Theories on Dinosaur Extinction
What killed the dinosaurs? Several theories have been brought up over time to answer this question. It has been of vast interest to many scientists how creatures the size of the dinosaurs could have been wiped out of existence.
Proposed Theories
Climate Change Theory
Some scientists propose that climate change was killing the dinosaurs before the famous asteroid struck. Fossil evidence shows that the average temperature had dropped from 25 degrees Celsius to 15 degrees Celsius and that the amount of annual rainfall had decreased. Fossil evidence also shows that more than half of the dinosaurs (many large plant-eating dinosaurs), crocodiles, and turtles of the time were gone before the asteroid struck in the Cretaceous period.
The Firestorm Theory
At one point it was thought that an impact from an asteroid combined with volcanic activity would have created mass numbers of firestorms with ground temperatures reaching 1000 degrees Celsius. It was thought that anything that was not destroyed directly from the fires would have died due to blocked sunlight as a result from the soot.
However, new studies have shown that rocks from the supposed time of impact contain little charcoal. In order for it to be possible for the massive firestorms to have occurred, charcoal would have had to have been present in the rocks. Without charcoal there is little likelihood that this theory is true.
Still, some debate that although some investigations claim to have not found charcoal in the rocks, they fail to report that they did find coal. These skeptics claim that coal is not easily distinguishable from charcoal and point out that it is possible that investigators missed signific...
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In Lavoisier’s Memoir in Combustion in General, the author emphasizes the importance of organizing experimental data to form new theories. Specifically, he encourages hypothesis testing and trial-and-error to better understand the laws of nature. Lavoisier apply these principles to his own theory by outlining the observations from combustion and calcification, and by hypothesizing the properities of “pure air” and “the matter of fire”.
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From modern examples and records we know that volcanic activity can set of a chai...
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Throughout Earth’s history there have been many changes. These changes have consisted of temperature fluctuations, atmospheric differentiations, extinctions of various plant and animal life, etc. Over time everything seems to have evolved in some way form or fashion. However, the Permian Era extinction was different from all the rest. This extinction affected every form of life, but especially the marine life. Researchers have stated that 93-97% of all Earths species went extinct during this period of time. This essay will explain how a once blossoming progressive era turned into Earths most catastrophic event.
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seems like it happened so sudden, as geologic time goes, that almost all the dinosaurs
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