? Saurischia Conservation status: Fossil
Saurischia pelvis structure
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Superorder: Dinosauria Order: Saurischia Seeley, 1887
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. In 1888, Harry Seeley classified dinosaurs into two great orders, based on their hip structure. Saurischians are distinguished from the Ornithischians by retaining the ancestral configuration of bones in the hip. All carnivorous dinosaurs (the theropods) are members of the Saurischians, as are one of the two great lineages of herbivorous dinosaurs, the sauropodomorphs. At the end of the Cretaceous Period, all non-avian Saurischians became extinct during the Cretaceous-Tertiary extinction event. Saurischia pelvis structure. ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anenomes) Placozoa (trichoplax) Subregnum Bilateria (bilateral symmetry) Acoelomorpha (basal) Orthonectida (parasitic to flatworms, echinoderms, etc. ... Typical Classes Subphylum Urochordata - Tunicatas Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Orders See text. ... Orders Saurischia    Sauropodomorpha    Theropoda Ornithischia Dinosaurs are giant reptiles that dominated the terrestrial ecosystem for most of their 165-million year existence. ... Groups Saturnalia Prosauropoda Sauropoda The Sauropodomorpha were a group of long-necked, herbivorous dinosaurs that eventually dropped down on all fours and became the largest animals that ever the walked the earth. ... Binomial name Saturnalia tupiniquim Langer, Abdala, Richter & Benton, 1999 Saturnalia were a very early sauropodomorph dinosaur, from the Carnian faunal stage of the late Triassic period (227. ... 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. ... Families Brachiosauridae Camarasauridae Cetiosauridae Diplodocidae Dicraeosauridae Euhelopodidae Nemegtosauridae Titanosauridae Vulcanodontidae Sauropoda, the sauropods, are a suborder or infraorder of the saurischian (lizard-hipped) dinosaurs. ... Subdivisions ?Eoraptor Herrerasauria Coelophysoidea Ceratosauria Cryolophosaurus Spinosauridae Carnosauria Coelurosauria Theropods (beast foot) are a group of bipedal saurischian dinosaurs. ... Binomial name Eoraptor lunensis Sereno, Rogers, Forster & Monetta, 1993 Eoraptor lunensis was one of the worlds earliest dinosaurs. ... Genera Aliwalia Herrerasaurus ? Chindesaurus ? Caseosaurus Herrerasaurids are among the oldest known dinosaurs, appearing in the fossil record about 228 million years ago (mid-Triassic). ... The Ceratosauria are a group of Theropod dinosaurs defined as all theropods sharing a more recent common ancestry with Ceratosaurus than with birds. ... 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. ... For other meanings of bird, see bird (disambiguation). ... Families Many, see text. ... // Order may refer to: Religious Holy Orders, the rite or sacrament in which clergy are ordained The monastic orders, originating with Anthony the Great and Benedict of Nursia from circa 300 the military orders of the crusades the various chivalric orders established since the 14th century Honors Order (decoration) Legal... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... 1888 is a leap year starting on Sunday (click on link for calendar). ... Harry Govier Seeley (1839 – 1909) was the British paleontologist who detected that the dinosaurs fell into two great groups, the Saurischians and the Ornithischians, based on the nature of their pelvic bones and joints, and published his results in 1888, from a lecture he had delivered the previous year [1... Suborders Thyreophora Cerapoda    Ornithopoda    Marginocephalia Ornithischia is an order of beaked, herbivorous dinosaurs. ... A carnivore (KAR-nih-vohr) meaning meat eater (Latin carn = flesh + vorare = to devour) is an animal that eats a diet consisting solely of meat, whether it comes from live animals or dead (scavenging). ... Subdivisions ?Eoraptor Herrerasauria Coelophysoidea Ceratosauria Cryolophosaurus Spinosauridae Carnosauria Coelurosauria Theropods (beast foot) are a group of bipedal saurischian dinosaurs. ... A deer and two fawns feeding on some foliage In zoology, a herbivore is an animal that is adapted to eat primarily plant matter (rather than meat). ... Groups Saturnalia Prosauropoda Sauropoda The Sauropodomorpha were a group of long-necked, herbivorous dinosaurs that eventually dropped down on all fours and became the largest animals that ever the walked the earth. ... The Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period (about 135 mya) to the beginning of the Paleocene epoch of the Tertiary period (65 mya). ... The word Avian can refer to different things: .. Most commonly it is used referring to the class of animals named birds. Avians are a fantasy race in several fantasy settings. ... In biology and ecology, extinction is the ceasing of existence of a species or group of species. ... The Cretaceous-Tertiary (K-T or KT) extinction event, also known as the KT boundary, was a period of massive extinction of species, about 65. ...

T. rex pelvis and thighbones, showing the saurischian pelvis. Picture taken at the Field Museum of Natural History

The Saurischians were differentiated from the Ornithischians in the Late Triassic Period. The Ornithischians evolved a new hip structure, with the pubis rotating to become parallel with the ischium. This hip structure is similar to that of birds, and so Ornithischians are termed "bird-hipped" dinosaurs, while the Saurischians are "lizard-hipped". Ironically, the true bird-hip possessed by modern birds evolved from the lizard-hipped theropods in the Jurassic Period, an example of convergent evolution. T. rex pelvis and thighbones, image taken at Field Museum of Natural History File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... T. rex pelvis and thighbones, image taken at Field Museum of Natural History File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Field Museum of Natural History, Chicago The Field Museum of Natural History, in Chicago, Illinois, USA, sits on Lake Shore Drive next to Lake Michigan, part of a scenic complex known as Museum Campus Chicago. ... The Triassic is a Geologic period that extends from about 248 to 202 million years (My or megayears) before the present. ... A man and a woman in the Pioneer plaque. ... 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). ... Orders Many - see section below. ... The Jurassic period is a major unit of the geologic timescale that extends from about 195 million years BP at the end of the Triassic to 135 million years BP at the beginning of the Cretaceous. ... In evolutionary biology, convergent evolution describes the process whereby organisms not closely related independently acquire similar characteristics while evolving in separate and sometimes varying ecosystems. ...

While Seeley's classification has stood the test of time, there is a minority theory, first popularized by Robert Bakker in The Dinosaur Heresies that separates the theropods into their own group and places the two great groups of herbivorous dinosaurs (the sauropodomorphs and ornithischians) together in a separate group named as the Phytodinosauria ("plant dinosaurs") (Bakker), or Ornithischiformes (Cooper). Robert T. Bakker (Bob Bakker), born in Bergen, New Jersey, 1945, is a famous American paleontologist who has helped re-shape modern theories about dinosaurs, particularly by adding support to the theory that some dinosaurs were homeothermic (warm-blooded). ...

Taxonomy

• ORDER SAURISCHIA
  • ?Eoraptor
  • ?Herrerasauria
  • Suborder Sauropodomorpha
  • Suborder Theropoda