Instruct: Given a question, retrieve documents that can help answer the question.
Query: How tall was Dimetrodon?
"Dimetrodon" was a quadrupedal, sail-backed synapsid. Most "Dimetrodon" species ranged in length from and are estimated to have weighed between . The largest known species of "Dimetrodon" is "D. angelensis" at and the smallest is "D. teutonis" at . The larger species of "Dimetrodon" were among the largest predators of the Early Permian, although the closely related "Tappenosaurus", known from skeletal fragments in slightly younger rocks, may have been even larger at an estimated in total body length. Although some "Dimetrodon" species could grow very large, many juvenile specimens are known.
"Brontosaurus" was a large, long-necked quadrupedal animal with a long, whip-like tail, and forelimbs that were slightly shorter than its hindlimbs. The largest species, "B. excelsus", weighed up to and measured up to long from head to tail. For comparison, the current largest land animal, the average male African bush elephant is 3.20 m (10.5 ft) tall at the shoulder and has a body mass of 6,000 kg (13,228 lb) or 6.6 short tons.
The team discovered the remains of the largest dinosaur to walk in the southern parts of Africa , namely a 190-million-year-old fossilised egg of a Massospondylus dinosaur. This dinosaur lived in the Late Triassic and Early Jurassic, a period from about 230-million years ago to about 185-million years ago. The Massospondylus wandered about in great herds, migrating back and forth between what would millions of years later become Southern Africa and Russia, when the southern super-continent, Gondwana, was still intact. The rocks that were laid down during this period are called the Stormberg Group of rocks, and it is in rocks of the Stormberg Group that the fossils of Massospondylus and other dinosaurs were found. Massospondylus dinosaurs hatched from eggs not much larger than a hen’s egg, but grew into big creatures 5 to 6 metres long. They had large bodies, long necks and small heads, and long tails.
Pteranodon (; from Greek πτερόν ( pteron, "wing") and ἀνόδων (anodon, "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with wingspans over 8 meters (26 feet). They lived during the late Cretaceous geological period of North America in present-day Kansas, Alabama, Nebraska, Wyoming, and South Dakota. More fossil specimens of "Pteranodon" have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway.
This minor planet was named after Brontosaurus, a gigantic quadruped sauropod dinosaurs, which walked on all four legs and lived in the Upper Jurassic. Adult individuals measured up to 20 meters and had a weight of up to 20 tons. Many Fossils have been found in the United States. Brontosaurus is one of the best-known dinosaurs. The official naming citation was published by the Minor Planet Center on 20 November 2002 ().
The largest land mammal extant today is the African bush elephant. The largest extinct land mammal known was long considered to be "Paraceratherium orgosensis", a rhinoceros relative thought to have stood up to tall, measured over long and may have weighed about 17 tonnes. In 2015, a study suggested that one example of the proboscidean "Palaeoloxodon namadicus" may have been the largest land mammal ever, based on extensive research of fragmentary leg bone fossils from one individual, with a maximum estimated size of 22 tonnes.
On occasion, the bone of a fossilised predator is preserved well enough to retain recognizable proteins that belong to the species it consumed when alive. Stable isotope analysis of these proteins has shown that "Smilodon" preyed mainly on bison and horses, and occasionally ground sloths and mammoths, while "Homotherium" often preyed on young mammoths and other grazers such as pronghorn antelope and bighorn sheep when mammoths were not available.
Adult "Pteranodon" specimens may be divided into two distinct size classes, small and large, with the large size class being about one and a half times larger than the small class, and the small class being twice as common as the large class. Both size classes lived alongside each other, and while researchers had previously suggested that they represent different species, Christopher Bennett showed that the differences between them are consistent with the concept that they represent females and males, and that "Pteranodon" species were sexually dimorphic. Skulls from the larger size class preserve large, upward and backward pointing crests, while the crests of the smaller size class are small and triangular. Some larger skulls also show evidence of a second crest that extended long and low, toward the tip of the beak, which is not seen in smaller specimens.
It is based on the type specimen or holotype BPV-078, an incomplete skeleton and skull. Its skull, including a large crest, was toothless and similar to that of "Pteranodon". The skull lacks the point of the snout but it was in life less than 200 millimeters long (7.9 inches), and the animal had a wingspan of about 1.1 meters (3.6 feet). A second specimen, D2526, described in 2006, had a larger wingspan. Despite its similarities to "Pteranodon", "Eopteranodon" was not placed into a family by its describers, who put it into the clade Pteranodontia as "incertae sedis" (uncertain position).
Though similar to "Palaeopropithecus", "Archaeoindris" was significantly larger and more robust. "Archaeoindris" was one of the largest primates to ever evolve, and was the largest-known strepsirrhine primate, weighing an estimated . It was roughly the size of an adult male gorilla, which was first noted by Lamberton.
The diet of "Pteranodon" is known to have included fish; fossilized fish bones have been found in the stomach area of one "Pteranodon", and a fossilized fish bolus has been found between the jaws of another "Pteranodon", specimen AMNH 5098. Numerous other specimens also preserve fragments of fish scales and vertebrae near the torso, indicating that fish made up a majority of the diet of "Pteranodon" (though they may also have taken invertebrates).
"Smilodon" was around the size of modern big cats, but was more robustly built. It had a reduced lumbar region, high scapula, short tail, and broad limbs with relatively short feet. "Smilodon" is most famous for its relatively long canine teeth, which are the longest found in the saber-toothed cats, at about long in the largest species, "S. populator". The canines were slender and had fine serrations on the front and back side. The skull was robustly proportioned and the muzzle was short and broad. The cheek bones (zygomata) were deep and widely arched, the sagittal crest was prominent, and the frontal region was slightly convex. The mandible had a flange on each side of the front. The upper incisors were large, sharp, and slanted forwards. There was a diastema (gap) between the incisors and molars of the mandible. The lower incisors were broad, recurved, and placed in a straight line across. The p3 premolar tooth of the mandible was present in most early specimens, but lost in later specimens; it was only present in 6% of the La Brea sample. There is some dispute over whether "Smilodon" was sexually dimorphic. Some studies of "S. fatalis" fossils have found little difference between the sexes. Conversely, a 2012 study found that, while fossils of "S. fatalis" show less variation in size among individuals than modern "Panthera", they do appear to show the same difference between the sexes in some traits.
"Dinoponera" contains one of the largest species of ants in the world, with female "Dinoponera gigantea" specimens measuring in length. Size is the most obvious character distinguishing "Dinoponera" from other genera. The only other ants with a worker caste approaching this size are "Paraponera clavata" (the bullet ant) and the larger "Pachycondyla" such as "P. crassinoda", "P. impressa" and "P. villosa". "Paraponera clavata" is easily separated by its anvil-shaped petiole with a spine on the ventral surface, highly sculptured body and deep antennal scrobes. "Pachycondyla" is regarded as the sister taxa to "Dinoponera". "Dinoponera", in addition to their size, are distinguishable from "Pachycondyla" by the presence of two laterally projecting clypeal teeth and rows of spines on the pygidium and hypopygidium.
The Permian era "Cotylorhynchus", from what is now the southern United States, probably was the largest of all synapsids (most of which became extinct 250 million years ago), at and 2 tonnes. The largest carnivorous synapsid was "Anteosaurus" from what is now South Africa during Middle Permian era. "Anteosaurus" was long, and weighed about .The largest living reptile, a representative of the order Crocodilia, is the saltwater crocodile ("Crocodylus porosus") of Southern Asia and Australia, with adult males being typically long. The largest confirmed saltwater crocodile on record was long, and weighed about . Unconfirmed reports of much larger crocodiles exist, but examinations of incomplete remains have never suggested a length greater than . Also, a living specimen estimated at and has been accepted by the Guinness Book of World Records. However, due to the difficulty of trapping and measuring a very large living crocodile, the accuracy of these dimensions has yet to be verified. A specimen named Lolong caught alive in the Philippines in 2011 (died February 2013) was found to have measured in length.
Gigantopithecus (from the Ancient Greek ' "giant", and ' "ape") is an extinct genus of ape that existed from perhaps nine million years to as recently as one hundred thousand years ago, at the same period as "Homo erectus" would have been dispersed, in what is now India, Vietnam, China and Indonesia placing "Gigantopithecus" in the same time frame and geographical location as several hominin species. The primate fossil record suggests that the species "Gigantopithecus blacki" were the largest known primates that ever lived, standing up to and weighing as much as , although some argue that it is more likely that they were much smaller, at roughly in height and in weight.
The press release in 1999 immediately garnered international media attention, which led to many (inaccurate) news reports of "the largest dinosaur ever!". While "Sauroposeidon" likely represents the tallest known dinosaur taxon, it does not hold records for either the longest or most massive. "Patagotitan" or "Argentinosaurus" make better candidates for the title "World's Largest Dinosaur" (presuming to ignore, as is conventional, "Amphicoelias"), though incomplete fossil evidence makes exact rankings impossible.
The "World's Largest Dinosaur" is the name of a model "Tyrannosaurus rex" located in the town of Drumheller in the Canadian province of Alberta. Built of fiberglass and steel, has a height of and a length of , considerably larger than the largest known specimens of the actual dinosaur which reached up to in length, and was up to tall at the hips. The dinosaur was built while former mayor Phil Bryant was in his term.
"Sinosauropteryx" was a small bipedal theropod, noted for its short arms, large first finger (thumbs), and long tail. The taxon includes some of the smallest known adult non-avian theropod specimens, with the holotype specimen measuring only in length, including the tail. However, this individual was relatively young. The longest known specimen reaches up to in length, with an estimated weight of .
Smilodon is a genus of the extinct machairodont subfamily of the felids. It is one of the most famous prehistoric mammals, and the best known saber-toothed cat. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats. "Smilodon" lived in the Americas during the Pleistocene epoch (2.5 mya–10,000 years ago). The genus was named in 1842, based on fossils from Brazil. Three species are recognized today: S. gracilis, S. fatalis, and S. populator. The two latter species were probably descended from "S. gracilis", which itself probably evolved from "Megantereon". The hundreds of individuals obtained from the La Brea Tar Pits in Los Angeles constitute the largest collection of "Smilodon" fossils.
According to his profile in the second issue of the U.K. Transformers magazine, Blackout stands 33 feet 5 inches tall, weighs 2.9 tons and has a maximum speed of 800 mph. The official guide to the Transformers video game says he's 33 feet tall. Both of these heights are much smaller than his alternate mode would suggest, and seem to contradict what Roberto Orci and Alex Kurtzman said about his size. However, in the video game's profile for him, it states that he is often seen "silently looming over Megatron's shoulder" indicating that he would have to be taller than Megatron, and therefore taller than 33 feet. His exact height seems to be a mystery. As size calculations from the Voyager class toy suggests, his height should be about 55 feet tall. Oddly the book "Ghosts of Yesterday" described him as being smaller than Optimus Prime, who is officially described as 28 feet tall.
Methods used to estimate the mass of large male "Pteranodon" specimens (those with wingspans of about 7 meters) have been notoriously unreliable, producing a wide range of estimates from as low as to as high as . In a review of pterosaur size estimates published in 2010, researchers Mark Witton and Mike Habib demonstrated that the latter, largest estimates are almost certainly incorrect given the total volume of a "Pteranodon" body, and could only be correct if the animal "was principally aluminium". Witton and Habib considered the methods used by researchers who obtained smaller mass estimates equally flawed. Most have been produced by scaling modern animals such as bats and birds up to "Pteranodon" size, despite the fact that pterosaurs have vastly different body proportions and soft tissue anatomy from any living animal.
The skull of "Dimetrodon" is tall and compressed laterally, or side-to-side. The eye sockets are positioned high and far back in the skull. Behind each eye socket is a single hole called an infratemporal fenestra. An additional hole in the skull, the supratemporal fenestra, can be seen when viewed from above. The back of the skull (the occiput) is oriented at a slight upward angle, a feature that it shares with all other early synapsids. The upper margin of the skull slopes downward in a convex arc to the tip of the snout. The tip of the upper jaw, formed by the premaxilla bone, is raised above the part of the jaw formed by the maxilla bone to form a maxillary "step." Within this step is a diastema, or gap in the tooth row. Its skull was more heavily built than a dinosaur's.
"Dimetrodon" is an early member of a group called synapsids, which include mammals and many of their extinct relatives, though it is not an ancestor of any mammal (which appeared millions of years later). It is often mistaken for a dinosaur in popular culture, despite having become extinct some 40 million years (Ma) before the first appearance of dinosaurs in the Triassic period. As a synapsid, "Dimetrodon" is more closely related to mammals than to dinosaurs or any living reptile. By the early 1900s most paleontologists called "Dimetrodon" a reptile in accordance with Linnean taxonomy, which ranked Reptilia as a class and "Dimetrodon" as a genus within that class. Mammals were assigned to a separate class, and "Dimetrodon" was described as a "mammal-like reptile". Paleontologists theorized that mammals evolved from this group in (what they called) a reptile-to-mammal transition.
Most of these studies give two thermoregulatory roles for the sail of "Dimetrodon": one as a means of warming quickly in the morning, and another as a way to cool down when body temperature becomes high. "Dimetrodon" and all other Early Permian land vertebrates are assumed to have been cold-blooded or poikilothermic, relying on the sun to maintain a high body temperature. Because of its large size, "Dimetrodon" had high thermal inertia, meaning that changes in body temperature occurred more slowly in it than in smaller-bodied animals. As temperatures rose in the mornings, the small-bodied prey of "Dimetrodon" could warm their bodies much faster than could something the size of "Dimetrodon". Many paleontologists including Haack have proposed that the sail of "Dimetrodon" may have allowed it to warm quickly in the morning in order to keep pace with its prey. The sail's large surface area also meant heat could dissipate quickly into the surroundings, useful if the animal needed to release excess heat produced by metabolism or absorbed from the sun. "Dimetrodon" may have angled its sail away from the sun to cool off or restricted blood flow to the sail to maintain heat at night.
Both "Sphenacodon" and "Dimetrodon" have been depicted with their short limbs splayed outward at 90 degrees from the body in a wide pushup position and with the tail (and even belly) dragging on the ground, similar to modern lizards and crocodiles. A sprawling stance is also typical for "Sphenacodon" and "Dimetrodon" skeletons as currently mounted in museums. However, trackways called "Dimetropus" (“"Dimetrodon" foot”) that match the foot configuration of large sphenacodontids show animals walking with their limbs brought under the body for a narrow, semi-erect gait without tail or belly drag marks. Such clear evidence for a more efficient upright posture suggests that important details about the anatomy and locomotion of "Sphenacodon" and "Dimetrodon" may not be fully understood. Some well preserved narrow "Dimetropus" tracks found in parts of the Prehistoric Trackways National Monument in New Mexico match the smaller size of "Sphenacodon", a genus known from skeletal fossils in the state, but could also come from a small "Dimetrodon".