volcano-greenhouse theory. <br> <br><b>Details of the Impact Theory</b> <br><li>In the mid-late 1970s‚ Luis Alvarez and his impact team began searching for the cause of the K-T extinctions. <br><li>His evidence of impact was enrichment of the chemical‚ iridium‚ in a thin layer of clay a few centimenters thick at the K-T boundary. His original theory held that a giant asteroid struck earth 65 million years ago‚ blasting so much dust into the atmosphere that it blocked out sunlight‚ and plunged earth into
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Stephen Jay Gould‘s (2002) essay: Sex‚ Drugs‚ disasters‚ and the Extinction of Dinosaurs‚ investigates dinosaur extinction theories. According to Gould‚ scientific conclusions are the consequence; not the essence. Gould believes science’s main problem is the failure to separate fascinating claims from the scientific methods used‚ stating that “…science is‚ basically‚ a way of knowing” (pg.267). Gould examines three proposed ideas of dinosaur extinction. They are sex‚ drugs‚ and violence. Since
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this event was caused by climate and geological changes that interrupted the dinosaurs’ food supply. However‚ in the 1980s‚ father-and-son scientists Luis (1911-88) and Walter Alvarez (1940- ) discovered in the geological record‚ a distinct layer of iridium (an element found in abundance only in space) that corresponds to the precise time the dinosaurs died. This suggests that a comet‚ asteroid or meteor impact event may have caused the extinction of the dinosaurs. In the 1990s‚ scientists located the
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amount of evidence. In 1980‚ Walter Alvarez of the University of California at Berkeley discovered deposits of iridium in sediments that dated back from the Cretaceous period‚ which was when the mass extinction occurred. "Iridium is rare on earth‚ but is concentrated in meteors and comets" ("mass extinction").This led to proposal of the asteroid theory since the discovery of the iridium sediments proves that an asteroid had hit earth. Then in 1991‚ the Chicxulub crater was found on the Yucatan peninsula
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1. Before you read‚ decide which of three explanations for the extinction of the dinosaurs you like best. Write an explanation of why you like it. Sex: Testes function only in a narrow range of temperature. (Those of mammals hang externally in a scrotal sac because internal body temperatures are too high for their proper function.) A worldwide rise in temperature at the close of the Cretaceous period caused the testes of dinosaurs to stop functioning and led to their extinction by sterilization
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INTEGRATION Similar cases have made us understand that the willingness/unwillingness of firms to exploit IT capabilities could have significant effects. 1- The Crisis at Encyclopedia Britannica We would recall the refusal of Britannica to partner with Microsoft on a multimedia CD-ROM version of the encyclopedia‚ owing to its “traditional way of selling. They regarded an IT initiative that would have reduced the cost of printing encyclopaedias as one that would ‘both cannibalize revenue and reduce
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vacation. Iridium was the venture that Motorola invested in. They basically invested half a billion dollars into this venture and it concluded that the service was too expensive because there were very few people using it as the connection was very poor. The cellular phone market was very successful and while the idea of phones that could work anywhere on earth was good for people in rural areas‚ there were not enough people living in these remote areas to make it a profit making business. Iridium filed
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article is plausible‚ but some of these concepts‚ may not provide enough evidence to conclude the argument‚ but one idea stands out the meteor impact. With the meteor impact‚ a chemical was found‚ iridium‚ which is not indigenous to certain areas on Earth. Coincidently the meteor had high concentrations of iridium causing a spark in interest for the science community‚ unlike the other two. Studies cannot be conducted on any of the dinosaur’s fossils to prove whether or not they over-heated or over-dosed
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Chapter 3: The Marketing Environment |What’s Ahead | |The Company’s Microenvironment | | |The Company | | |Suppliers | | |Marketing Intermediaries | | |Customers | | |Competitors
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1.) Were the North American megafauna wiped out by early human colonizers? The Overkill hypothesis is of the Clovis crossing into a “virgin continent” (The America’s) and wiped out the megafauna due to overhunting. First developed by Paul Martin in the 1960’s‚ Clovis started to occupy North and South America 13‚500-12‚500 years ago; soon after early sites were established 17 genera of North and South American megafauna went extinct between 13‚250-12‚900 (other species such as ground sloths become
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