Order Saurischia. Order Saurischia. Lizard hipped (primitive type) - Pubis points forward and the ischium back (Same as the Triassic basal archosaurs)

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1 Dinosaurs: History and Evolution Dinosaurs: History and Evolution Order Saurischia Lizard hipped (primitive type) - Pubis points forward and the ischium back (Same as the Triassic basal archosaurs) Order Saurischia If teeth are reduced typically lost from back to front. Tend to lack armor. Saurischian Ornithischian Antorbital fenestra is retained.

2 Order Saurischia = beast foot Bipedal carnivores (most, but not all) Once divided into 2 main groups Carnosaurs = Flesh lizards = large Coelurosaurs = Hollow tail lizards = small Carnosaurs vs. Coelurosaurs Do not seem to be biological division, but are instead do to convergence ~ body size, lifestyle, etc. Cryolophosaurus (6m, Antarctica) Meat eaters Runners Theropods in General Theropods in General Meat eaters Clawed hands (3 digits) Most have serrated teeth Teeth are compressed Teeth held loosely in jaw Often very large brains Some with large eyes Lightly built skull Held together loosely Mobile neck Theropods in General Runners 5 sacral vertebrae Large pelvis for muscles S-shaped femur Elongate foot reduced digits Hollow bones Stiff tail Deinocheirus terrible hand

3 I. Basal Theropods A. Herrerasaurids - Late Middle Triassic of South America I. Basal Theropods B. Infraorder Ceratosauria - Late Triassic - Late Cretaceous (worldwide) - Fusion of the pelvic bones in the adults B. Infraorder Ceratosauria Coelophysis = hollow form meters long Oldest ceratosaur Late Triassic of North America - New Mexico Well known (100 s of individuals) Coelophysis Coelophysis B. Infraorder Ceratosauria Dilophosaurus = two crested lizard 2 crests on the head Crests common to ceratosaurs Jurassic of North America and China 5-7 meters

4 Dilophosaurus Dilophosaurus B. Infraorder Ceratosauria Ceratosaurus = horned lizard Pair of horns on the nasal bone Jurassic of North America 5-7 meters Ceratosaurus B. Infraorder Ceratosauria Carnotaurus = carnivorous bull Horns above orbits Cretaceous of Argentina 7.5 meters Carnotaurus

5 stiff tail Maxillary fenestra Tooth row does not extend past the antorbital fenestra Skull is short and narrow from side to side Orbit is higher & smaller than the antorbital fenestra Heavy crests over the orbits Mandibular fenestra is reduced 4 Groups Family Megalosauridae Family Allosauridae Carcharodontosaurids Clade Maniraptorifomres 1. Family Megalosauridae Megalosaurus = big lizard - mid Jurassic, Europe Megalosaurus 9 meters long

6 2. Family Allosauridae Allosaurus = different lizard - Late Jurassic of North America - 12 meters long Allosaurus Allosaurus Allosaurus Saurophaganax = Allosaurus

7 Saurophaganax = Allosaurus 3. Carcharodontosaurids Radiated worldwide Large carnivores Carcharodontosaurus = shark-tooth lizard - 1.5m skull! Carcharodontosaurus 4. Clade Maniraptoriformes = hand thief shape Share many derived characters with birds Elongate metacarpal III - reduced metacarpal I Modified caudal vertebrae Downwardly directed pubis Absence of the fourth trochanter on the femur 4. Clade Maniraptoriformes Compsognathus delicate jaw 3.5 kg. and 60 cm long Compsognathus

8 4. Clade Maniraptoriformes a. Family Dromaeosauridae have sickle claw Deinonychus terrible claw 3 meters long and about 1 meter high Deinonychus Deinonychus Deinonychus Pack Hunting by Deinonychus? Deinonychus

9 Deinonychus Deinonychus Deinonychus Deinonychus Velociraptor speedy raider/thief meters long (about 0.6 meters tall!) Deinonychus (top skull) and Velociraptor (bottom) Protoceratops vs. Velociraptor Protoceratops vs. Velociraptor

10 Velociraptor Velociraptor Velociraptor Velociraptor Utahraptor Thief of Utah Microraptor 0.5 m early K of China 5-7 meters long North America

11 Microraptor (Dromaeosaur) Glider? Microraptor Microraptor 4. Clade Maniraptoriformes b. Family Oviraptoridae Oviraptor egg raider/thief??? Oviraptor

12 Oviraptor Oviraptor egg raider/thief??? Bum rap? Oviraptor egg raider/thief??? Bum rap.yes! 4. Clade Maniraptoriformes c. Arctometatarsalia Narrow column foot 3 Families All share: three central metatarsals are triangular in cross section and compressed - metatarsal III often does not articulate with the astragalus 4. Clade Maniraptoriformes c. Arctometatarsalia - 3 Families 1. Family Tyrannosauridae Late Cretaceous of North America & Asia Tyrannosaurus = tyrant lizard Tyrannosaurus - Up to 14 meters long - Short forelimbs - Extra joint on the mandible = wider gape

13 Tyrannosaurus (left) and Dromaeosaur (right) Tyrannosaurus Tyrannosaurus Tyrannosaurus Sue (Tyrannosaurus rex) Sue (T. rex)

14 Sue (T. rex) Sue (T. rex) Sue (T. rex) Sue (T. rex) Skull of Sue (Tyrannosaurus rex) - Larson Brothers Was Sue really female? problems with negative evidence

15 Tyrannosaurus Hunter or Scavenger? Tyrannosaurus Hunter or Scavenger? Large olfactory bulbs Tyrannosaurus Hunter or Scavenger? Tyrannosaurus rex tooth Note serrations Tyrannosaurus Hunter or Scavenger? 4. Clade Maniraptoriformes c. Arctometatarsalia - 3 Families 2. Family Troodontidae Late Cretaceous of North America & Mongolia Saurornithoides = lizard bird form

16 Saurornithoides *Has been placed within the Dromaeosauridae by some workers Long slender skull Binocular vision Large brain 3 functional digits only (metatarsal III is the longest) 2 meters long 4. Clade Maniraptoriformes c. Arctometatarsalia - 3 Families 3. Family Ornithomimidae Late Jurassic though Late Cretaceous Very bird like with long arms and legs Struthiomimus Ornithomimus Gallimimus Family Ornithomimidae 1. Pelecanimimus polyodon 2. Harpymimus okladnikovi 3. Archaeornithomimus asiaticus 4. Archaeornithomimus bissektensis * 5. Garudimimus brevipes 6. Deinocheirus mirificus 7. Deinocheirus sp. * 8. Ornithomimus velox 9. Ornithomimus antiquus * 10. Ornithomimus edmontonicus * 11. Ornithomimus lonzeensis * 12. Ornithomimus sedens * 13. Sanchusaurus * 14. Orcomimus * 15. Gallimimus mongoliensis * 16. Gallimimus bullatus 17. Anserimimus planinychus * 18. Dromiceiomimus samueli * 19. Dromiceiomimus brevitertius 20. Struthiomimus altus Struthiomimus = ostrich mimic 3.5 meters long (Late K of Alberta) Struthiomimus Ornithomimus = bird mimic meters long Late K of North America

17 Gallimimus = Gallus or chicken mimic 4-6 meters long (Mongolia) Velociraptor!?