NOVEMBER6:Paleobiology of DinosaursDinosaurs includes the largest animals to walk the Earth.Learn in this unit:What is a dinosaur?Where we find them how we study them and what we know about their world.Why the fascination?As children, we get stymied by realization that this is not real (eg. dragons, bunny santa)Paleontologist - someone who studies any aspect of ancient organismsThis course is specifically about paleobiologythe study of the lives of ancient organisms (physiology, behavior, ecology, functional anatomy)The history of dinosaur paleobiologyIt is hard to miss dinosaur bones. Clearly people knew about them before their scientific recognition in1842.China"Dragon Bones" from long dead serpents were unearthed for centuries for medicinal purposes.IN 1676 Giant Human Thighbone found in EnglandLater reinterpreted as the Giant's private parts.The specimen was named Scrotum humanum - technically the first proper scientific name given to adinosaur.Now known to be the end of a dinosaurs`s thigh bone.American Indians referred to Dinosaur remains as the Father of the Buffalo or as a scared former race ofgiants.Lewis and Clark found dinosaur bones in Montana and wrote them off as remains of a giant fish. At that time most people did not think that extinction could occur.Thomas Jefferson (a fossil fanatic) thus told them to be on the look out for mastodons - furry elephants.1770 a 40- foot long sea monster named Mosasaurus was found in Holland.In 1824 William Buckland described a reptile jaw with pointed serrated teeth from England.He called it Megalosaurus "big lizard" since he thought it was just a giant relative of today's lizards.About the same time, surgeon Gideon Mantell of England found giant teeth and bones, Thought it was just a big lizard too.Named it Iguanaodon - Iguana tooth.Giant herbivorous reptiles were unheard of (got a lot of press)Notes: reptiles like lizards and crocodiles have scaly skinRichard Owen took stock of all the crazy giants being found in Europe and noted they were different than the reptiles living today....gianthaving upright posture**named them Dinosauria "Fearfully Giant Reptiles" **QUESTION ON TEST**Own worked with artist Waterhouse to depict them in full size as part of a huge display of British ScienceFamous dinner was held.Owen made several mistakes - all dinosaurs were quadrapedal and he also put spikes on themDino-mania began and hundreds of thousands came to view the Dinosaurs.We now have a better idea of what features characterize them, who they are related to, and whySo what makes a dinosaur a dinosaur?Dinosaurs had teeth in sockets like crocodiles, pterosaurs (flying reptiles) and dinomorphs (dinosaur-likereptiles) thus these are their closest relativesdinosauromorphs have erect posture like dinosaursUnique dinosaur feature 1Three or more sacral vertebrae = fused backbones in hip regionfeature 2Hands with 3 main fingersfeature 3Perforate acetabulae (i.e the hole where the thighbone attached goes all the way through thehip)Yankee DinosaursThe first documented remains were tracks found in 1800.Wrote them off as giant birds.1858 Joseph Leidy given nearly complete skeleton of a duck-billed dinosaurBecame immediately apparent that British were wrong - dinosaurs were actually bipedal!He envisioned it like a kangaroo.New York officials wanted to show up Brits and planned their own exposition in Central Park showing the proper way to mount dinosaurs.Thugs broke in and destroyed them, the dinosaurs are still buried there today!By late 1800s there was enough evidence to show there are two different types of dinosaurs.The "fossil feud" led to the discovery of some of the most famous dinosaurs from the North American west.marsh and Cope found most of the famous dinosaurs seen in museums today.Early 1900s US Museums take over as American DinomaniaAfter WWII most dinosaur hunting slowed downscience was considered kid stuff.most dinosaurs were thought to have been founddinosaurs were only to get the public to come through the gates so scientists could pay for the"important" work on mammals.Dinosaur RenaissanceOstrom discovered Deinonyclaus (need to know this name)Here was an athletic animalOstrom took a student Robert Bakker and said that all dinosaurs were athletic and more like living birdsand mammalsOutcome: everyone started studying dinosaurs and jobs were created, more money is spent ondinosaurs than every before.Nobel Laureate Luis Alvarez and Walter Alvarez in 1980 argued that an asteroid hit the earth and killeddinosaursCladistics:A method to organize physical characteristics of dinosaurs and discern relationships.So all in all dinosaur paleobiology is alive and well and growing we are learning more and more about these animals everyday.NOV8The Age of the DinosaursWhen did dinosaurs live?238 million years until 65.5 million years agoThree divisions to age of dinosaursHow do we know these ages?look at radioactive isotopes in volcanic rocksCompare original amount to final amount to assess agethere were a lot of volcanoes during the age of the dinosaursFor dinosaur age uranium 235 is bestIt is pure when volcano rocks cool. (Carbon dating is too short to be of our use for dinos)We know from the kinds of plants and animals and temp sensitive rocks that:World was warmerIt was arid in equatorial regionslike FL in middle regionsPlate TectonicsContinents move driven by volcanic seafloor spreadingIn the Triassic continents were adjoined - called PangeaBy the end of the Cretaceous they were close to their present positionsOne of the ways we know continents move is by finding species of dinos in different parts of the world.With a warmer Earth there was no ice at the polesThe meant oceans were higher and covered much of the continents and ironically dinos had less land to live on than there is todaySeaways crossed the continents and influenced where dinos could travel - this explains why somespecies are only found in certain regions.Mountain SystemsThe world was fairly flat during the age of the dinosMost of today's mountain ranges had yet to develop to a major extentThe flora during the age of the dinos differed from that of today and the types of plants changed several timesthe types of plants available for forage had a strong influence on what dinos could eatTriassic and Jurassic PlantsThere was less ground to cover back then since there was no grass. Trees had great height and chemical defenses and poor ability to regenerate.By the middle of the
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