Cryolophosaurus Fossil range: Early Jurassic
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Superorder: Dinosauria Order: Saurischia Suborder: Theropoda (unranked)  ?Tetanurae Genus: Cryolophosaurus
Binomial name
Cryolophosaurus ellioti Hammer & Hickerson, 1994

Cryolophosaurus (/kɹaɪ.əʊ'ləʊf.əʊ'sʊə.ʌs/ or /ˌkɹaɪəʊˈlɒfəsɔɹəs/, meaning "cold crest lizard") was a large bipedal dinosaur, with a bizarre crest on its head that looked like a Spanish comb. Massive cliffs in Zion Canyon consist of Lower Jurassic formations, including (from bottom to top): the Wingate Sandstone, the Kayenta Formation, and the massive Navajo Sandstone. ... Image File history File links No higher resolution available. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Digimon, the only known animals. ... Template:Tax more Chordates (phylum Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. ... Clades Subclass Anapsida Subclass Diapsida Infraclass Lepidosauromorpha Infraclass Archosauromorpha Sauropsids are a diverse group of mostly egg-laying vertebrate animals. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... Groups Sauropodomorpha    Saturnalia    Prosauropoda    Sauropoda Theropoda    Eoraptor    Herrerasauridae    Ceratosauria    Tetanurae       Aves(extant) Saurischians (from the Greek Saurischia meaning lizard hip) are one of the two orders/branches of dinosaurs. ... Subdivisions ?Eoraptor Herrerasauria Coelophysoidea Ceratosauria Cryolophosaurus Spinosauridae Carnosauria Coelurosauria Theropods (beast foot) are a group of bipedal saurischian dinosaurs. ... Groups Cryolophosaurus Spinosauroidea     Megalosauridae     Spinosauridae     Torvosauridae Neotetanurae     Carnosauria     Coelurosauria // Definition Tetanurae, meaning stiff tails, was named by Gauthier (1986) for a large group of theropod dinosaurs. ... In biology, binomial nomenclature is the formal method of naming species. ... This article or section does not cite its references or sources. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ...

Cryolophosaurus was discovered in Antarctica's Early Jurassic Hanson Formation (former the upper Falla Formation) by paleontologist Dr. William Hammer in 1991. It is the first carnivorous dinosaur to be discovered in Antarctica and the first dinosaur of any kind from the continent to be officially named. Dating from the Early Jurassic Period, it is also the earliest tetanuran theropod yet discovered. A paleontologist carefully chips rock from a column of dinosaur vertebrae. ... 1991 (MCMXCI) was a common year starting on Tuesday of the Gregorian calendar. ... This tigers sharp teeth and strong jaws are the classical physical traits expected from carnivorous mammalian predators A carnivore (IPA: ), meaning meat eater (Latin carne meaning flesh and vorare meaning to devour), is an animal that eats a diet consisting mainly of meat, whether it comes from live animals... The Jurassic Period is a major unit of the geologic timescale that extends from about 199. ... A geologic period is a subdivision of geologic time that divides an era into smaller timeframes. ... The Tetanurae are an extremely diverse group of Theropod dinosaurs, united by a few common features such as enlarged hands which have lost the fourth and fith digits to leave three fingers. ... Families See text Theropods (beast foot) are a group of bipedal, primarily carnivorous dinosaurs, belonging to the saurischian (lizard-hip) family. ...

Description

Cryolophosaurus was about 6 to 8 meters (20 to 26 feet) long, which is significantly smaller than the largest Allosaurus, which reached up to 12 meters (40 feet) in length. The metre, or meter (U.S.), is a measure of length. ... A foot (plural: feet or foot;[1] symbol or abbreviation: ft or, sometimes, ′ – a prime) is a unit of length, in a number of different systems, including English units, Imperial units, and United States customary units. ... Species type (Marsh, 1878) Paul, 1987 Mateus , 2006 jimmadseni Chure, 2000 vide Glut, 2003 Synonyms Creosaurus Marsh, 1878 Labrosaurus Marsh, 1879 Camptonotus Marsh, 1879  ?Epanterias Cope, 1878 Allosaurus (IPA: ) was a large (up to 11. ...

A high, narrow skull was discovered, 65 centimeters (25 inches) long. The peculiar nasal crest runs just over the eyes, where it rises up, perpendicular to the skull and fans out. It is furrowed, giving it a comb-like appearance. It is an extension of the skull bones, near the tear ducts, fused on either side to horns which rise from the eye sockets (orbital horns). While other theropods like the Monolophosaurus have crests, they usually run along the skull instead of across it. This article is being considered for deletion in accordance with Wikipedias deletion policy. ... An inch (plural: inches; symbol or abbreviation: in or, sometimes, ″ - a double prime) is the name of a unit of length in a number of different systems, including English units, Imperial units, and United States customary units. ... A comb A comb for people with hair loss. ... Monolophosaurus (one-crested lizard) was an allosaurid from Late Jurassic China. ...

The crest is too fragile to be used in combat, so it was probably used in mating displays.

Forests of the night

The remains of the Cryolophosaurus were found in the Hanson Formation with the remains of a very large prosauropod (related to plateosaurids like the Plateosaurus and Lufengosaurus), a small pterosaur, a mammal-like reptile (a tritylodont, which is a type of synapsid about the size of a rat), and another unknown theropod. There were also fossilized tree trunks two meters away. The site is about 4,000 meters (13,000 feet) above sea level. During the early Jurassic it was a river bed on the southern coast of the supercontinent of Gondwana. Families Plateosauridae (paraphyletic) Plesion Riojasaurus Massospondylidae Yunnanosauridae Prosauropoda or prosauropods were a group of early herbivorous dinosaurs that lived during the Late Triassic and early Jurassic periods. ... Binomial name Plateosaurus engelhardti von Meyer, 1837 Plateosaurus (flat lizard) was the largest dinosaur known to have existed during the Triassic Period of the Mesozoic era, reaching 6 to 10 m in length, and up to 700 kg in mass. ... Lufengosaurus, meaning Lufeng Lizard, was a prosauropod dinosaur which lived from the Late Triassic to the Middle Jurassic period in what is now southwestern China. ... Suborders Rhamphorhynchoidea * Pterodactyloidea Pterosaurs (, from the Greek πτερόσαυρος, pterosauros, meaning winged lizard, often referred to as pterodactyls, from the Greek πτεροδάκτυλος, pterodaktulos, meaning winged finger ) were flying reptiles of the clade Pterosauria. ... Mammal-like reptiles is a term used to describe the prehistoric animals that appear to be the reptilian ancestors of mammals. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Orders & Suborders Order Pelycosauria * Suborder Caseasauria Suborder Eupelycosauria * Order Therapsida * Suborder Biarmosuchia Suborder Dinocephalia Suborder Anomodontia Suborder Gorgonopsia Suborder Therocephalia Suborder Cynodontia * For complete phylogeny, see text. ... Petrified log at the Petrified Forest National Park A petrified tree from California Petrified wood is a type of fossil: it consists of fossil wood where all the organic materials have been replaced with minerals (most often a silicate, such as quartz), while retaining the original structure of the wood. ... In geology, a supercontinent is a land mass comprising more than one continental core, or craton. ... Gondwanaland redirects here. ...

This supports the idea that, even at high altitudes, early Jurassic Antarctica had forests populated by a diverse range of species, at least along the coast. Even though Antarctica was closer to the equator and the world was considerably warmer than today, the climate was still cool temperate. Recent models of Jurassic air flow indicate that coastal areas probably never dropped much below freezing, although more extreme conditions existed inland. This suggests that dinosaurs could endure relatively cool environments and even possibly survive snow. Temperate rainforest on Northern Slopes of the Alborz mountain ranges, Iran A dense growth of softwoods (a conifer forest) in the Sierra Nevada Range of Northern California A decidous broadleaf (Beech) forest in Slovenia. ... In biology, a species is one of the basic units of biodiversity. ... World map showing the equator in red For other uses, see Equator (disambiguation). ... In geography, temperate latitudes of the globe lie between the tropics and the polar circles. ...

Cryolophosaurus was found about 650 kilometers (400 miles) from the South Pole but, at the time it lived, this was about 1000km or so farther north. Cryolophosaurus, therefore, did not have to contend with the polar night. A kilometer (Commonwealth spelling: kilometre), symbol: km is a unit of length in the metric system equal to 1,000 metres (from the Greek words χίλια (khilia) = thousand and μέτρο (metro) = count/measure). ... A mile is a unit of length, usually used to measure distance, in a number of different systems, including Imperial units, United States customary units and Norwegian/Swedish mil. ... Amundsen-Scott South Pole Station. ... The polar night is the night lasting more than 24 hours, usually inside the polar circles. ...

The specimen was found in conjunction with a platter from the prosauropod which has led to speculation that it may have choked to death, although there is no concrete evidence of this one way or the other. Families Plateosauridae (paraphyletic) Plesion Riojasaurus Massospondylidae Yunnanosauridae Prosauropoda or prosauropods were a group of early herbivorous dinosaurs that lived during the Late Triassic and early Jurassic periods. ...

Classification

"Cryolophosaurus is also of significance because it represents the oldest known tetanuran from any continent — it is the only one from the Early Jurassic."

—William R. Hammer

Classification is difficult because the Cryolophosaurus has a mix of primitive and advanced characteristics. The leg bone (femur) has traits of early theropods, while the skull resembles much later species, like China's Sinraptor and Yangchuanosaurus. Originally, it was suspected that Cryolophosaurus might be a ceratosaur or even an early abelisaur, with some traits convergent with those of more advanced tetanurans. Mortimer ([1]) added Cryolophosaurus to the data from a study by Rauhut (2000) and found it to be even more primitive - a coelophysoid closely related to Dilophosaurus. This animal gives fuel to the argument that tetanuran Carnosaurs, like the Allosaurs, share a common ancestor and are closer than previously believed to the more "primitive" Ceratosaurus and its kin and that Cryolophosaurus could be the ancestor or close to the ancestor of both groups, accounting for the mixture of advanced and primitive characteristics. However, it is still believed by most researchers to be an early and primitive tetanuran. The most recent study that included Cryolophosaurus, Smith et al. (2005), recovered this position. Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Sinraptor The Sinraptor was a carnivore which was not only large, but also very quick for its size. ... Species Y. shangyouensis Dong, Li, Zhou & Chang, 1979 Y. magnus Dong, Zhou & Zhang, 1983 Paleo Template Project Yangchuanosaurus was a Sinraptor (or Allosaurid) theropod that lived in China during the Late Jurassic. ... The Ceratosauria are a group of Theropod dinosaurs defined as all theropods sharing a more recent common ancestry with Ceratosaurus than with birds. ... Species See text Abelisaurs were a group of Ceratosaurian dinosaurs which lived all over the southern hemisphere (with the exception of Tarascosaurus in Southern Europe) during the Cretaceous period. ... In evolutionary biology, convergent evolution is the process whereby organisms not closely related, independently evolve similar traits as a result of having to adapt to similar environments or ecological niches. ... The Tetanurae are an extremely diverse group of Theropod dinosaurs, united by a few common features such as enlarged hands which have lost the fourth and fith digits to leave three fingers. ... Species See text. ... Species  ? Dilophosaurus was a theropod dinosaur from the Early Jurassic Period. ... The Tetanurae are an extremely diverse group of Theropod dinosaurs, united by a few common features such as enlarged hands which have lost the fourth and fith digits to leave three fingers. ... Allosaurids were a family of medium to large sized carnivorous dinosaurs. ... // Ceratosaurus // meaning horned lizard, in reference to the horn on its nose (Greek keras/keratos meaning horn and sauros meaning lizard), was a large predatory dinosaur from the Late Jurassic Period, found in the Morrison Formation of North America, in Tanzania and possibly in Portugal. ... The Tetanurae are an extremely diverse group of Theropod dinosaurs, united by a few common features such as enlarged hands which have lost the fourth and fith digits to leave three fingers. ...

Discovery

Cryolophosaurus was originally collected during the 1990-91 austral summer, by William R. Hammer and his team, on Mount Kirkpatrick, in the Beardmore Glacier region of the Transantarctic Mountains. They were located in the siliceous siltstone of the Hanson Formation(formerly the upper Falla Formation) and dated to the Pliensbachian age of the early Jurassic. Mount Kirkpatrick is a lofty, generally ice-free mountain in Antarcticas Queen Alexandra Range. ... The Blue ice covering Lake Fryxell, in the Transantarctic Mountains, comes from glacial meltwater from the Canada Glacier and other smaller glaciers. ... Cryolophosaurus - One of the dinosaurs that was discovered in the Hanson layer of the Mt. ... Faunal stages are a subdivision of geologic time used primarily by paleontologists who study fossils rather than by geologists who study rock formations. ...

It was formally named and described in 1994 by William R. Hammer and William J. Hickerson, in the journal Science. The name Cryolophosaurus was dervived from the Greek κρυος (meaning 'cold' or 'frozen'), λοφος (meaning 'crest') and σαυρος (meaning 'lizard'). The name refers not the extreme conditions faced by the excavation team but to the relatively cool climate that the dinosaur lived in. Part of a scientific laboratory at the University of Cologne. ...

The remains include part of a skull (cranium), a jaw bone (mandible), parts of the backbone (30 vertebrae), hip bones (the illum, ischium, and pubis), leg bones (femur and fibula), an ankle bone (tibiotarsus) and foot bones (metatarsals). The skull was partially crushed by the Beardmore Glacier, but the crushed front portion of the skull has been reconstructed. Cranium can mean: The brain and surrounding skull, a part of the body. ... It has been suggested that this article or section be merged with jaw. ... A diagram of a thoracic vertebra. ... Human male pelvis, viewed from front Human female pelvis, viewed from front The pelvis is the bony structure located at the base of the spine (properly known as the caudal end). ... A man and a woman in the Pioneer plaque. ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the human body. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ... The metatarsus consists of the five long bones of the foot, which are numbered from the medial side (ossa metatarsalia I.-V.); each presents for examination a body and two extremities. ... The Beardmore Glacier (83º45´S 171º00´E) in Antarctica is the largest glacier in the world, with a length exceeding 160 km (100 mi). ...

During the 2003 season a field team returned and collected more material from the original site. In addition a second locality was discovered about 30 meters higher in the section on Mt. Kirkpatrick.

Hammer is a professor of geology and paleontology at Augustana College in Rock Island, Illinois and a curator at the Fryxell Geology Museum, where the holotype specimen currently resides. As of Summer 2006, he is planning a 2008 expedition to Antarctica. This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... Paleontology, palaeontology or palæontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. ... Augustana College is the name of two colleges in the U.S., both founded by Scandinavian immigrants: Augustana College (Illinois) Augustana College (South Dakota) This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Rock Island is a city located in Rock Island County, Illinois. ... A holotype is one of several possible types. ...

References

• Hammer, W.R., and W. J. Hickerson (1994). "A crested theropod dinosaur from Antarctica." Science, 264(5160): 828-830. May 6, 1994. (abstract)
• Smith, Hammer, and Currie (2005). "Osteology and phylogenetic relationships of Cryolophosaurus ellioti (Dinosauria: Theropoda): Implications for basal theropod evolution." Journal of Vertebrate Paleontology, 25(3): 116A-117A.

External links

• Transantarctic Vertebrate Paleontology Project, official website for the NSF project conducting research on Cryolophosaurus and related fauna (photos, research information, publication list, geology, project members...)
• Fryxell Geology Museum (photos, information)