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Dinosaurs British Isles DINOSAURS of the BRITISH ISLES Dean R. Lomax & Nobumichi Tamura Foreword by Dr Paul M. Barrett (Natural History Museum, London) Skeletal reconstructions by Scott Hartman, Jaime A. Headden & Gregory S. Paul Life and scene reconstructions by Nobumichi Tamura & James McKay CONTENTS Foreword by Dr Paul M. Barrett.............................................................................10 Foreword by the authors........................................................................................11 Acknowledgements................................................................................................12 Museum and institutional abbreviations...............................................................13 Introduction: An age-old interest..........................................................................16 What is a dinosaur?................................................................................................18 The question of birds and the ‘extinction’ of the dinosaurs..................................25 The age of dinosaurs..............................................................................................30 Taxonomy: The naming of species.......................................................................34 Dinosaur classification...........................................................................................37 Saurischian dinosaurs............................................................................................39 Theropoda............................................................................................................39 Sauropodomorpha................................................................................................42 Ornithischian dinosaurs.........................................................................................44 Thyreophora.........................................................................................................44 Ornithopoda..........................................................................................................46 Marginocephalia...................................................................................................48 Heterodontosauridae............................................................................................49 Dinosaur discoveries: A brief introduction..........................................................50 Dinosaurs: A British ‘invention’.............................................................................50 Charles Darwin: The father of evolution...............................................................53 Early British discoveries.......................................................................................55 Crystal Palace Park..............................................................................................60 Modern palaeontology............................................................................................62 Dinosaur bones: The fossilisation process and the science of palaeontology..........................................................................................................68 What are fossils and how do they form?..............................................................68 Taphonomy and fossil finds..................................................................................70 Fossil preparation.................................................................................................72 Dinosaur trace fossils.............................................................................................74 Tracks and trackways...........................................................................................74 Coprolites, gastroliths and eggs...........................................................................77 Dinosaur contemporaries.......................................................................................80 A geological history of dinosaurs from the British Isles....................................86 Late Triassic.......................................................................................................86 The Lossiemouth Sandstone Formation: Saltopus, a possible early dinosaur................................................................................89 The oldest dinosaur tracks from the British Isles.............................................90 Rhaetian fissure fills in Wales and western-central England: Is Agnosphitys a primitive dinosaur?...............................................................93 Basal sauropodomorphs from the Late Triassic: Thecodontosaurus and relatives......................................................................94 Large bone fragments and Camelotia: A possible early sauropod................111 The Late Triassic theropods: Zanclodon and other fragments......................115 Early Jurassic...................................................................................................118 Scelidosaurus: A thyreophoran from the Charmouth Mudstone....................120 Sarcosaurus and other theropods from the Early Jurassic...........................126 Middle Jurassic................................................................................................131 The Aalenian Stage: The first record of stegosaurs in the world..................133 The Bajocian Stage: Magnosaurus, Duriavenator and others......................140 The Bathonian Stage....................................................................................146 The Scalby Formation: Tracks and trackways..........................................146 The Chipping Norton Limestone Formation (early Bathonian): Cruxicheiros and a microvertebrate site...................................................149 The Sharp’s Hill Formation (early Bathonian): The first significant stegosaur remains.....................................................155 The Taynton Limestone Formation (middle Bathonian): Megalosaurus and Iliosuchus...................................................................156 The White Limestone Formation (middle Bathonian): Ardley Quarry, a world-famous track site..................................................164 The Forest Marble Formation (late Bathonian): Cetiosaurus and Proceratosaurus............................................................166 The Valtos Sandstone, Kilmaluag, Duntulm and Lealt Shale Formations (late Bathonian): Scotland’s dinosaur-bearing formations........................178 The Cornbrash Formation (late Bathonian): Omosaurus vetustus, a dubious stegosaur...............................................182 The Callovian Stage......................................................................................183 The Kellaways Formation (early Callovian): Ornithopsis leedsii, a dubious sauropod...................................................183 The Oxford Clay Formation (middle Callovian to early Oxfordian): Loricatosaurus, Callovosaurus, Cetiosauriscus, Eustreptospondylus and Metriacanthosaurus...........................................................................184 Late Jurassic....................................................................................................205 The Corallian Group (Oxfordian): Indeterminate thyreophorans and theropods.................................................206 The Kimmeridge Clay Formation and other Kimmeridgian–Tithonian localities: Dacentrurus, Cumnoria and Juratyrant..........................................209 Early Cretaceous..............................................................................................226 The Purbeck Limestone Group: Echinodon, Owenodon and Nuthetes.........227 Dinosaur trace fossils in the Purbeck Limestone Group.........................236 The Wealden Group......................................................................................241 The Ashdown and Wadhurst Clay Formations (late Berriasian to middle Valanginian): Barilium, Hypselospinus, some sauropods and a tiny maniraptoran...........................................................................244 The Tunbridge Wells Sand and Grinstead Clay Formations (late Valanginian): Hylaeosaurus, Valdoraptor, the problematic Pelorosaurus and Becklespinax..............................................................256 The Wessex, Weald Clay and Vectis Formations (Hauterivian to early Aptian): A plethora of dinosaur remains..........................................269 Thyreophorans: Polacanthus...............................................................277 Ornithopods: Hypsilophodon, Iguanodon, Mantellisaurus and others............................................................................................285 Sauropods: Fragmentary remains point to high diversity.....................321 Theropods: Neovenator, Eotyrannus, Baryonyx and others................332 Dinosaur micro-remains: Sieving for dinosaurs...................................357 The Lower Greensand Group (early Aptian to early Albian): Mantellodon and fragmentary sauropods................................................359 The Gault Formation and Cambridge Greensand Member (late Albian to ‘Cenomanian’)...................................................................364 Anoplosaurus, dubious ankylosaurs and other fragmentary dinosaurs.............................................................................................364 The Upper Greensand Formation (late Albian to early Cenomanian): Scarce dinosaur remains.........................................................................373
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