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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The possibility if a meteor strike as the cause of extinctions is discarded, something that most specialists agree on. There is no evidence of any meteor crater big enough or recent enough to be accountable for it; there are no “elements that are common extraterrestrially but less so on Earth, such as iridium, and no sign of a tsunami or other phenomena following the impact.” The extinctions where also very selective and occurred over a very long period of time. If a “one shot” catastrophe had been the cause it would have affected all species at the same time and in similar
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”.
The question of what caused the extinction of megafauna during the Late Pleistocene period is one that archaeologists have struggled to answer for decades, but why should it matter? Discovering with certainty the cause of megafaunal extinction would simultaneously prove or disprove any of the proposed implications of each existing theory regarding this massive extinction.
...ruel journey towards a true self-revelation of herself. Starting with her teen years, she was hassled by her Grandmother to marry for stability and money, not love. She would then follow a man with a big voice to escape the laborious and unaffectionate life with Logan to marry Jody. Realizing that Jody was an even bigger nuisance for a much longer period of time, she would then go on to marry Tea Cake. Janie has returned to her own place, as her own woman, with her own memories to guide and comfort her. Although she grieves Tea Cake's unfortunate death, she has come back a wiser person and is stronger because of it. She will keep Tea Cake alive in heart to keep her company and live joyfully in the next stage of her life knowing that Tea Cake helped her realize her capacity to mature into a loving adult and actually love a person to the fullest extent possible.
...out what is for her and how she wants to live. So in the end, she is where she wants to be. Janie pulls in the horizon that she has spent her whole life searching for. She calls her soul to come in and see. Where once her soul was separate from her, it is now a part of her. Janie grew throughout the novel into a strong and independent woman. Although Janie cared for Tea Cake, she needed to kill him in order to keep him from suffering. Janie shows the reader that she has lived her life fully the way she wanted too and is now able to die having no regrets in life. Although Janie did recognize that most men were obsessed with power and thrived for complete control, she did discover a man who helped push her to her goals. Tea Cake helped Janie a lot, but he made sure she did not rely on him because from the moment they met, he knew how strong of a woman Janie truly was.
In the end, Janie found herself being defined by other people, so to say Logan, Joe, and Tea Cake. During her marriage to Logan, Janie is viewed as a spoiled and non-hard working girl that needs to learn what it means to make a living. In her marriage to Joe, Janie is only needed for her outward appearance for him to define as his possession; never did he consult her about what she wanted. In both of these relationships she was forced to be something that she was not. Once Tea Cake came along everything had changed; going from following another man’s orders to being able to live a fun-loving life. Throughout the time she spends with him, finally free from being defined by someone else, Janie Crawford discovers who she is and what love is.
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.
...r optimum temperatures, hot climate caused the dinosaurs to heat up beyond their optimum. However, the heat didn’t kill them, but sterilized the males, because their testes functioned at certain temperatures. Gould argues that this theory is untestable, and the experiments with the influence of extreme temperatures on modern alligators do not necessarily explain the extinction of dinosaurs. Furthermore, many questions are not answered because of the absence of evidence. Gould states that this theory is another example of bad science.
...me 300,000 years after the impact. We still don’t know for sure what happened to the dinosaurs, and there is a possibility that we never will know. However, several signs indicate that the Chicxulub asteroid probably created conditions that begin the decline of the dinosaurs. This was most likely followed by a second large impact, or several smaller impacts that caused drastic changes in the environment and resulted in the mass extinction.
War is a patriotic act where one seeks the determination to lead their country. It can be viewed noble, cruel, inhumane and can make an individual a hero or a criminal. It effects everyone in a society, hoping their loved one is safe whether fighting in the trenches or waiting at home. It has led to severe individuals suffering from posttraumatic stress disorder. Two poems in war literature “Anthem for Doomed Youth” by Wilfred Owen and “Facing it” by Yusef Komunyakaa, the authors’ different perspectives will be presented. Owen portrays war as a horror battlefield not to be experienced and the glorious feeling to fight for one’s country. Komunyakaa on the other hand shows an African American that serves in Vietnam War and visits the Vietnam Veterans Memorial Wall. The poets’ choice of diction, setting of battlefield and various uses of poetic devices create a desired effect.
He is Janie's real first love, and is finally happy with him. Tea Cake was the most contrasting between the husbands because he allowed Janie to discover her voice and be herself again. He let her do things that women of the time weren't allowed to do normally because he believed she was equal. He loved Janie for herself and nothing less. Their relationship was not based off material things. All three husbands hit Janie but Tea Cake was the only somewhat justified one because Janie did not mind it. She was using her old relationships come into play by not saying anything, just like she did for the last two. In the book it says, “Janie awoke the next morning by feeling Tea Cake almost kissing her breath away. Holding her and caressing her as if he feared she might escape” (107). Janie cannot help but think about Tea Cake and how much she loves him. He stand for the feeling of happiness that Janie had always dreamed of. Janie finally realizes what love is. They listen to each other and treat one another as equal
From modern examples and records we know that volcanic activity can set of a chai...
seems like it happened so sudden, as geologic time goes, that almost all the dinosaurs
The Jurassic period is known as one of the most interesting periods of time in earth’s history, mainly for the awe-inspiring creatures many of which have gone extinct, the most remarkable being the dinosaurs. Life in the ocean during this time was also extremely diversified and amazing for the creatures it beheld. The Jurassic occurred from 199.6 to 145.5 million years ago, following the Triassic Period and preceding the Cretaceous Period within the Mesozoic Era. The supercontinent of Pangea began to drift apart during this time. Right before the Jurassic period began, a major extinction event occurred wiping out much of the life on earth. The events that unfolded afterwards gave life to a new planet.