r {\displaystyle \textstyle {M_{r}}\,\!} is 6,367,449 m . Since the Earth is an oblate spheroid , not spherical, that result can be off by several tenths of a percent; a better approximation of a longitudinal degree at latitude ϕ {\displaystyle \phi }
9880-643: Was semiaquatic ; how capable it was of swimming has been strongly contested. Spinosaurus 's leg bones had osteosclerosis (high bone density), allowing for better buoyancy control. Multiple functions have been put forward for the dorsal sail, including thermoregulation and display ; either to intimidate rivals or attract mates. It lived in a humid environment of tidal flats and mangrove forests alongside many other dinosaurs, as well as fish, crocodylomorphs , lizards, turtles, pterosaurs , and plesiosaurs . Two species of Spinosaurus have been named: Spinosaurus aegyptiacus (meaning "Egyptian spine lizard") and
9984-431: Was 1.1 in S. aegyptiacus and 1.5 in S. maroccanus . Later authors have been split on this topic. Some authors note that the length of the vertebrae can vary from individual to individual, that the holotype specimen was destroyed and thus cannot be compared directly with the S. maroccanus specimen, and that it is unknown which cervical vertebrae the S. maroccanus specimens represent. Therefore, though some have retained
10088-533: Was 16 to 18 m (52 to 59 ft) in length and 7 to 9 t (7.7 to 9.9 short tons) in weight. The estimates were criticized because the skull length estimate was uncertain, and (assuming that body mass increases as the cube of body length) scaling Suchomimus, which was 11 m (36 ft) long and 3.8 t (4.2 short tons) in mass, to the range of estimated lengths of Spinosaurus would produce an estimated body mass of 11.7 to 16.7 t (12.9 to 18.4 short tons). François Therrien and Donald Henderson, in
10192-410: Was described but not drawn; 20 teeth; 2 cervical vertebrae; 7 dorsal (trunk) vertebrae; 3 sacral vertebrae; 1 caudal vertebra; 4 thoracic ribs; and gastralia . Of the nine neural spines whose heights are given, the longest ("i," associated with a dorsal vertebra) was 1.65 meters (5.4 ft) in length. Stromer claimed that the specimen was from the early Cenomanian, about 97 million years ago. It
10296-621: Was destroyed in World War II , specifically "during the night of 24/25 April 1944 in a British bombing raid of Munich" that severely damaged the building housing the Paläontologisches Museum München (Bavarian State Collection of Paleontology). However, detailed drawings and descriptions of the specimen remain. Stromer's son donated Stromer's archives to the Paläontologische Staatssammlung München in 1995, and Smith and colleagues analyzed two photographs of
10400-408: Was likely to have been a generalized and opportunistic predator, possibly a Cretaceous equivalent of large grizzly bears , being biased toward fishing, though it undoubtedly scavenged and took many kinds of small or medium-sized prey. In 2009, Dal Sasso and colleagues. reported the results of X-ray computed tomography of the MSNM V4047 snout. As the foramina on the outside all communicated with
10504-457: Was long, low, and narrow, similar to that of a modern crocodilian , and bore straight conical teeth with no serrations . It would have had large, robust forelimbs bearing three-fingered hands, with an enlarged claw on the first digit . The distinctive neural spines of Spinosaurus , which were long extensions of the vertebrae (or backbones), grew to at least 1.65 m (5.4 ft) long and were likely to have had skin connecting them, forming
10608-451: Was more closely associated with each individual's size. The characteristic rostral morphology of Spinosaurus allowed its jaws to resist bending in the vertical direction, but its jaws were poorly adapted with respect to resisting lateral bending compared to other members of this group ( Baryonyx ) and modern alligators. This suggests that Spinosaurus preyed more regularly on fish than it did on land animals, although considered predators of
10712-428: Was named by Sereno in 1998, and defined by Holtz and colleagues (2004) as all taxa closer to Spinosaurus aegyptiacus than to Baryonyx walkeri . The subfamily Baryonychinae was named by Charig & Milner in 1986. They erected both the subfamily and the family Baryonychidae for the newly discovered Baryonyx , before it was referred to Spinosauridae. Their subfamily was defined by Holtz and colleagues in 2004, as
10816-410: Was rejected by the 2020 study which noted that these differences in morphology are indicative of variation in skull morphology within a single species. The 2019 study assigned a juvenile specimen FSAC-KK-18122 to Sigilmassasaurus brevicollis based on its identical proportion to BSPG 2011 I 115 which was assigned to the taxon in a 2015 study, but this referral was also rejected in a 2020 study based on
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