Sauroposeidon
Encyclopedia
Sauroposeidon (ˌsɔrɵpɵˈsaɪdən ; meaning "earthquake
god
lizard
", after the Greek god Poseidon
) is a genus
of sauropod dinosaur
known from four neck vertebrae that were found in the southeastern portion of the US state of Oklahoma
. The fossil
s were found in rocks dating to the Early Cretaceous
, a period when the sauropods of North America had diminished in both size and numbers, making it the last known giant dinosaur on the continent. While the fossils were discovered in 1994, due to their unexpected age and unusual size they were initially misclassified as pieces of petrified wood
. A more detailed analysis in 1999 revealed their true nature which resulted in a minor media frenzy, and formal publication of the find the following year.
Paleoecological
analysis indicates that Sauroposeidon lived on the shores of the Gulf of Mexico
, in a river delta
. Like other brachiosaurids, Sauroposeidon was a quadruped
al herbivore
with longer forelimb
s than hindlimbs, a similar body design to the modern giraffe
. Extrapolations based on its more completely known relative Brachiosaurus
indicate that the head of Sauroposeidon could reach 17 m (55.8 ft) in height with its neck extended, making it the tallest known dinosaur. With an estimated length of up to 34 m (111.5 ft) and a mass of 50–60 MT (55.1–66.1 ST), it also ranks among the longest and heaviest.
The vertebrae were discovered in rural Oklahoma
, not far from the Texas
border, in a claystone
outcrop that dates the fossils to about 110 million years ago (mya). This falls within the Early Cretaceous Period, specificially between the Aptian
and Albian
epochs.
The four neck vertebrae were discovered in 1994 at the Antlers Formation
in Atoka County, Oklahoma
by Dr. Richard Cifelli and a team from the Oklahoma Museum of Natural History
. Initially the fossils were believed to be simply too large to be the remains of an animal, and due to the state of preservation, believed to be tree trunks. In fact, they are the longest such bones known in dinosaurs.
Thus, the vertebrae were stored until 1999, when Dr. Cifelli gave them to a graduate student, Matt Wedel, to analyze as part of a project. Upon their realization of the find's significance, they issued a press release in October 1999, followed by official publication of their findings in the Journal of Vertebrate Paleontology
in March 2000. The new species was dubbed S. proteles, and the holotype
is OMNH 53062.
for "lizard"), and Poseidon
, a sea
-god
in Greek mythology
, who is also associated with earthquake
s, that facet styled as Ennosigaios or Enosikhthōn, "Earthshaker". This is a reference to the notion that a sauropod's weight was so great that the ground shook as it walked.
The specific descriptor proteles also comes from the Ancient Greek and means "perfect before the end", which refers to Sauroposeidon's status as the last and most specialized giant sauropod known in North America, during the Early Cretaceous.
The press release in 1999 immediately garnered international media attention, which led to many (inaccurate) news reports of "the largest dinosaur ever!". While it is true that Sauroposeidon is probably the tallest known dinosaur, it is neither the longest nor the most massive. Argentinosaurus
is a better candidate for the title "World's Largest Dinosaur" (presuming to ignore, as is conventional, Amphicoelias
), though weak fossil
evidence makes an exact ranking impossible.
The Sauroposeidon find was composed of four articulated, mid-cervical
vertebrae (numbers 5 to 8), with the cervical rib
s in place. The vertebrae are extremely elongated, with the largest one having an overall length of 1.4 m (4.6 ft), making it the longest sauropod neck vertebra on record. Examination of the bone
s revealed that they are honeycombed with tiny air cells, and are very thin, like the bones of a chicken
or an ostrich
, making the neck lighter and easier to lift. The cervical ribs were remarkably long as well, with the longest measurable rib (on vertebra 6) measuring 3.42 m (11.2 ft) – about 18% longer than the longest rib reported for Giraffatitan, but exceeded in length by the cervical ribs of Mamenchisaurus
.
Estimates of Sauroposeidons size are based on a comparison between the four Sauroposeidon vertebrae and the vertebrae of the HM SII specimen of Giraffatitan
brancai, located in the Humboldt Museum
in Berlin
. The HM SII is the most complete brachiosaur known, though since it is composed of pieces from different individuals its proportions may not be totally accurate. Comparisons to the other brachiosaurid relatives of Sauroposeidon are difficult due to limited remains.
The neck length of Sauroposeidon is estimated at 11.25–12 m (36.9–39.4 ft), compared to a neck length of 9 m (29.5 ft) for the HM SII Giraffatitan. This is based on the assumption that the rest of the neck has the same proportions as Giraffatitan, which is a reasonably good conjecture.
Sauroposeidon was probably able to raise its head 17 m (55.8 ft) above the ground, which is as high as a six-story building. The long neck and the high brachiosaurid shoulders are what makes it the tallest known dinosaur. In some ways, its build is similar to the modern giraffe
, with a short body and an extremely long neck. In comparison, Giraffatitan
could probably raise its head 13.5 m (44.3 ft) into the air.
Sauroposeidon's shoulder height was probably 6–7 m (19.7–23 ft). Estimates of its total possible length have ranged from 28 m (91.9 ft) to 34 m (111.5 ft).
The mass of Sauroposeidon is estimated at 50–60 MT (55.1–66.1 ST). While the vertebrae of Sauroposeidon are 25–33% longer than Giraffatitan, they are only 10–15% larger in diameter. This means that while Sauroposeidon probably has a larger body than Giraffatitan its body is smaller in comparison to the size of its neck, so it did not weigh as much as a scaled-up Giraffatitan. By comparison, Giraffatitan might have weighed 36–40 MT (39.7–44.1 ST). This estimate of the Giraffatitan is an average of several different methodologies.
However, Sauroposeidon has a gracile neck compared to Giraffatitan. If the rest of the body turns out to be similarly slender, the mass estimate may be too high. This could be similar to the way the relatively robust Apatosaurus
weighs far more than the longer but much slimmer Diplodocus. In addition, it is possible that sauropods may have had an air sac system, like those in bird
s, which could reduce all sauropod mass estimates by 20% or more.
and soon spread across the world. By the time of the late Jurassic, North America and Africa
were dominated by the diplodocids and brachiosaurids and, by the end of the Late Cretaceous, titanosaurids were widespread (though only in the southern hemisphere). Between these periods, in the Early Cretaceous, the fossil record is sparse. Few specimens have been found in North America from that time and those specimens that do exist are often fragmentary or represent juvenile members of their species. Most of the surviving sauropods at the time were also shrinking in size to a mere 15 m (49.2 ft) in length, and maybe 10–15 MT (11–16.5 ST), which makes the discovery of an extremely specialized super-giant like Sauroposeidon very unusual.
Sauroposeidon lived on the shores of the Gulf of Mexico
, which ran through Oklahoma at that time, in a vast river delta
, similar to the Mississippi delta
today. There were probably no predators which could attempt to attack a full-grown Sauroposeidon, but juveniles were likely to be preyed on by the contemporary Acrocanthosaurus atokensis (a carnosaur
slightly smaller than a Tyrannosaurus
) and the small coelurosaur Deinonychus antirrhopus.
Xenoposeidon
, a giant brachiosaurid similar to Sauroposeidon was described in 2004, by Darren Naish
and colleagues, and is from the Early Cretaceous
period of England
. Known only from two neck vertebrae, it was apparently similar in some details to Sauroposeidon and perhaps similar in size. Its discovery highlights the similarity seen between Early Cretaceous North American and European dinosaurs.
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
god
God
God is the English name given to a singular being in theistic and deistic religions who is either the sole deity in monotheism, or a single deity in polytheism....
lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
", after the Greek god Poseidon
Poseidon
Poseidon was the god of the sea, and, as "Earth-Shaker," of the earthquakes in Greek mythology. The name of the sea-god Nethuns in Etruscan was adopted in Latin for Neptune in Roman mythology: both were sea gods analogous to Poseidon...
) is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of sauropod dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
known from four neck vertebrae that were found in the southeastern portion of the US state of Oklahoma
Oklahoma
Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...
. The fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s were found in rocks dating to the Early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
, a period when the sauropods of North America had diminished in both size and numbers, making it the last known giant dinosaur on the continent. While the fossils were discovered in 1994, due to their unexpected age and unusual size they were initially misclassified as pieces of petrified wood
Petrified wood
Petrified wood is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree having turned completely into stone by the process of permineralization...
. A more detailed analysis in 1999 revealed their true nature which resulted in a minor media frenzy, and formal publication of the find the following year.
Paleoecological
Paleoecology
Paleoecology uses data from fossils and subfossils to reconstruct the ecosystems of the past. It involves the study of fossil organisms and their associated remains, including their life cycle, living interactions, natural environment, and manner of death and burial to reconstruct the...
analysis indicates that Sauroposeidon lived on the shores of the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
, in a river delta
River delta
A delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
. Like other brachiosaurids, Sauroposeidon was a quadruped
Quadruped
Quadrupedalism is a form of land animal locomotion using four limbs or legs. An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet"...
al herbivore
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
with longer forelimb
Forelimb
A forelimb is an anterior limb on an animal's body. When referring to quadrupeds , the term foreleg is often instead used....
s than hindlimbs, a similar body design to the modern giraffe
Giraffe
The giraffe is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant...
. Extrapolations based on its more completely known relative Brachiosaurus
Brachiosaurus
Brachiosaurus is a genus of sauropod dinosaur from the Jurassic Morrison Formation of North America. It was first described by Elmer S. Riggs in 1903 from fossils found in the Grand River Canyon of western Colorado, in the United States. Riggs named the dinosaur Brachiosaurus altithorax,...
indicate that the head of Sauroposeidon could reach 17 m (55.8 ft) in height with its neck extended, making it the tallest known dinosaur. With an estimated length of up to 34 m (111.5 ft) and a mass of 50–60 MT (55.1–66.1 ST), it also ranks among the longest and heaviest.
Discovery
Oklahoma
Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...
, not far from the Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
border, in a claystone
Claystone
Claystone is a geological term used to describe a clastic sedimentary rock that is composed primarily of clay-sized particles ....
outcrop that dates the fossils to about 110 million years ago (mya). This falls within the Early Cretaceous Period, specificially between the Aptian
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...
and Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
epochs.
The four neck vertebrae were discovered in 1994 at the Antlers Formation
Antlers Formation
The Antlers Formation occurs as a band of strata from Arkansas through southern Oklahoma into northeastern Texas. It consists of 150 m of silty to sandy mudstones, fine- to coarse grained sandstones that are poorly to moderately sorted and cemented with clay or calcium carbonate...
in Atoka County, Oklahoma
Atoka County, Oklahoma
Atoka County is a county located in the U.S. state of Oklahoma, and was formed in 1907 from Choctaw Lands. As of 2000, the population is 13,879. Its county seat is Atoka.-Geography:...
by Dr. Richard Cifelli and a team from the Oklahoma Museum of Natural History
Sam Noble Oklahoma Museum of Natural History
The Sam Noble Oklahoma Museum of Natural History is a natural history museum in Norman, Oklahoma, operated by the University of Oklahoma. It is currently housed in a building on Chautauqua Avenue that opened on May 1, 2000. The museum's exhibits include a Native American gallery and collections of...
. Initially the fossils were believed to be simply too large to be the remains of an animal, and due to the state of preservation, believed to be tree trunks. In fact, they are the longest such bones known in dinosaurs.
Thus, the vertebrae were stored until 1999, when Dr. Cifelli gave them to a graduate student, Matt Wedel, to analyze as part of a project. Upon their realization of the find's significance, they issued a press release in October 1999, followed by official publication of their findings in the Journal of Vertebrate Paleontology
Journal of Vertebrate Paleontology
The Journal of Vertebrate Paleontology was founded in 1980 at the University of Oklahoma by Dr. Jiri Zidek. It is a scientific journal that publishes original contributions on all aspects of the vertebrate paleontology, including vertebrate origins, evolution, functional morphology, taxonomy,...
in March 2000. The new species was dubbed S. proteles, and the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
is OMNH 53062.
Etymology
The generic name comes from sauros (GreekAncient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
for "lizard"), and Poseidon
Poseidon
Poseidon was the god of the sea, and, as "Earth-Shaker," of the earthquakes in Greek mythology. The name of the sea-god Nethuns in Etruscan was adopted in Latin for Neptune in Roman mythology: both were sea gods analogous to Poseidon...
, a sea
Sea
A sea generally refers to a large body of salt water, but the term is used in other contexts as well. Most commonly, it means a large expanse of saline water connected with an ocean, and is commonly used as a synonym for ocean...
-god
Deity
A deity is a recognized preternatural or supernatural immortal being, who may be thought of as holy, divine, or sacred, held in high regard, and respected by believers....
in Greek mythology
Greek mythology
Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...
, who is also associated with earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s, that facet styled as Ennosigaios or Enosikhthōn, "Earthshaker". This is a reference to the notion that a sauropod's weight was so great that the ground shook as it walked.
The specific descriptor proteles also comes from the Ancient Greek and means "perfect before the end", which refers to Sauroposeidon's status as the last and most specialized giant sauropod known in North America, during the Early Cretaceous.
Size
Argentinosaurus
Argentinosaurus is a genus of titanosaur sauropod dinosaur first discovered by Guillermo Heredia in Argentina. The generic name refers to the country in which it was discovered...
is a better candidate for the title "World's Largest Dinosaur" (presuming to ignore, as is conventional, Amphicoelias
Amphicoelias
Amphicoelias is a genus of herbivorous sauropod dinosaur that includes what may be the largest dinosaur ever discovered, A. fragillimus. Based on surviving descriptions of a single fossil bone, A. fragillimus may have been the longest known vertebrate at in length, and may have had a mass of up...
), though weak fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
evidence makes an exact ranking impossible.
The Sauroposeidon find was composed of four articulated, mid-cervical
Cervical vertebrae
In vertebrates, cervical vertebrae are those vertebrae immediately inferior to the skull.Thoracic vertebrae in all mammalian species are defined as those vertebrae that also carry a pair of ribs, and lie caudal to the cervical vertebrae. Further caudally follow the lumbar vertebrae, which also...
vertebrae (numbers 5 to 8), with the cervical rib
Rib
In vertebrate anatomy, ribs are the long curved bones which form the rib cage. In most vertebrates, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the chest cavity. They serve to protect the lungs, heart, and other internal organs of the thorax...
s in place. The vertebrae are extremely elongated, with the largest one having an overall length of 1.4 m (4.6 ft), making it the longest sauropod neck vertebra on record. Examination of the bone
Bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
s revealed that they are honeycombed with tiny air cells, and are very thin, like the bones of a chicken
Chicken
The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird...
or an ostrich
Ostrich
The Ostrich is one or two species of large flightless birds native to Africa, the only living member of the genus Struthio. Some analyses indicate that the Somali Ostrich may be better considered a full species apart from the Common Ostrich, but most taxonomists consider it to be a...
, making the neck lighter and easier to lift. The cervical ribs were remarkably long as well, with the longest measurable rib (on vertebra 6) measuring 3.42 m (11.2 ft) – about 18% longer than the longest rib reported for Giraffatitan, but exceeded in length by the cervical ribs of Mamenchisaurus
Mamenchisaurus
Mamenchisaurus was a plant-eating four-legged dinosaur, known for its remarkably long neck which made up half its total length. It is known from numerous species which ranged in time from 160 to 145 million years ago, from the Oxfordian to Tithonian ages of the late Jurassic Period of...
.
Estimates of Sauroposeidons size are based on a comparison between the four Sauroposeidon vertebrae and the vertebrae of the HM SII specimen of Giraffatitan
Giraffatitan
Giraffatitan, meaning "giraffe titan", is a genus of sauropod dinosaur that lived during the late Jurassic Period . It was originally named as an African species of Brachiosaurus...
brancai, located in the Humboldt Museum
Humboldt Museum
The Museum für Naturkunde, officially the ' or Naturkundemuseum , occasionally known as the Humboldt Museum, is a natural history museum in Berlin, Germany. Usually the museum's name is abbreviated MFN...
in Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
. The HM SII is the most complete brachiosaur known, though since it is composed of pieces from different individuals its proportions may not be totally accurate. Comparisons to the other brachiosaurid relatives of Sauroposeidon are difficult due to limited remains.
The neck length of Sauroposeidon is estimated at 11.25–12 m (36.9–39.4 ft), compared to a neck length of 9 m (29.5 ft) for the HM SII Giraffatitan. This is based on the assumption that the rest of the neck has the same proportions as Giraffatitan, which is a reasonably good conjecture.
Sauroposeidon was probably able to raise its head 17 m (55.8 ft) above the ground, which is as high as a six-story building. The long neck and the high brachiosaurid shoulders are what makes it the tallest known dinosaur. In some ways, its build is similar to the modern giraffe
Giraffe
The giraffe is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant...
, with a short body and an extremely long neck. In comparison, Giraffatitan
Giraffatitan
Giraffatitan, meaning "giraffe titan", is a genus of sauropod dinosaur that lived during the late Jurassic Period . It was originally named as an African species of Brachiosaurus...
could probably raise its head 13.5 m (44.3 ft) into the air.
Sauroposeidon's shoulder height was probably 6–7 m (19.7–23 ft). Estimates of its total possible length have ranged from 28 m (91.9 ft) to 34 m (111.5 ft).
The mass of Sauroposeidon is estimated at 50–60 MT (55.1–66.1 ST). While the vertebrae of Sauroposeidon are 25–33% longer than Giraffatitan, they are only 10–15% larger in diameter. This means that while Sauroposeidon probably has a larger body than Giraffatitan its body is smaller in comparison to the size of its neck, so it did not weigh as much as a scaled-up Giraffatitan. By comparison, Giraffatitan might have weighed 36–40 MT (39.7–44.1 ST). This estimate of the Giraffatitan is an average of several different methodologies.
However, Sauroposeidon has a gracile neck compared to Giraffatitan. If the rest of the body turns out to be similarly slender, the mass estimate may be too high. This could be similar to the way the relatively robust Apatosaurus
Apatosaurus
Apatosaurus , also known by the popular but scientifically deprecated synonym Brontosaurus, is a genus of sauropod dinosaur that lived from about 154 to 150 million years ago, during the Jurassic Period . It was one of the largest land animals that ever existed, with an average length of and a...
weighs far more than the longer but much slimmer Diplodocus. In addition, it is possible that sauropods may have had an air sac system, like those in bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s, which could reduce all sauropod mass estimates by 20% or more.
Palaeoecology
Sauropods, which include the largest terrestrial animals of all time, were a very wide ranging and successful group. They first appeared in the Early JurassicJurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
and soon spread across the world. By the time of the late Jurassic, North America and Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
were dominated by the diplodocids and brachiosaurids and, by the end of the Late Cretaceous, titanosaurids were widespread (though only in the southern hemisphere). Between these periods, in the Early Cretaceous, the fossil record is sparse. Few specimens have been found in North America from that time and those specimens that do exist are often fragmentary or represent juvenile members of their species. Most of the surviving sauropods at the time were also shrinking in size to a mere 15 m (49.2 ft) in length, and maybe 10–15 MT (11–16.5 ST), which makes the discovery of an extremely specialized super-giant like Sauroposeidon very unusual.
Sauroposeidon lived on the shores of the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
, which ran through Oklahoma at that time, in a vast river delta
River delta
A delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
, similar to the Mississippi delta
Mississippi River Delta
The Mississippi River Delta is the modern area of land built up by alluvium deposited by the Mississippi River as it slows down and enters the Gulf of Mexico...
today. There were probably no predators which could attempt to attack a full-grown Sauroposeidon, but juveniles were likely to be preyed on by the contemporary Acrocanthosaurus atokensis (a carnosaur
Carnosauria
Carnosauria is a group of large predatory dinosaurs that lived during the Jurassic and Cretaceous periods. While it originally contained a wide assortment of giant theropods that were not closely related, the group has since been defined to encompass only the allosaurs and their closest kin...
slightly smaller than a Tyrannosaurus
Tyrannosaurus
Tyrannosaurus meaning "tyrant," and sauros meaning "lizard") is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex , commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other...
) and the small coelurosaur Deinonychus antirrhopus.
Xenoposeidon
Xenoposeidon
Xenoposeidon is a genus of sauropod dinosaur from the Early Cretaceous of England, living about 140 million years ago. It is known from a single partial vertebra with unusual features, unlike those of other sauropods...
, a giant brachiosaurid similar to Sauroposeidon was described in 2004, by Darren Naish
Darren Naish
Darren Naish is a vertebrate palaeontologist and science writer. He obtained a geology degree at the University of Southampton and later studied vertebrate palaeontology under British palaeontologist David Martill at the University of Portsmouth, where he obtained both an M. Phil...
and colleagues, and is from the Early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
period of England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
. Known only from two neck vertebrae, it was apparently similar in some details to Sauroposeidon and perhaps similar in size. Its discovery highlights the similarity seen between Early Cretaceous North American and European dinosaurs.
External links
- A non-technical article on Dino Land, with links to various news reports.