The dinosaurs are some of the most important animals in Earth’s history. They are widespread across every continent, even in Antarctica, as the form of birds. They have made their way across popular culture for over 150 years, and ruled the earth for 245 million years. Dinosaurs are present in a variety of forms, from the small Scapornithes to the giant giraffasaurs, from the peaceful humbriges to the ferocious Indominus rexoides, all of which exist in a alternative version of Earth.
Dinosaurians first possibly evolved in the Early Triassic, in the form of the Nyasasaurus, which looked and behaved like a cretaceous Ornithomimosaur, which are fast running, bird like dinosaurs, which shows how similar to birds dinosaurs really are. Then, in the Late Triassic, there was a explosive diversification of the non- avian dinosaurs, with forms like Plateosaurus, Liliensternus, Coelophysis, Herrerasaurus, Eocursor and Technosaurus. These Early dinosaurs were in stiff competition with other non- dinosaurian reptiles, like Dicynodonts, Rausuchians and Phytosaurs. However, the Triassic- Jurassic Extinction killed off their competitors, so they had another explosive radiation, filling all sorts of niches. By the Early Cretaceous, all modern forms had evolved, with Tyrannosaurs, Ceratopsians, Hadrosaurs, Ornithomimosaurs etc. roaming the north, and Abelisaurs, Sauropods, and Spinosaurs dominating the South. In or time line, at the end of the Cretaceous, all of them except for birds went extinct. In AE, however, they continued to diversify.
The dinosaurians can be distinguished into two groups: the saurischians, which include everything from Sauropods to Birds and the ornithischians. Saurischians are the more diverse and widespread than their herbivorous competitors. In AE, it is much too confusing to actually classify theropods, as one cannot actually just go “Ok, the Kamikaze Bird is a bird, while the Dracula Raptor is not”. Despite their similarities, it is not certain how close a Kamikaze Bird actually is to a Dracula Raptor. Same with Ornithiscians. One could not distinguish a Greater Honker with a Side Nose. Theropod anatomy shows distinct features, like a upright, horizontal stance, all have either teeth or a beak like teeth structure, all have three claws or less, and all have a long balancing tail, to help them while running. The Sauropods, however, are the exact opposite, with a horizontal quadruped stance, a long neck and tail, and five- toed elephantine feet. All Saurischians are either Carnivorous, Omnivorous, or herbivorous, each groups experimenting on the other. Abelisaurs, the only featherless carnivores of AE, are quite successful, and contain the Indominus rexoides, which resembles the actual Indominus rex of Jurassic World, and was named in its honour, and thus have no known common name. Coelurosaurs, however, are even more successful, with all forms being Maniraptors aside from Courtosaurs, Tyrannosaurs, and the Harpy. More advanced Coelurosaurs, the Maniraptorans, are small to huge and resembled goofy chickens. The Maniraptorans are sorted (in order of the most advanced) from the Ornithomimosaurs, which resemble Ostriches and Emus, the Alvarezsaurs, which pluck their way through termite mounds like Anteaters, the Therizinosaurs, which plunder their way through the plains like Bison of Home Earth, the Oviraptorosaurs, who bark at each other like Jurassic Park Velociraptors, the Dromaeosaurs, which show their thrift like birds in your garden and hunt like Hawks, the Neoscanisoropterygians, who clamber up Aussie and Indonesian trees like Monkeys, and the Birds, which could twitter and climb in your own back yard. Birds, which are so diverse, were once considered a clade of their own, and are now known, to be advanced Dromeaosaurs that have adapted to trees. Several orders of birds exist, from the Enantiornithes, which are called Opposite Birds, the Ichthyornithiformes, which are toothed birds descended from the popular Ichthyornis. Other odd birds include sparrow rip-offs, which are called Scapornithes, have their own oddities, with Raptor mimics in the form of the Kamikaze Birds. Hesperornithiformes, those long necked, toothed sea birds, are also present, and mimic penguins to some extent. Simply put it, passerines (birds such as sparrows) never evolved.
Ornithiscians, which consisted of Ornithopods, Ceratopsians, Pachycephalosaurs, Ankylosaurs and Stegosaurs, have diversified from their ancestors, producing many unique forms. However, they are not as diverse and widespread as their relatives, the Saurischians. However, they are present in every continent except for Antarctica. Ornithopods, which evolved from small bipedal creatures like Eocursor. They split into two super orders, the Iguanodontians, and the Australiornithopoda, which are the dominant herbivores/ carnivores of Australia and Papua New Guinea. Iguanodontians are more diverse, evolving from smallish bipedal creatures like Dryosaurus and Othnielia. They are the most successful Ornithiscians alive today, with over 200 members.
The Ceratopsians, which were typified by giants such as Triceratops, Centrosaurus and Pachyrhinosaurus, were almost wiped off the face of the earth in the Eocene, with only a few small members, which were likely descendants of Protoceratops or Leptoceratops, had enough chance to hold their niches as dominant, Rhinoceros/ Hippopotamus analogues, with great hulking bodies and magnificent horns. Pachycephalosaurs, however, shrunk in range. They now exist in Asian and European mountains as Goat analogues, albeit most are bipedal. Small Ceratopsians are extremely common in AE, as Goat, Sheep and Pig analogues, with frills displaying and effective horns.
Ankylosaurians have greatly decreased in diversity, and exist in North Africa, Papua New Guinea, and Australia only, and are either descended from Struthiosaurus or Minmi. Today, they are very scarce, compared to their former glory, as other creatures have taken their place.
In the totality of their 245 million reign, they conquered environments like the Air, Seas and the Land. One cannot tread on one place without seeing them. Totally, Dinosaurs are indestructible, and will remain so, even if it’s in the form of Birds.
Saurischians – giraffasaurs, kamikaze Birds, etc.
Sauropoda (titanosaurs) – large, specialised high/low browsers
Abelisaurs (Indominus, ghouls, etc.) – fearsome scaled predators
Courtosaurs (long-caws, dome eyes, etc.) – Aussie's own coelurosaurs
Neoscanisoropterygia – The Pacific's anteater parodies
Tyrannosauroidea – (gourmands, kumvus etc.) – ravenous predators of the north
Antiqueraptora (Cootues and Foxraptors) Small, Malagasy predators.
Maniraptora (Therizinosaurs, Jackal Birds, etc.) Any creatures close to birds.
Therizinosauroidea (Yeti Birds, Marine Claws etc.) Large, duck like herbivores.
Oviraptorosauria (Jackal Birds, Ovistriches, Oemus etc.) The archaic egg thieves.
Ornithomimosauria (Runner Mimes, Chuckles etc.) Medium sized running omnivores. Troodontidae (Caraptors) Smallish, intelligent and fluffy predators of the Americas. Eudromaeosauria (Dracula raptors, Spine Clucks, Arbroclaws etc.) Small to large sized Dromeaosaurs of the Old and New World.
Rahonavia (Bomber Birds, Hopper Drops, etc.) Madagascar’s unique answer to Deinonychosaurs.
Alvarezsauria (Kakalvies, Mountain Hoppers etc.) Australian, European, Indonesian, Madagascan and Asian ant eating Dinosaurs.
Confuciusornithia (Eagles of Paradise) Odd, seemingly two tailed Old World Birds of Paradise.
Enantiornithes (Avisaurs, Hawks of Paradise etc.) Old and New World predators with teeth and fascinating tails.
Hesperornithes (Arctoparrots, Northguins, Slobber Birds etc.) Usually long necked, sea adapted birds.
Ichthyornithiformes (Griffon Gulls, Vulture Hawks etc.) A diverse, toothed group of usually Aquatic hunters.
Neognathae (Chickens, Geese, Kingfishers etc.) Almost all familiar birds.
Ornithiscians (Australiornithopods, Ceratopsians etc.)
Ceratopsians (Bull Horns, Giga Horns etc.) Old and New World horned herbivores that fill small- large hippo analogues.
Pachycephalosauria (Goatocephale, Mountain Devils etc.) Domed, medium sized herbivores of the old world.
Ankylosauria (Desert Tanks, Neodosaurs etc.) African, Asian, Indonesian and Australian Dinosaurian tanks.
Duogonisauridae (Duogongohadrians) Semi aquatic Hadrosaur relatives.
Elasmaria (Opabimids, Trunkhadras, South Cursors etc.) A clade of South American endemic herbivores that have had their own radiation.
Australiornithopoda (Ozziehadros, Corn Horns, Jackalopods etc.) Odd, Hadrosaur mimics of Australia and Papua New Guinea.
Heterovenatora (Cursor Pods, Nuzzle beasts etc.) Australia and Papua New Guinea’s carnivorous Ornithopods.
Dendrodryosauria (Koalapods, Arboroorniths, Cornucopias etc.) Small to medium sized, mostly Arboreal Indonesian, Madagascan, and Australian basal Ornithopods.
Hadrosauria (Hadrulks, Cornodonts, Zebontosaurs etc.)
Edmontosauria (Hadrulks, Swamp Hadroo, Zebontosaurs etc.) Medium to large sized Hadrosaurs of the New World descended from Edmontosaurus and Ugrunaaluk.
Artiodactylopoda (Hippodonts, Sail Camels, Ornitholopes etc.) Small to medium sized basal Hadrosaurs of the Old World, which greatly resemble Artiodactyls of RL.