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R E S O U R C E L I B R A R Y A RT I C L E Adventure Science Paleontologist Paul Sereno travels the world to uncover and identify fossils. G R A D E S 8 - 12+ S U B J E C T S Geology, Geography, Human Geography, Physical Geography, Social Studies, World History For the complete article with media resources, visit: http://www.nationalgeographic.org/article/adventure-science/ By Stuart Thornton Friday, January 21, 2011 Paleontologist Paul Sereno’s fossil-finding expedition into Africa’s Sahara Desert in 1993 sounds a lot like the plot of an Indiana Jones adventure movie. With a limited budget, Sereno attempted to lead a team through 1,000 miles of desert, a region plagued by political instability, temperatures of more than 125 degrees, and bands of roving desert pirates. Half of Sereno’s team decided to abandon the expedition. And if that weren’t enough to make the adventure sound like a Hollywood movie, Sereno fell in love with his future wife, who worked as a scribe for the team, over the course of the expedition. When Sereno and his team arrived at their destination, a dinosaur graveyard in the country of Niger, they set about uncovering a group of fossils that would help establish Sereno as one of the most widely known paleontologists in the world. Among the finds were Jobaria, a 70- foot-long plant-eating dinosaur from the Cretaceous period, and Afrovenator, the most complete predatory dinosaur from the Cretaceous that has ever been unearthed in Africa. “It’s the greatest and most challenging expedition I think I will ever lead and accomplish in my life,” Sereno says. Even though Sereno, a University of Chicago professor and a National Geographic Explorer-in- Residence, maintains that the 1993 fossil-collecting mission was his most difficult, most of his international expeditions have been no walk in the park. Around the World In 1988, Sereno traveled to the Ischigualasto badlands, a desert valley in Argentina located in the shadows of the Andes Mountains. Fossils had been found in the region before, but there were no maps depicting where the bones had been discovered. Though he had meager supplies and didn’t speak Spanish, Sereno came back from the trip with the skull and complete skeleton of a meat-eating dinosaur called Herrerasaurus. A second journey to the region yielded the skeleton of the Eoraptor, a 3-foot-long creature that is the world’s most primitive dinosaur. Sereno says these discoveries transformed how scientists viewed the evolution of dinosaurs. The primitive fossils suggest the creatures were evolving while other animals dominated the world 228 million years ago. “These are the most complete dinosaurs from the very dawn of the dinosaur era, when they were just a minor component of the fauna alive,” he says. “They weren’t the biggest. They weren’t the most numerous. But they were dinosaurs. It was a presage to the era when they would take over.” One of Sereno’s biggest finds didn’t happen in the wild, but inside a building in western India. There, in 2001, Sereno helped piece together a collection of fossils found earlier by Suresh Srivastava of the Geological Survey of India and Ashok Sahni of Panjab University. After assembling a skull from the fragments, they named the new find Rajasaurus. “That’s really the first predatory dinosaur that has ever been named in India on the basis of skull reconstruction,” Sereno says. Geography of Fossil-Hunting Having found dinosaurs on five continents (everywhere except Europe and Antarctica), Sereno says using different kinds of maps has been an essential tool for discovering fossils. “It’s really a geographic exercise of combining a topographic [map] over a geologic map,” he says. “That identifies the areas that are plausibly accessible and the age of the Earth that will guide you to the hunting grounds.” The paleontologist, who also discovered the remains of the 40-foot-long crocodile known as SuperCroc, says one of the challenges of leading a team is inspiring others. “You are out there and can instill in the minds of these students the truth of the matter, which is that this is one of a few chances that you have in life to insert a page in the history books— not read a page for the umpteenth million time, but to insert a page,” he says. Sereno compares searching for fossils in the field to being an artist. “You see something sticking out and you have to imagine what it is, the part you can’t see,” he says. “Artists do that all the time.” He admits that though field work can be very exciting, it is only part of being a paleontologist. “There is really three stages: finding something, actually getting it out and back to a laboratory, and then doing the laboratory work and the ultimate science on it,” Sereno says. “Science is about facts and evidence without a doubt, but at its core it is convincing other scientists passionately that you are right,” he says. “That you have discovered something. It can be an idea. It can be a fossil. But you have to convince them of its significance and its importance. That’s science.” Vocabulary Part of Term Definition Speech abandon verb to desert or leave entirely. access noun ability to use. (Afrovenator abakensis) "African hunter"; dinosaur that lived about 135 Afrovenator noun million years ago. Andes noun mountain range extending along the western coast of South America. Mountains Part of Term Definition Speech badlands noun barren area with exposed, eroded rocks. budget noun money, goods, and services set aside for a specific purpose. component noun part. continent noun one of the seven main land masses on Earth. Cretaceous 145 million to 65 million years ago. The period ended with extinction of noun period the dinosaurs and the rise of mammals. crocodile noun reptile native to parts of Africa, Asia, and the Americas. area of land that receives no more than 25 centimeters (10 inches) of desert noun precipitation a year. very large, extinct reptile chiefly from the Mesozoic Era, 251 million to dinosaur noun 65 million years ago. our planet, the third from the Sun. The Earth is the only place in the Earth noun known universe that supports life. (Eoraptor lunensis) "dawn plunderer"; dinosaur that lived about 228 Eoraptor noun million years ago. evolution noun change in heritable traits of a population over time. expedition noun journey with a specific purpose, such as exploration. pre-eminent explorers and scientists collaborating with the National Explorer-in- Geographic Society to make groundbreaking discoveries that noun Residence generate critical scientific information, conservation-related initiatives and compelling stories. fauna noun animals associated with an area or time period. fieldwork noun scientific studies done outside of a lab, classroom, or office. fossil noun remnant, impression, or trace of an ancient organism. study of places and the relationships between people and their geography noun environments. representation of spatial information displaying data about rocks and geologic map noun minerals. graveyard noun site where many bodies are buried. (Herrerasaurus ischigualastensis) dinosaur that lived about 228 million Herrerasaurus noun years ago. Indiana Jones noun series of movies (named after the main character). instability noun state of changing often, usually in unpredictable ways. Jobaria noun (Jobaria tiguidensis) dinosaur that lived about 135 million years ago. Part of Term Definition Speech symbolic representation of selected characteristics of a place, usually map noun drawn on a flat surface. paleontologistnoun person who studies fossils and life from early geologic periods. Paul Sereno noun (1957-present) American paleontologist. pirate noun thief who steals from ships or ships' crews while at sea. plague noun very infectious, often fatal, disease caused by bacteria. plausibility adjectiveseeming to be true, or having the possibility of being true. plausibly adverb possibly true. plot noun story or action of a book or movie. predatory adjectivekilling other animals for food. primitive adjectivesimple or crude. professor noun highest-ranking teacher at a college or university. (Rajasaurus narmadensis) "Regal dinosaur"; dinosaur that lived about 65 Rajasaurus noun million years ago. roving adjectivealways traveling. Sahara Desert noun world's largest desert, in north Africa. scribe noun sharp tool used to make maps using the scribing method. significant adjectiveimportant or impressive. bones of the head, supporting the face and protecting the brain and skull noun upper spinal cord. prehistoric crocodile that lived in Africa and grew to lengths of 11-12 SuperCroc noun meters (37-40 feet). having to do with maps based on natural and human-made features topographic adjective of the land, and marked by contour lines showing elevation. transform verb to change in appearance or purpose. valley noun depression in the Earth between hills. yield verb to produce or result in. Articles & Profiles National Geographic Explorer-in-Residence: Paul Sereno—Paleontologist Audio & Video National Geographic Channel: When Crocs Ate Dinosaurs Websites National Geographic Magazine: SuperCroc Project Exploration Paul Sereno: Paleontologist © 1996–2021 National Geographic Society. All rights reserved..
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  • The Princeton Field Guide to Dinosaurs, Second Edition

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  • A Brachiosaurid Sauropod from the Late Jurassic Can˜ Ado´ N Calca´Reo Formation of Chubut, Argentina

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  • Cranial Anatomy of Allosaurus Jimmadseni, a New Species from the Lower Part of the Morrison Formation (Upper Jurassic) of Western North America

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  • A New Middle Jurassic Diplodocoid Suggests an Earlier Dispersal and Diversification of Sauropod Dinosaurs

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  • Sauropod Dinosaur Remains from a New Early Jurassic Locality in the Central High Atlas of Morocco

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  • Tyrannosaurus

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  • A New Diplodocoid Sauropod Dinosaur from the Upper Jurassic Morrison Formation of Montana, USA

    A New Diplodocoid Sauropod Dinosaur from the Upper Jurassic Morrison Formation of Montana, USA

    A new diplodocoid sauropod dinosaur from the Upper Jurassic Morrison Formation of Montana, USA JERALD D. HARRIS and PETER DODSON Harris, J.D. and Dodson, P. 2004. A new diplodocoid sauropod dinosaur from the Upper Jurassic Morrison Formation of Montana, USA. Acta Palaeontologica Polonica 49 (2): 197–210. A partial skeleton of a new sauropod dinosaur from the Upper Jurassic Morrison Formation (?Tithonian) of Montana is described. Suuwassea emilieae gen. et sp. nov. is diagnosed by numerous cranial, axial, and appendicular autapo− morphies. The holotype consists of a premaxilla, partial maxilla, quadrate, braincase with partial skull roof, several partial and complete cranial and middle cervical, cranial dorsal, and caudal vertebrae, ribs, complete scapulocoracoid, humerus, partial tibia, complete fibula, calcaneus, and partial pes. It displays numerous synapomorphies of the Diplodocoidea, in− cluding characters of both the Diplodocidae (Apatosaurus +(Diplodocus + Barosaurus)) and Dicraeosauridae (Dicraeo− saurus + Amargasaurus). Preliminary phylogenetic analysis indicates that Suuwassea is a diplodocoid more derived than rebbachisaurids but in a trichotomy with both the Diplodocidae and Dicraeosauridae. Suuwassea represents the first well−supported, North American, non−diplodocid representative of the Diplodocoidea and provides new insight into the origins of both the Diplodocidae and Dicraeosauridae. Key words: Dinosauria, Diplodocoidea, Diplodocidae, Dicraeosauridae, paleobiogeography, phylogeny, Morrison Forma− tion, Jurassic. Jerald