The Dinosaurs
These animals were a large group of reptiles who were dominant land vertebrates for most of the Mesozoic era (245-65) million years ago. They appeared some 250 million years ago. They have an erect limb stance. This is very helpful to keep their bodies well above the ground. Dinosaurs are categorized in to two groups: saurischian (lizard-hipped) and ornithischians (bird-hipped).the dinosaurian were the most successful land vertebrates ever, and survived for 165 million years, until their extinction 65 million years ago.
Theropods
An enormously successful suborder of the saurischia, the bipedal (two footed) theropods emerges 230 million years ago. Theropods spanned the whole of the age of the dinosaurs (230-65 million years ago) and included most of the known predatory dinosaurs. It had small arms with sharp, clawed fingers; powerful jaws lined with sharp teeth; an s-shaped neck; long muscular hind limbs; and clawed usually four toed feet. Many theropods many have been warm-blooded; most were exclusively carnivorous.
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Yangchuanosaurs
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| Yangchuanosaurs |
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| Baryonyx |
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| Eustreptospondylus |
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| Dromiceiomimus |
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| Garudimimus |
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| Chirostenotes |
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| Avimimus |
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| Coelurus |
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| Procompsognathus |
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Struthiomimus
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Sauropodomorphs
These animals were herbivorous, usually quadrupedal (four-footed) dinosaurs.a suborder of the Saurischia, and they have small heads, bulky bodies, and long necks and tails. Many of these dinosaurs moved in herds protected from predatory theropods by their huge bulk and powerful tails.
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| Lufengosaurus |
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| Riojasaurus |
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Massospondylus
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| Anchisaurus |
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| Camarasaurus |
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| Cetiosaurus |
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| Shunosaurus |
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| Saltasaurus |
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| Diplodocus |
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Melanorosaurus
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Thyreophorans
These were a group of quadrupedal armored dinosaurs. They have rows of bony studs, plates or spikes along the back, which protected some from predators and may have helped others regulate body temperature. Up to 9m long, with a small head and small cheek teeth, Thyreophorans had shorter forelimbs than hind limbs and probably browsed on low level vegetation.
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| Stegosaurus |
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| Tuojiangosaurus |
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| Huayangosaurus |
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| Kentrosaurus |
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| Edmontonia |
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| Pinacosaurus |
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| Minmi |
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Euoplocephalus
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| Polacanthus |
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| Ankylosaurus |
Ornithopods
These were a group of ornithischian (bird-hipped) dinosaurs. These bipedal and qudrupedal herbivores had a horny beak, plant-cutting or grinding cheek teeth and a pelvic and tail region stiffened by bony tendons. They evolved teeth and jaws adapted to pulping vegetation and flourished from the middle Jurassic to the late Cretaceous period.
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| Ouranosaurus |
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| Iguanodon |
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| Parasaurolophus |
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| Camptosaurus |
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| Muttaburrasaurus |
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| Muttaburrasaurus |
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| Brachylophosaurus |
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| Lambeosaurus |
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| Hypacrosaurus |
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| Hadrosaurus |
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| Gryposaurus |
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| Corythosaurus |
Marginocephalians
These were a group of bipedal and quadrupedal ornithischian dinosaurs with a narrow shelf or deep, bony frill at the back of the skull. These animals were probably descended from the same ancestor as the ornithopods.
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| Stegoceras |
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| Triceratops |
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| Homalocephale |
