Mesozoic era
252–66 million years ago: dinosaurs, pterosaurs and sea monsters
The Mesozoic era, from about 252 to 66 million years ago, is split into the Triassic, Jurassic and Cretaceous periods. Dinosaurs appeared in the Triassic, came to dominate land in the Jurassic, and in the Cretaceous produced some of the most famous animals ever found, from Tyrannosaurus to Triceratops. The era ended with the asteroid impact at Chicxulub, which killed off all non-bird dinosaurs.
Dinosaurs were never alone. Pterosaurs, which were flying reptiles rather than dinosaurs, ruled the skies; ichthyosaurs, plesiosaurs and mosasaurs hunted in the seas; giant crocodile relatives lurked in rivers. Small furry mammals and the first birds lived alongside them, and both lineages survived the extinction.
This is the largest part of the wheel, full of dinosaurs and the animals that lived around them. The odds of becoming a Tyrannosaurus are the same as becoming a mouse-sized Morganucodon hiding from it.
Also on the wheel in this era
Carcharodontosaurus, Albertosaurus, Gorgosaurus, Tarbosaurus, Daspletosaurus, Suchomimus, Irritator, Ceratosaurus, Eoraptor, Gallimimus, Struthiomimus, Ornithomimus, Citipati, Gigantoraptor, Mononykus, Sinosauropteryx, Guanlong, Proceratosaurus, Majungasaurus, Abelisaurus, Rugops, Mapusaurus, Acrocanthosaurus, Concavenator, Cryolophosaurus, Megalosaurus, Torvosaurus, Afrovenator, Australovenator, Fukuiraptor, Beipiaosaurus, Apatosaurus, Camarasaurus, Patagotitan, Dreadnoughtus, Saltasaurus, Dicraeosaurus, Mamenchisaurus, Euhelopus, Shunosaurus, Alamosaurus, Rapetosaurus, Magyarosaurus, Riojasaurus, Lessemsaurus, Jobaria, Rebbachisaurus, Limaysaurus, Demandasaurus, Centrosaurus, Pachyrhinosaurus, Psittacosaurus, Kentrosaurus, Huayangosaurus, Euoplocephalus, Nodosaurus, Polacanthus, Corythosaurus, Lambeosaurus, Edmontosaurus, Ouranosaurus, Muttaburrasaurus, Stegoceras, Hypsilophodon, Dimorphodon, Pterodactylus, Tapejara, Nyctosaurus, Dsungaripterus, Anhanguera, Tropeognathus, Pterodaustro, Ornithocheirus, Tupandactylus, Germanodactylus, Anurognathus, Darwinopterus, Campylognathoides, Istiodactylus, Zhejiangopterus, Caiuajara, Ophthalmosaurus, Temnodontosaurus, Plesiosaurus, Cryptoclidus, Pliosaurus, Kronosaurus, Tylosaurus, Platecarpus, Nothosaurus, Placodus, Henodus, Mixosaurus, Shonisaurus, Dakosaurus, Metriorhynchus, Simosuchus, Desmatosuchus, Rutiodon, Gracilisuchus, Proterosuchus, Anatosuchus, Ichthyornis, Jeholornis, Sapeornis, Enantiornis, Longipteryx, Patagopteryx, Hongshanornis, Belemnite, Cretoxyrhina, Hybodus, Mawsonia, Onchopristis, Protostega, Cynognathus, Volaticotherium, Didelphodon, Steropodon, Sinodelphys, Mesolimulus, Catopsbaatar.