BSC1005 Study Guide Chapter 1 Paleontology Dinosaurs everything in bold is important and you must know Paleontologist someone who studies ancient organisms Kids really like dinosaurs because there s a ton of fictional creatures that they love but are sad when someone explains to them that they aren t real When a kid hears that dinosaurs actually did exist well that s just the best thing ever Paleobiology the study of ancient life This includes their anatomy physiology behavior and ecology Dinosaurs were first scientifically recognized in 1842 but people noticed these giant bones sticking out of the ground well before then This includes ancient China and medieval Europe where they were described as dragons that had lived long before In 1676 the femur of a megalosaurus was thought to be of a giant human and named scrotum humanum which is the real first proper scientific name for any dinosaur In England dinosaurs tracks were common but were thought of as huge bird tracks Native Americans in Alberta called them the father of the buffalo others the sacred former giants of the deep past Lewis and Clark Thomas Jefferson was a big fossil collector and asked Lewis and Clark to keep an eye out for more but the two explorers just saw them as remains of large fish People still didn t see these as remains of something extinct They only believed in the existence of animals they had seen Baron George Cuvier proposed these were remains of extinct creatures William Buckland Megalosauraus first scientifically valid dinosaur No one at the time cared Gideon Mantel found a giant creature with teeth like that of an Iguana iguanodon people became excited by the existence of a giant herbivore reptile Richard Owen came to the conclusion that these were a new kind of reptile not previously known and no longer around Called them Dinosauria fearfully great reptiles He listed their attributes as giant upright posture not sprawling and more than two fused sacral vertebrae The reason many of the models so far had not been accurate was the no whole skeletons discovered yet Archosaurians crocs pterosaurs dinosaurs and other Archosaurians like dinosauromorphs 1 Socketed teeth replaced throughout life how we know crocs and gators were related to dinosaurs Pterosaurs and dinosauromorphs closest relatives of dinosaurs and also collectively called Avemetatarsalians hinge like ankles pivot in the middle of the group of bones not between shin and ankle bone Dinosaurmorphs closest to dinosaurs share with dinosaurs erect posture due to in turned ball on femur Key characteristics of dinosaurs 1 3 or more sacral vertebrae fused backbone 2 Hands with three main fingers two in tyrannosaurs and one in alvarezarids 3 Perforate acetabulae the hole in the hip where the thighbone attaches goes all the way through Leidy dinosaurs bipedal like a kangaroo Had first mounted dinosaur s bones but had to break the tail to have it look like it dragged By the 1800s it was discovered there were two types of dinosaurs those with lizard hips and those with bird hips E D Cope O C Marsh and their fossil feud Their rivalry fueled the discovery of a large number of the most famous dinosaurs known today They also theorized the existence of many other dinosaurs thought now to not exist Louis Dollo first Paleobiologist hypothesized that some dinosaurs were herding animals By the late 1800s U S museums got involved and funded own dinosaurs expeditions but after WWI the field slowed down John Ostrom found deinonychus smart small agile and lethal It was a much more avian or mammalian in nature Robert Baker a student of Ostrom challenged many norms in the field and provoked many scientists to research into these fields to prove him wrong As a result of this the field boomed and became a more respected field Chapter 2 the Age of Dinosaurs The very first dinosaurs were small bipedal carnivorous animals that first show up in the fossil record 238 million years ago in the Mesozoic era This time is often referred to the Age of Dinosaurs The Mesozoic era is described into three periods consisting of their own distinctive faunas of dinosaurs and other creatures The Triassic Period occurred 251 200 million years ago The oldest dinosaurs show up midway through this Jurassic Period occurs 200 146 million years ago This was the time of the very largest dinosaurs Cretaceous Period occurred 146 65 54 million years ago the final stage for dinosaurs The bones can be dated using isotopes primarily Uranium 235 which turns into lead 207 Its half life the amount of time it takes for half of the original material to break down spans an appropriate amount of time to age things in millions of years The half life of uranium 235 is 704 million years Climate fossils and isotopes show the climate was much warmer Arid in equatorial regions and like Florida in the middle latitudes The poles were cool wet and rainy like Seattle Plate Tectonics All adjoined into a supercontinent of Pangaea in the Triassic The continents moved apart throughout the Age of Dinosaurs Continental movements are driven by volcanic seafloor spreading in the oceans The continents were close to their current arrangement by the end of the Late Cretaceous This fueled the diversification of dinosaurs on various continents There were no icecaps so there was more water in the ocean so more of the continents were covered with water The flowers of the time were much different from those today and varied throughout the span of the dinosaurs Triassic and Jurassic had low ferns in wetter areas Gymnosperms such as pine trees conifers cypress trees cycads ginkgos etc dominated the world There was less ground cover than there is today Angiosperms flowering plants develop during the Cretaceous and are much more tolerant of disturbances More diverse The world became more vegetated with ground cover all over and closed forests became abundant At this point ground feeding herbivorous dinosaurs also diversified What else lived with the dinosaurs No credible evidence that dinosaurs were even amphibious or fully aquatic Crocodilians the earliest ones were small agile terrestrial predators Some were even bipedal Some ate dinosaurs The deinosuchus was 32 feet long and ate turtles and dinosaurs Turtles the first ones from the Triassic period were terrestrial with teeth Sea Monsters Ichthyosaurs were reptiles that looked and swam like dolphins reaching 40 feet with eyes of a foot in diameter They gave live birth like mammals
View Full Document
Unlocking...