INTRODUCTION
Germain geophysicist and meteorologist Alfred Wegner has concocted a theory of monumental standards insisting on the existence of a continental drift. Mr. Wegner’s theory suggests that about three-hundred million years ago all of earth’s land masses were in a constant state of movement. These masses, we now know today as continents, were collided to form one supercontinent, called Pangea. This Greek word is can be translated to Pan-"all”, Gaia -"earth". In Wegner’s Pangea, Continents South America and Africa are apparently attached to Antarctica. According to the theory, the continents had drifted away from supercontinent into the Continents we have today.
EVIDENCE 1
One of the piece of evidence Wegner provided for this seemingly
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Wegner stated that he found fossils of the same species of plants and animals on different continents. Wegner believes that they could have lived in the same place if the continents had been connected in the past. Some examples of theses ancient fossils are the Mesosaurus, Lystrosaurus, Cynognathus and Glossopteris. The Mesosaurus is a crocodile-like reptile that lived about two-hundred-eighty-six million years ago. They are found solely in southern Africa and eastern South America (see MC p.115 Fig. 11.5 B). It would have been physiologically impossible for this species to swim to between the continents. This fact suggests that Africa and South America were connected at one point. This is the same for the Cynognathus, a mammal type reptile found in both Africa and South America. The Lystrosaurus, a two-hundred-fifty-year-old herbivorous reptile found in South Africa, Antarctica and India. Finally, the Glossopteris was a woody seed-bearing shrub or tree. This plant lived about three-hundred million years ago. It’s fossils were found in Australia, South Africa, India, South America and Antarctica. These ancient spices are not capable of traveling to other continents. It is evident that a supercontinent had been there for these species to live in these continents. Thus, further validating Wegner’s …show more content…
11.5 D). These ice sheets are believed to have existed about two-hundred-fifty million years ago. Wegner has observed scratches on certain rocks, which indicates an existence of ice sheets. These locations at their current positions, would never be able to have ice sheets, given their warm temperatures. Wegner’s supercontinent “Pangea” explains this event. In Wegner’s “Pangea”, these areas are all found towards the South Pole. Also, this supercontinent existed around the same time period as these sheets. Therefore, the existence of ice sheets in such unlikely areas further justifies Alfred Wegner’s “Pangea” and provides evidence that a continental drift has to have
The area composed of the Gander, Nashoba, Avalon, and Meguma Terranes has been extensively studied for many years. However, it was only recently that the terranes were recognized as distinct geologic entities with unique tectonic histories thus there is still much debate regarding the tectonic model which brought these terranes together (Hon et al., 2007). This paper will address the geology of the peri-Gondwanan terranes and propose a potential tectonic model for the accretional orogenic events. It will also primarily focus on the juxtaposition between the Nashoba and Avalon Terranes.
15. The pictures above show how the continents on Earth’s surface have changed position over a very long period of time. What explains this change? (S6E5e, f)
Ŝibrava, V., Bowmen, D.Q., and Richmond, G.M, 1986, Quaternary glaciations in the northern hemisphere; report of the International Geological Correlation Programme, Project 24 (International Union of Geological Sciences and UNESCO): Pergamon Press, Oxford, New York, 514 p.
To set the stage, we must go back 270 million years ago when a majority of the earth’s land masses were collected together in a single continent, a supercontinent, named Pangaea (Encyclopedia Britannica, 1). Historian Alfred Crosby explained that this collected all of earth’s land based biology into a single place, creating a single Darwinian “arena for competition” (Crosby, 1). Or in other words, one big evolutionary pot. Crosby also explains that 180 million years ago, Pangea split into two major land masses, what is now the Americas in the Western Hemisphere as one land mass and Euro-Asia and Africa as the second lass mass (Crosby, 1). What was once a single evolutionary pot, was now two, allowing for plant and animal life to take different evolutionary paths. These two worlds remained relatively separate from each other until the arrival of Christopher Columbus and other European explorers. That contact between the old world and the new world brought two distinct evolutionary arenas crashing into each other and returned a majority of the earth’s landmass into a single Darwinian pot, (Crosby, 1) This was Crosby’s re-knitting of the torn “seams of Pangaea.”
The Old and New Worlds had been separated for millions of years before this voyage (except for periodic reconnections in the far north during the Ice Ages). This period of separation resulted in great species divergence and evolvement. There were still many similar species, such as deer and elm, but Europe had nothing like hummingbirds, rattlesnakes, and hickory and pecan trees. The differences were even greater in the southern hemispheres; the biggest mammal in Africa was the elephant, and the biggest mammal in South America was the cow-sized tapir. Both of these environmental systems struggled for a delicate sense of balance and homeostasis-- but their collision in 1492 began a whole new time of competition and struggle for dominance. The environmental impact of such a collision is enormous and should be looked at as part of our understanding of the Age of Discovery.
Americas by 14,000 ago” (O’Brien 12), after large portions of North America encountered the last ice age, which
How did the Atlantic System affect Europe, Africa, and the Americas? (The Earth and Its Peoples, 500)
Many years ago, continental drift took the Old and New Worlds apart, dividing North and South America from Eurasia and Africa. That disconnection lasted so long that it fostered divergent evolution; for example, the growth of rattlesnakes on one side of the Atlantic. Subsequently 1492, human travelers in part altered this propensity. Their reestablishment of relationships through the merge of Old and New World plants, creatures, and diseases, frequently known as the Columbian Exchange. It’s one of the most spectacular and significant ecological events of the past millennium.
Starr, Chester G., Nowell, Charles E., Lyon Bryce, Stearns, Raymond P., Hamerow Theordore S. A History of the World: Volume II- 1500 to Present. Chicago: Rand McNally, 1960.
The Permian Period was the last period of the Paleozoic Era. During this geological time period’s earlier stages glaciation was extensive. Middle Permian began to warm, and by the late Permian the environment was hot and dry. The environmental conditions were so extreme that the marine and terrestrial life forms were greatly affected. According to research the drastic climate change could have been caused by the formation of Pangaea. In 1912 Alfred Wegener while studying his theory of the continental drift, discovered Pangaea’s very existence. A combination of all of Earth’s landmasses joined together and covered 1/3 of Earth’s surface. Pangaea was f...
The Triceratops was living in the late Cretaceous Era. It lived about 68 to 65 million years ago. The Triceratops were said to live in the Wyoming, Colorado, and Canadian area, where they have cold winters. The Tyrannosaurs dominated all of their prey in North America at that time. Also giant penguin-like marine animals called Polycotylid Plesiosaurs appeared in the oceans towards the south. The Earth was still dominated by dinosaurs at that time. During the late Cretaceous Era, North America was slowly moving westwards, whic...
The Pterodactyl lived during the cretaceous and Jurassic times. Their fossils have been found all over Europe, North America, Australia and
Crosby spans time and space in his work, Ecological Imperialism, making sense of meta-historical time frames from epoch to epoch, from Pangaea to near present, concerning everything from microbes to marinheiros. Crosby’s work stands out in the sea of global histories of European expansion, taking on a far more expansive perspective on the population collapse and role of disease in the conquest of the New World to delve deep into the ecological history of the earth as we know it now, as well as it was in previous geological eras. Crosby places this chapter of human history in a larger biological sphere and navigates across “the seams of Pangaea,” to use his own phrase, to stitch together how European imperialism succeeded due to ecological domination to bring the European ecosystem to head at the expense of native ecosystems and peoples. Crosby argues that Europeans flourished and succeeded in establishing massive oversea empires
Cicadapocalypse (excerpt) Our story begins in the late cretaceous period, the last of the mesozoic era. Dinosaurs are roaming about, minding their own business. A iguanodon here, a pack of velociraptors stalking them nearby. A dreadnoughts there and some triceratops grazing not to far away. However those creatures are not relevant to this tale.
The fourth article I read was, “The Mantle Moves Us.” I noted, because I find it neat, is: instead of riding over the mantle, continental crust might be coupled to it, with the keels anchoring the two together. The upper mantle’s flow would propel the continents in part by pushing on the keels. The fifth, and final article I read was, “What’s Up With the Quakes Before a Volcano Erupts.”