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Paleontological Studies Note: Remember you are responsible for graphs, charts and other items that form part of the overall summary of this topic. I) Paleontology A) the study of ancient life and their remains (fossils) 1) fossils (from the Latin fossilium "that which is dug up") are physical remains of past life and its activities preserved in the rock record (a) dinosaur fossils have been found in Mesozoic Era rocks from every continent B) vertebrate paleontology 1) the study of ancient backboned animals, including dinosaurs C) types of dinosaur fossils 1) isolated bones and teeth 2) skeletons, in varying degrees of completeness 3) footprints and trackways 4) skin impressions and feathers 5) mineralized soft tissue (muscles, intestines, organs) 6) eggs (some with embryos) and nests 7) coprolites (fossilized feces) II) “Dinosauria" ("dinosaur") was thought up in 1842 by Sir Richard Owen; from the Greek words “deinos” (meaning fearfully great) and “sauros” (meaning lizard); Sir Owen did not ever state that Dinosauria meant “terrible lizard” A) Owen recognized 3 different dinosaurs 1) carnivorous Megalosaurus 2) herbivorous Iguanodon 3) armored Hylaeosaurus B) Owen recognized that these fossils were different from other fossils and modern reptiles 1) upright limbs 2) extra hip vertebrae 3) other skeletal features C) Dinosauria is now recognized as a single major group of organisms, all descendants of a common ancestor 1) modern definition of Dinosauria (a) all descendants of the most recent common ancestor of Megalosaurus and Iguanodon III) Major dinosaur discoveries A) Britain - Reverend William Buckland 1) Megalosaurus (“big lizard”) (a) formally described it in 1824 (b) thought it to be a giant version of the modern monitor lizard B) Weald region of southern England - Dr. Gideon and Mary Ann Mantell 1) teeth were leaf-shaped, reminiscent of the modern Iguana, a primarily herbivorous reptile 2) called it Iguanodon (“iguana tooth”) 3) formally described it in 1825 4) imagined it to be an immense version of the iguana lizard C) Weald region of southern England – Dr. Gideon and Mary Ann Mantell 1) very large spikes were found arranged along the skeleton (a) first evidence of giant armored reptiles 2) called it Hylaeosaurus (“lizard of the Weald”) described in 1833 3) pictured it as a giant spiky lizard D) Interest in dinosaurs grows 1) 1841 - Sir Richard Owen gives public talks about the fossil reptiles of Britain (a) concludes that Megalosaurus, Iguanodon, and Hylaeosaurus formed their own distinct group (b) proposed the name Dinosauria (“fearfully great lizards”) for this group 2) 1850’s - Great Exposition (a) Benjamin Waterhouse Hawkins sculpted Megalosaurus, Iguanodon, and Hylaeosaurus (and other non-dinosaurs) under Owen’s guidance (b) dinosaurs became popular subjects for popular science, political cartoons, etc. E) Early North American discoveries 1) three toed footprints in the Connecticut River Valley, thought to be giant bird tracks 2) fragmentary skeleton (also from Connecticut), thought to be “Indian skeleton” 3) dinosaur teeth found by explorers in western territories (now Montana) (a) described in 1856 by first American vertebrate paleontologist Joseph Leidy (b) recognized some to be similar to Iguanodon, others to be similar to Megalosaurus, still others to be some sort of lizard F) 1858 - first major North American dinosaur fossil 1) discovered near Haddonfield, New Jersey (a) described by Leidy, who named it Hadrosaurus (“heavy lizard”) (b) teeth and bones were similar to Iguanodon, but fossil was more complete (c) front leg was much smaller and more slender than hindlimb, indicating it was bipedal (two legged) (d) suggested that Iguanodon was bipedal, too G) First recognition of bipedal dinosaurs – 1866 1) New Jersey discovery of bipedal meat-eater described by Edward Drinker Cope of Philadelphia (a) eventually named Dryptosaurus H) Major important rivalry between Cope and Othniel Charles Marsh of Yale University 1) the vast numbers of fossils discovered formed the central collections of major museums and greatly increased the knowledge of extinct life (including some of the first complete dinosaur fossils) I) New discoveries in Europe 1) first complete Iguanodon skeletons 2) first small dinosaurs (Compsognathus, Hypsilophodon) J) Early 20th Century discoveries 1) new, wealthy museums sponsored major expeditions to American west (a) the AMNH and various European museums began the era of imperial paleontology (major expeditions to foreign lands, to bring fossils back to the home institution) (b) most famous AMNH expedition (1) Central Asiatic Expeditions of the 1920s (c) from 1907-1912, German expedition to Tendaguru, German East Africa (now Tanzania) (d) various digs in other parts of the world by other museums (e.g., Germans in Egypt; various U.S. and Canadian museums in Alberta) 2) in the 1920’s, beginning of Great Depression and WWII led to decline in large scale paleontological digs (a) dinosaur science began to lose its scientific appeal K) 1960’s 1) John Ostrom of Yale University (a) reinterpreted horned and duckbill dinosaurs as sophisticated feeders (b) discovered Deinonychus (“terrible claws”) (1) named in 1969 (2) sickle-like claw on foot indicated active leaping predator (3) later comparisons between Deinonychus and the primitive bird Archaeopteryx caused Ostrom to revive idea that dinosaurs were bird ancestors L) 1970’s 1) beginning of the Dinosaur Renaissance (a) new topics of dinosaur research (1) were they cold-blooded or warm-blooded? (2) did they have complex family structures? (3) how did they communicate? (4) how were the different types of dinosaur interrelated? (5) what was the relationship between dinosaurs and birds? (6) how did the dinosaurs go extinct? M) Today 1) Many new discoveries from many parts of the world (a) constant change and updating of information (b) discoveries made from every continent (c) discoveries often done by international teams, included paleontologists from local populations (d) new techniques to find, uncover, prepare and describe fossils
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