...Era was known as the "Age of Marine Life." This "Age of Marine Life" all began with what is called the "Cambrian Explosion." The "Cambrian Explosion" happened roughly 542 million years ago and obviously took place during the Cambrian Period. It was when most of the major groups of marine animals appeared in a relatively short period of time. According to fossil records, Bryozoa, algae, sponge (porfera), Arthropoda (trilobita), Mollusks (plecypoda, gastropoda, cephalopoda), and corals first appeared all in the Cambrian Period. The Ordovician Period followed the Cambrian Period, and this is when some of the first brachiopods appeared, such as clams, snails, and cephalopods. Also, ostracoderms, jawless armored fish, were the earliest vertebrates that appeared in this time period. "Typical Ordovician fish had large bony shields on the head, small, rod-shaped or platelike scales covering the tail, and a slitlike mouth at the anterior end of the animal" (www.ucmp.berkeley.edu). During the Silurian, there was a widespread radiation of crinoids, a continued proliferation and expansion of the brachiopods, and the oldest known fossils of coral reefs. There was also the appearances the first known freshwater fish. And finally, the first record of life on land! Fossil records show a group of fungi on land, and also arachnids and centipedes. According to www.ucmp.berkeley.edu, "Most Silurian plant fossils have been assigned to the genus Cooksonia, a collection of branching-stemmed...
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...generation regards the possibility of a forthcoming, human-induced mass extinction event and what it’s effects would be upon the evolution rate of species. In the search for understanding this possibility and its effects, scientists must look to the past where it is widely accepted that there have been 5 previous periods of mass extinction. The term ‘mass extinction event’ is defined as any period when abnormally large numbers of species die out simultaneously or within a limited time frame. Such occurrences have been observed at 5 places in history- the Ordovician-Silurian, Late Devonian, Permian, Triassic Jurassic and Cretaceous periods. What was the cause of these extinction periods? Well... no one can say for sure. Although there are a number of plausible hypotheses, the sheer amount of time and space between today and the events in question makes it very difficult to place a theory as anything more than conjecture. In saying this, it is known that these cataclysms were random occurrences and not caused by the actions of any one single species. The extinction of species is not normally considered an important element of Neodarwinian theory, in contrast to the opposite phenomenon, speciation. In the wake of mass extinction periods, the fossil records provide an accurate and reliable source of information invaluable to the study of evolution. Today, there is evidence mounting to suggest that the sixth mass extinction may be beginning- but the apocalypse this time is us. Human activities...
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...Geologic Background: PALEOZOIC: The Paleozoic era was is the earliest of the three geologic eras and spans from about 542 to 251 million years ago. Numerous events that significantly impacted the overall structure of the earth took place during this time period. The Paleozoic Era is divided into six different subcategories which include: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian. Early in the Paleozoic the continents were far apart but moving tectonic plates caused continents to move together into one large continent called Pangaea. Some of the significant geologic events that occurred during the Paleozoic era includes the evolution of a large number of animals, some of which are distant ancestors to modern organisms, between 530 and 520 million years ago. Also during this time period, there was an introduction to animals without backbones (invertebrates). Organisms such as corals, brachiopods, mollusks, and arthropods populated the early and middle parts of the Paleozoic era. A massive extinction event known as “The Great Dying” marked the end of the Paleozoic era. During this mass extinction, as many...
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...pieces, with one large piece detonating about 34 km above the surface, and a second, much larger piece detonating at an altitude of approximately 21 km” (Tagliaferri, 1998). Scientists were lucky to record this data via satellite to study the force an asteroid can have when impacting firsthand. There is evidence of asteroid impacts covering the surface of the earth and other surrounding planets in space. There are also many theories involving asteroid impacts causing mass extinctions on Earth, the most common being the extinction of the dinosaurs 65 million years ago (deGrasse Tyson, 2005). Most of the impact evidence shows that the earth has been attacked by these asteroids since its formation billions of years ago. Evidence all around us tells us that the Earth will be struck, and another major asteroid impact will occur. The most common and highly argued impact event is the one that may have wiped out the dinosaurs. This event in itself has many theories, but the one common element in most sound dinosaur extinction theories is that a major impact event occurred around the same time the dinosaurs stopped roaming the Earth. Most of the scientific community agrees that an asteroid impact did destroy the dinosaurs. Some scientists; however, claim that the dinosaurs were dying off well before the asteroid strike, due to climate changes, and that the impact only “finished them off” (Archibald, 2005). This very well could be...
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...BROCK UNIVERSITY Final Examination Course: ERSC 1F90 Date of Examination: April 21, 2011 Time of Examination: 19:00-22:00 Number of Pages: 7 Number of Students: 468 Examination Time: 3 hours Instructor: Hess No examination aids other than those specified on the examination script are permitted. NO TEXTING!!! Use or possession of unauthorized materials or use of any device other than those specified will automatically result in the award of a ZERO GRADE for this examination. This means you should not have your mobile device out for ANY REASON!!! 1. 2. Answer ALL questions on the provided SCANTRON sheet. Please use a pencil. Turn in the question sheet AND SCANTRON sheet at the end of the examination. ######### Name ________________________ -P~.d. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. as + 1. The positive feedback mechanism in which a population falls below a threshold level, mutations proliferate due to reduced genetic diversity, and the population is further reduced is called: A) inbreeding depression B) toxic genetics C) environmental resistance D) dieback 2. About how much solar radiation is reflected back by the atmosphere of our planet? A) 25% B) 85% C)3% D) 5% 3. The correct order for layers of the atmosphere, from the top to the ground surface, is as follows: A) thermosphere, stratosphere, mesosphere, troposphere B) troposphere, stratosphere, mesosphere, thermosphere C)...
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...Dinosaur extinction is still a major mystery of earth history. In this review article, extinctions in the geological record will be briefly mentioned. Many of the imaginative theories for the extinction of the dinosaurs will also be presented. Within the uniformitarian paradigm, the meteorite impact theory, once considered ‘outrageous’, now is the dominant theory. However, the volcanic theory is still believed by a majority of paleontologists. Both theories have their strengths and weaknesses. The unscientific behavior of those involved in the meteorite paradigm change will be briefly explored. Evidence that the dinosaurs died in a cataclysm of global proportions will be presented, such as the huge water-laid dinosaur graveyards found over the earth. Occasional nonspecific bone-beds and the rarity of fossils of very young dinosaurs suggest a catastrophic death and burial. The billions of dinosaur tracks recently discovered provide testimony to unusual, stressful conditions. Nests, eggs, and babies are a challenge to a Flood model, but there are enough unknowns associated with the data that solid conclusions are difficult to draw. The part that impacts and volcanism play in a Flood paradigm will be briefly discussed. The question of whether the K/T boundary and the extinction of the dinosaurs should be considered a synchronous event within the Flood will be considered. Introduction Dinosaurs bring wonder to children and adults alike. That such great beasts once roamed the earth...
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...• English/US • Answers • Store • Outreach • Media • Kids • Education • Donate • Answers in Genesis • Answers • Animals • Dinosaurs • Dinosaur Extinction • The Extinction of the Dinosaurs The Extinction of the Dinosaurs by Michael J. Oard on August 1, 1997 Share: • • • • Originally published in Journal of Creation 11, no 2 (August 1997): 137-154. Shop Now First published: TJ (now Journal of Creation) 11(2):137–154 August 1997 by Michael J. Oard Dinosaur extinction is still a major enigma of earth history. In this review article, extinctions in the geological record will be briefly mentioned. Many of the imaginative theories for the extinction of the dinosaurs will also be presented. Within the uniformitarian paradigm, the meteorite impact theory, once considered ‘outrageous’, now is the dominant theory. However, the volcanic theory is still believed by a majority of palaeontologists. Both theories have their strengths and weaknesses. The unscientific behaviour of those involved in the meteorite paradigm change will be briefly explored. Evidence that the dinosaurs died in a cataclysm of global proportions will be presented, such as the huge water-laid dinosaur graveyards found over the earth. Occasional monospecific bone-beds and the rarity of fossils of very young dinosaurs suggest a catastrophic death and burial. The billions of dinosaur tracks recently discovered provide testimony to unusual, stressful conditions. Nests, eggs, and babies...
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...evidence for this hypothesis was published in Darwin’s Origin of Species one year later, the appearance of which provoked other leading scientists like August Weismann to adopt and amplify Darwin’s perspective. Weismann’s neo-Darwinian theory of evolution was further elaborated, most notably in a series of books by Theodosius Dobzhansky, Ernst Mayr, Julian Huxley and others. In this article we first summarize the history of life on Earth and provide recent evidence demonstrating that Darwin’s dilemma (the apparent missing Precambrian record of life) has been resolved. Next, the historical development and structure of the “modern synthesis” is described within the context of the following topics: paleobiology and rates of evolution, mass extinctions and species selection, macroevolution and punctuated equilibrium, sexual reproduction and recombination, sexual selection and altruism, endosymbiosis and eukaryotic cell evolution, evolutionary developmental biology, phenotypic plasticity, epigenetic inheritance and molecular evolution, experimental bacterial evolution, and computer simulations (in silico evolution of digital organisms). In addition, we discuss the expansion of the modern synthesis, embracing all branches of scientific disciplines. It is concluded that the basic tenets Dedicated to Prof. Dr. Dr. hc mult. Ernst Mayr on the occasion of his 100th birthday U. Kutschera ()) Institut für...
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...Answers to Conceptual Integrated Science End-of-Chapter Questions Chapter 1: About Science Answers to Chapter 1 Review Questions 1 The era of modern science in the 16th century was launched when Galileo Galilei revived the Copernican view of the heliocentric universe, using experiments to study nature’s behavior. 2 In Conceptual Integrated Science, we believe that focusing on math too early is a poor substitute forconcepts. 3 We mean that it must be capable of being proved wrong. 4 Nonscientific hypotheses may be perfectly reasonable; they are nonscientific only because they are not falsifiable—there is no test for possible wrongness. 5 Galileo showed the falseness of Aristotle’s claim with a single experiment—dropping heavy and lightobjects from the Leaning Tower of Pisa. 6 A scientific fact is something that competent observers can observe and agree to be true; a hypothesis is an explanation or answer that is capable of being proved wrong; a law is a hypothesis that has been tested over and over and not contradicted; a theory is a synthesis of facts and well-tested hypotheses. 7 In everyday speech, a theory is the same as a hypothesis—a statement that hasn’t been tested. 8 Theories grow stronger and more precise as they evolve to include new information. 9 The term supernatural literally means “above nature.” Science works within nature, not above it. 10 They rely on subjective personal experience and do not lead to testable hypotheses. They lie outside...
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...62118 0/nm 1/n1 2/nm 3/nm 4/nm 5/nm 6/nm 7/nm 8/nm 9/nm 1990s 0th/pt 1st/p 1th/tc 2nd/p 2th/tc 3rd/p 3th/tc 4th/pt 5th/pt 6th/pt 7th/pt 8th/pt 9th/pt 0s/pt a A AA AAA Aachen/M aardvark/SM Aaren/M Aarhus/M Aarika/M Aaron/M AB aback abacus/SM abaft Abagael/M Abagail/M abalone/SM abandoner/M abandon/LGDRS abandonment/SM abase/LGDSR abasement/S abaser/M abashed/UY abashment/MS abash/SDLG abate/DSRLG abated/U abatement/MS abater/M abattoir/SM Abba/M Abbe/M abbé/S abbess/SM Abbey/M abbey/MS Abbie/M Abbi/M Abbot/M abbot/MS Abbott/M abbr abbrev abbreviated/UA abbreviates/A abbreviate/XDSNG abbreviating/A abbreviation/M Abbye/M Abby/M ABC/M Abdel/M abdicate/NGDSX abdication/M abdomen/SM abdominal/YS abduct/DGS abduction/SM abductor/SM Abdul/M ab/DY abeam Abelard/M Abel/M Abelson/M Abe/M Aberdeen/M Abernathy/M aberrant/YS aberrational aberration/SM abet/S abetted abetting abettor/SM Abeu/M abeyance/MS abeyant Abey/M abhorred abhorrence/MS abhorrent/Y abhorrer/M abhorring abhor/S abidance/MS abide/JGSR abider/M abiding/Y Abidjan/M Abie/M Abigael/M Abigail/M Abigale/M Abilene/M ability/IMES abjection/MS abjectness/SM abject/SGPDY abjuration/SM abjuratory abjurer/M abjure/ZGSRD ablate/VGNSDX ablation/M ablative/SY ablaze abler/E ables/E ablest able/U abloom ablution/MS Ab/M ABM/S abnegate/NGSDX abnegation/M Abner/M abnormality/SM abnormal/SY aboard ...
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