Paleontologist someone who studies ancient organisms o Particularly important with regard to scientific literacy since for many children dinosaurs DINOSAURS are their 1st exposure to scientific concepts o History in geology Paleobiology the study of ancient life First accounts of Dinosaur remains o In China dinosaur bones were said to be the remains of dragons first written accounts o Meriwether Lewis found a giant rib bone and said it belonged to an immense fish o The broken end of a large meat eating dinosaur s femur was discovered and interpreted by some to be the remains of giant human s thighbone In England Scrotum humanum was the first proper scientific name given to a dinosaur Important People o Baron George Cuvier was the one to gave serious consideration to the possibility that animals can and have gone extinct o Reverend William Buckland is credited with describing the 1st scientifically valid dinosaur Magalosaurus big reptile but No one cared when it was found o Sir Richard Owen tried to categorize the giant fossil animals of Europe as scaled up members of living reptile groups Named this group Dinosauria fearfully great reptiles Giant Possessing upright stances Non aquatic Having more than 2 sacral vertebrae What the Earth was like at the time of the dinosaurs o The climate was arid in equatorial regions and the poles was cool wet and rainy There was no ice caps at the poles so there was more free water in the oceans and a greater portion of the continents were covered by water o During this time all the continents were together Pangea Plate Tectonics continental movements are driven by volcanic seafloor spreading Dinosaurs came into existence 238 million years and went extinct 65 5 million years ago in the oceans o Uranium 235 breaks down into Lead 207 half life Fossils are best found in Badlands In Sedimentary Rocks o Closest place to go find dinosaurs now are in Georgia Don t know the sex of any dinosaur o Sexual dimorphism difference in size and shape between sexes Iguanodon was the first described herbivorous dinosaur Figure 4 o Made people think dinosaurs were giant lizards Dinosaurs are closely related to crocodiles and pterosaurs closer to pterosaurs o 3 700 lbs is the biggest crocodile bite force that lived with the dinosaurs Plesiosaurs supposed to be the Loch Ness Monster not a dinosaurs a kind of lizards Trace fossil traces of ancient life the primary means by which paleontologists learn about dinosaur biology number 1 means by which we can reveal aspects of dinosaur biology Fossil are any remains of ancient life Type Specimen the all important one used to name describe and serve as future reference for comparison with other specimens All dinosaurs were terrestrial animals Smallest dinosaur is 7 ounces The Deinonychus terrible claw was discovered in Montana o Small large brained and agile with a streamlined body and an enormous flip knife killing o Robert Bakker took these finding and said that dinosaurs were just like birds and animals claw and weren t dumb Dinosaurs 3 key features o 3 or more sacral vertebrae o Hands with 3 main fingers o Perforate acetabulae 2 major groupings of dinosaurs o Ornithischians big hips herbivores Bird shaped hips Beak to crop plants A nutcracker jaw joint Thyreophorans Shield bearers Osteoderms boney shield on their back One of the early Thyreophorans were the Stegosaurous dumbest dinosaurs o Endocasts formed by sediments that in filled the brain cavity during Cerapoda duckbills fossilization and became solidified Gap between front and back teeth Know most about Duckbill dinosaurs Find herds of them bite marks traces mummified coprolites Heterodontosaurs mammal like teeth figure 32 2 sub groups o Ornithopoda Dental Battery hundreds of tightly adjoining teeth self sharpening by distributing tissues 2 types of Hadrosaurs one with a long crest and one without it Some thought the long crest was used as a snorkel but it was disproven because there is no hole o Marginocephalia rim of bone protruding from the back of the skull to shield the neck Has 2 subgroups Function of pachycephalosaurid skulls include Head on butting Flank butting Finite Element model computer modeling the biomechanical performance Ceratopsia horned dinosaurs o Ralph Chapman Andrews Found Oviraptor near nest of what he thought was Protoceratop eggs egg robbers The eggs belonged to the Oviraptor and where protecting their eggs birdlike behavior o The Pachyrhinosaurus had a nasal boss that some believed it was the attachment site for an enormous horn perhaps the largest of any animal figure 45 o Saurischians with pelvis like lizards lizard hips Pubis points forward Long neck Brontosaurus and Apatosaurus are the same one oversplit Largest dinosaur was the Supersaurus which was 140 feet Longer than the auditorium but still in the building Tallest dinosaur was the Sauropseidon which was 56 feet Ornithomimids were the fastest dinosaurs The second major branch of the Saurischian is the Therapoda beast foot Sauropods have nostrils on top of their head Carnivorous teeth Thin hollow bones The 1st known big theropod was the 15 20 foot long ceratosaur Dilophosaurus knife like claw Spinosaurus blown up during WWII The late form of theropods are called ceratosaurs o 4 fingers o Cannibalistic Segnosaurs were probably the only herbivorous theropods Had long claws Trodontids were the smartest dinosaurs the brain of a modern bird Encephalization quotients a measure of brain size relative to body mass Dinosauroid alien like depiction of troodontid in modern day T REX o Didn t drag their tails and only had 2 fingers o CT scans of T Rex skull shows that they had a great sense of smell and vision o Couldn t run but where amble o Had cannibalistic behavior o Scavenger Predator Debate Track marks are the primary resource in this debate Not known if T Rex was more a predator or scavenger Most evidence for them being a predator The late 1960 s signaled a new era in dinosaur research with a strong emphasis on the lives of these animals the dinosaur renaissance o Not just like living reptiles but they were not exactly like birds and mammals either o Discovered they didn t drag their tail o Still not sure what the metabolism of dinosaurs was like Shows a mix of both reptilian growth lines and avian mammalian highly vascularized attributes o The highly vascularized nature of their bones suggests these animals grew extremely fast like birds for part of the year but such growth came to a
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