Lecture 14 - Ornithopoda, Fall 2024 - PDF

LECTURE 14: Ornithopoda From Chapter 12 of Dinosaurs (4th Ed.) Andrey Atuchin  LECTURE 14: Ornithopoda From Chapter 12 of Dinosaurs (4th Ed.) Outline Ornithopoda – Hadrosaurs and their relatives  LECTURE 14: Ornithopod...

LECTURE 14: Ornithopoda From Chapter 12 of Dinosaurs (4th Ed.) Andrey Atuchin  LECTURE 14: Ornithopoda From Chapter 12 of Dinosaurs (4th Ed.) Outline Ornithopoda – Hadrosaurs and their relatives  LECTURE 14: Ornithopoda From Chapter 12 of Dinosaurs (4th Ed.) Objectives Understand the evolution of basal and derived Ornithopoda clades, with an empathize on Hadrosauridae Develop an understanding of the current thinking about the lifestyles and behaviours of ornithopods Ornithopoda Yandusaurus Oldest ornithopod fossil (Middle Jurassic) ORNITHOPODA ("bird feet") = Parasaurolophus and all taxa closer to it than to Triceratops Evolved in the Early Jurassic, survived until the end of the Cretaceous Ornithopoda Known from all continents ~ 2 to 14 m in length Basal members area agile bipeds Large derived forms large mostly quadrupedal Basal ornithopods (non- euornithopods) have 4 hoofed-toes supporting weight Euornithopoda have 3 functional hoofed-toes  Ornithopoda Orodromeus Thescelosaurus Late Cret., Montana Late Cret., NA Basal Ornithopoda Basal Iguanodontia Hypsilophodon Camptosaurus Late Jurassic, NA Early Cret., England Basal Euornithopoda Basal Ankylopollexia Iguanodon Edmontosaurus ~Early Cret., North Hem. Late Cret., NA Basal Iguanodontoidea Hadrosauridae Ornithopoda: Basal Ornithopods The systematics of basal ornithopods (and ornithischians) is highly volatile, in part because many taxa are known only from fragmentary specimens that can closely Burianosaurus resemble each other augustai from the Cenomanian of the Czech Because of this different Republic is analyses can recover known from one different most femur parsimonious trees (see Box 12.1) Art: Edyta Felcyn  Ornithopoda: Orodrominae Image: Manuel Gil Jaramillo Early to Late Cret. NA & Asia Oryctodromeus 1st dino to show burrowing and denning behaviour Adult & 2 juveniles found in ~2x1 m den Acromion Bipedal with forelimb process adapted for digging MOR/Varricchio Scap Oryctodromeus cubicularis, early L. Cret, MT & ID ula Scapular spine Varricchio Ornithopoda: Euornithopoda Euornithopoda Key character: Ventral edge of premaxilla is below the tooth row Tooth row Ventral edge of premaxilla Brachylophosaurus (Hadrosauridae)  Euornithopoda: Hypsilophodontidae Hypsilophodon foxii Early Cretaceous, Isle of Wight 1st discovered 1849; named 1869 ~2m long; ~ 20 kg; agile runner; Public Domain Pointed snout with sharp beak for snipping plants ossified tendons Sharp beak Hypsilophodon zone Scott Hartman Hypsilophodon foxii SVP Field Guidebook  Euornithopoda: Hypsilophodontidae ossified tenons Public Doma Hypsilophodon Cresent Books 1985 Galton 2009 Means ‘high- Dentary teeth crowned tooth’ Iguanodontia Iguanodon ~Early Cret., North Hem. Basal Iguanodontoidea Camptosaurus Late Jurassic, NA Basal Ankylopollexia Edmontosaur us Late Cret., NA Iguanodontia Iguanodontia: All ornithopods more closely related to Parasaurolophus than to Hypsilophodon Diamond-shaped tooth crowns Enlarged nares Sacral neural spines elongated 1st phalanx in manual digits II-IV longest  IGUANODONTIA vs. basal ornithopods Larger & heavier Enlarged naris Toothless premaxilla Diamond-shaped tooth crowns Increased sideways and backwards motion of the dentaries during chewing due to well- developed Iguanodon pleurokinetic hinge in upper jaw  Iguanodontia: Basal Iguanodontians Many were facultative bipeds Oldest iguanodontian is the Middle Jurassic (dryosaurid Callovosaurus) Iguanodontians common in the Late Jurassic & widespread in E Cret Most abundant large animals in most Callovosauru ecosystems,  Iguanodontia: Basal Iguanodontians Camptosaurus, L Jurassic, W US Dryosaurus, L Jurassic, W US Thomas (2015: fig. 2). Tenontosaurus skull, Antlers Fm, Oklahoma Tenontosaurus, E Cret, W US Skeletons: Scott Hartman  Iguanodontia: Basal Iguanodontians Tenontosaurus is one of the most common dinosaurs in the Early Cret 75% of of all Tenontosaurus localities western NA contain remains Deinonychus; size difference (8 vs. 3 m for adults) sugges pack hunting Image: DustDevil Image: FineArtAmerica  Iguanodontia: Iguanodontoidea Iguanodontoidea: Longer, broad snouts Much larger size Thumb spike (digit I) Digit V opposable Digits II & III robust with large, rounded weight-bearing unguals Callovosauru Iguanodontoidea: Basal Iguanodontoideans Iguanodontoidea: Longer, broad snouts Much larger size Thumb spike (digit I) Digit V opposable Digits II & III robust with large, rounded weight-bearing unguals Callovosauru  Iguanodontoidea: Basal Iguanodontoideans Iguanodon Ouranosaurus Iguanodon D Evans II III  Iguanodontoidea: Basal Iguanodontoideans Iguanodon Early Cretaceous, Europe Adults up to 10 m; ~3 tons Named in 1825 by Gideon Scott Hartman Mantell; 2nd dino named 38 skeletons from Belgium coal mine (1878) at 332 m 15 individuals from a BB in Germany; sociality Forelimb ~ 75% hindlimb  Iguanodontoidea: Basal Iguanodontoideans Small ‘crest’ Ouranosaurus Early Cret, Niger – Elrhaz Fm ~ 8 m in length; ~ 4 tons Creative Commons Premaxilla Tall neural toothless; 1 row of spines replacement teeth; 1st & 2nd generation teeth form continuous bite surface spike Small crest in front Scott Hartman Iguanodontoidea: Hadrosauridae Cretaceous; globally distributed Relatively large; > 14 m in length (Shantungosaurus) Like other iguanodontians, they were capable of functioning both bipedally and quadrupedally, with the dominant mode quadrupedal The obvious “duck bill” was actually a flaring of the premaxilla and the predentary that were covered by a keratin-covered beak (rhamphotheca) Good evidence for gregariousness &  Hadrosauridae HADROSAURI NAE LAMBEOSAURI NAE iliu m pub is ourtesy Tom Holtz Booted  Hadrosauridae Dominant large herbivores in Late Cret ecosystems in North Am. Also in Asia, EU, SA, Antarctica & Africa Hadrosaurinae: Two major clades: Brachylophosaurus, L Cret, AB HADROSAURINAE (‘solid-crested’) LAMBEOSAURINE (hollow-crested) Up to 15m in length; 2 m skulls Exclusively Late Cretaceous in age. Cranial crest formed by nasal bone Tall, symmetrical lancelet tooth Lambeosaurinae: Dental battery with 3 or more Corythosaurus, L Cret, AB ambridge 2016  Hadrosauridae Hadrosaurids vs. basal Iguanodontia: Further expansion of the snout ("duck bill") Further increase in # of tooth positions Hadrosaurid: Grinding dental battery forms Lambeosaurus continuous grinding surface Teeth of greater structural complexity than all other vertebrates Iguanodontia:  Hadrosauridae: Dentition Image: Notismro Edmontosaurus Dentary, medial view of tooth battery Hadrosaurs were built for chewing & grinding food Dental batteries: Up to 1400 diamond-shaped, tightly- packed teeth 5 replacement teeth constantly pushing D Evans Hadrosauridae: Dental Histology Hadrosaurid teeth are individually complex Research by Erickson et al. 2012 has shown that each tooth is comprised of at least 6 different dental tissues This makes hadrosaurid teeth more complex than those of mammals, including horses Combined with continuous tooth development & replacement, this means hadrosaurids have the most sophisticated dental system in vertebrates Erickson, Gregory M., et al. 2012. Complex dental structure and wear biomechanics in  Hadrosauridae: Abundance Hadrosaurs were the most abundant dinosaurs in the Late Cretaceous of NA Likely moved in large herds at least part of the year Efficient jaws maximized the energy available from plant resources Karen Carr rom: Brinkman et al. 1993 Hadrosauridae: Social Behaviour (Bonebeds) Monodominant hadrosaur bonebeds are well known from NA & Asia, with dozens of Edmontosaurus BBs from the L Campanian & Masstrichtian of Canada and the US Some preserved >10000 disarticulated elements from all size classes, but large subadults & adult- sized bones dominate These provide strong evidence for social and/or Skeleton: Scott Hartman Other images: NRC Press  Hadrosauridae: Reproduction Ornithopods child-rearing strategies: Not much evidence from basal ornithopods Derived ornithopods (Hadrosauridae) show good evidence of child-rearing and parental care (e.g., Maiasaura, Hypacrosaurus) Nesting sites reused for multiple generations Good evidence for 1 & 2 year juvenile cohorts Natural History Museum, London  Hadrosauridae: Reproduction Hypacrosaurus Nesting Site at Devil's Coulee, AB Creative Commons D. D. Brinkman Brinkman Scott Hartman D. Brinkman Hadrosauridae: Soft Tissue Preservation Edmontosaurus regalis, L. Cret, Grande Prairie, AB Preserves impressions of a soft, fleshy comb Two valid Edmontosaurus species E. regalis (Campanian, W NA) Science Direct E. annectens (Maastrichtian, including AK) Up to 12 m; 4 tons, although some individuals may have got larger Science Direct adrosauridae: Soft Tissue Preservation (Mummie Corythosaurus Public Domain Brachylophosaurus ‘Leonardo’ Public Domain ‘Mummies’ preserve skin impressions & Photos: M Ryan Creative Commons life position of elements; occasionally  Hadrosaurinae: Hadrosaurus foulkii HADROSAURINAE LAMBEOSAURINAE North America’s 1st Dinosaur Skeleton Late Cret. Woodbury Fm, NJ Willian Foulke Joseph Leidy ~8 m long; ~ 2+ tons Collected by William Parker Foulke in 1868 from a marl pit 1st NA dino known from more than teeth Described by Joseph Leidy l images: Public Domain/Creative Commons (U Penn) in 1860; pub in 1865 due to Civil War 1st mounted dino (PANS; osaurinae: Shantungosaurus – The Largest Hadr Shantungosaurus giganticus Late Cretaceous, China Sauropod-sized hadrosaurid! Femur 1.7 m; skull 1.63 m Creative Commons Total length 16.6 m Estimated weight 18 tons Sister taxon to Edmontosaurus from Creative Commons AB Image: David Hone  Lambeosaurinae: Growing A Crest HADROSAURINAE LAMBEOSAURINAE Crests and other soft tissue features were probably used for interspecific signaling D Evans  Lambeosaurinae: Growing A Crest HADROSAURINAE LAMBEOSAURINAE Parasaurolophus Juvenile from the L Cret. Kaiparowits Formation, UT ~ 2.5 m long, ~¼ adult length BASS Adult 14 m) Hypsilophodo Camptosau Iguanodo Parasaurolop Edmontosaur  EVOLUTIONARY PATTERNS IN ORNITHOPODA 4. Social Behaviour Abundant evidence for socially-related adaptations, including: Herding Visual (and possibly aural) displays Species recognition structures Hypsilophodo Camptosau Iguanodo Parasaurolop Edmontosaur