The Late Devonian Extinction Research Paper

Stephen Gould’s essay “Sex, Drugs, Disasters, and the Extinction of the Dinosaurs” completely agrees with Joseph Williams and Gregory Colomb’s essay “Argument, Critical Thinking, and Rationality.” Gould’s essay deals with three theories for the extinction of the dinosaurs, two of which he argues are entirely invalid because they are not in accordance with the basic rules of argument laid out by Williams and Colomb in their essay. Gould also states that the third theory of dinosaur extinction, natural disaster, follows all the rules that Williams and Colomb espouse, and thus is a sound argument. Gould, Williams, and Colomb all state that the world has a problem with irrational arguments being shoved down people’s throats, and call for a

The scientists believe that the herbivores ran out of plants, and trees and so all of the herbivores died and after all of the herbivores died, all of the Carnivores died as well. Another theory is that a big asteroid hit the Earth, and the asteroid caused a global extinction.. The final theory that the scientists thought of happening was a disease. Disease may of happened from one dinosaur getting sick and then it just passed on from dinosaur to dinosaur.

8. The periods in which there were mass extinctions are Permian – volcanic eruptions which spewed lava and put CO2 into the air which warmed the climate an estimated 6 degrees Celsius. The resulting of oxygen deficiency. And Cretaceous – asteroid or comet

Shifting from the end of the Permian period 250 million years ago into the next era, the Triassic period occurred between 250 and 199 million years ago and was know for further diversifying life on land. After the Permian period, the Triassic period was largely successful in adapting and evolving, as the world was going through many changes. The land mass known as Pangea began its separation, which would be completed in the Jurassic period. The climate was relatively more severe during this time, with hotter summers and colder winters, but because of the warmer atmosphere, there were no polar ice caps at this time. Towards the center of Pangea, it was mostly a dry desert climate. As for life on earth, most of the marine life had been wiped

In the two essays being discussed we learn that science has a vast range of definitions. Science is the effort to understand (or to understand better), the history of the natural world and how the natural world works with observable physical evidence as the base of understanding. Science is about how the hypothesis is developed and how well it is defended.

The main dinosaurs that died off were Sauropod dinosaurs, long necked, four legged dinosaurs, and stegosauridae, class holding Stegosaurus. Other species that died include ammonites, similar to the living animals called nautilus, many marine reptiles, and bivalves, relatable to modern mollusca. Not much is known about this extinction. It is mainly linked to climate change. So far, no connection to volcanic activity or an asteroid has been made. This extinction gave way to the Cretaceous Period.

It is most likely that a simultaneous occurrence of the different global environmental changes was responsible for ending the Permian period, and the lives of 96% of species. Each environmental issue is a major geological event, and amplified the other events, leading to catastrophic environmental situation, in which barely any life could survive.

<b>Introduction</b><br>Think of a world which existed 290 million years ago. As you look out over the terane in front of you, you think that you are on an alien planet. You see volcanoes spewing ash and lava. Beside them is the ocean which is swarming with many different species of echinoderms, bryozoans and brachiopods. As you look down onto the sea floor you are amazed at the countless number of starfish and urchins. Some animals leave you can't even describe and you have no idea even what phylum they belong to. This is a world at its height in diversity of oceanic species. Millions of wonderous species existed at this time in the ocean and most of them will never appear again in earth's history. In the geologic time scale, a million

Melbourne has a bedrock of Middle Paleozoic age which is included within the Devonian and Silurian periods (354-441 million years prior). These rocks are overlain in wide zones which also include much more youthful rocks, and were generally part of the Tertiary and Quaternary ages (2-65 mya). Rocks of Early Silurian (441 mya) were discovered to be the most established within the bedrock. Particular in the outcrops located in the north-east around Warrandyte (Anderson Creek Formation), and on the west side of Melbourne more specifically the Maribyrnong Valley around Keilor (Springfield Formation). Fossils found within these developments are very unique. Rocks located east of Keilor and south of Warrandyte were discovered to be more youthful, with different ages from Late Silurian (418 mya) in the Melbourne Formation (city region) to Early Devonian (384 mya) at the Humevale Formation (Lilydale).

Just the fact that the Pope has ignored the warnings of Catholic presidential candidates and is trying to fight climate change is monumental. Global warming is a global issue. No matter what religion or ethnicity global warming will affect everyone. Earth is the only known planet capable of supporting life. How embarrassing will it be for our generation if we wipe out life because of our ignorance. Earth has a marvelous ability to rebuild and return to a healthy state. After each of the five mass extinction events Earth was resilient enough to survive and so did life. After the most notorious, the Permian Mass Extinction, less than 4% of life survived. Miraculously Earth rebuilt its ecosystems and was able to sustain life. The causes of the

The initial stage was thought to have been a deadly drop in sea level that led to a loss of habitat stability. The second stage would possibly have been the volcanic eruptions and the release of carbon dioxide into the air causing oxygen levels to decrease. The final stage would possibly have been the rise of the sea levels causing massive floods and destroying near shore habitats. Having all of these three stages at one time would have caused this massive kind of extinction. However, if only one of these stages had happened this extinction would not have been nearly this massive. Studies show that even though this mass extinction may have seemed like a fast-moving process, it took over a million years to

The cretaceous-tertiary (KT) boundary extinction happened approximately sixty five million years ago. Sixty to eighty percent of all living species became extinct at this boundary (Raup 1988). The KT extinction was indeed a mass extinction event. Mass extinctions are periods in Earth's history when extremely large numbers of species die out simultaneously or within a limited time frame. The most severe mass extinction ever occurred at the end of the Permian period when 96% of all species died out. The K-T mass extinction obliterated almost all the large vertebrates on Earth, on land, at sea, and in the air (all dinosaurs, plesiosaurs, mosasaurs, and pterosaurs) suddenly became extinct at the end of the Cretaceous Period. At the same time, most

This final blow would have sent earth into a nuclear winter. According to this theory, dust caused by the asteroid collision disrupted plant growth by blocking out the sunlight needed for photosynthesis for nearly a year. A chain reaction occurred as plants died off, so did the herbivores relying on the plants, and then the carnivores that relied on the herbivores. Around 75% of species became extinct, including dinosaurs, mammals, giant marine lizards, fish, birds, and insects. Meanwhile, seawater flooded around 40% of the world’s continents ("Mass Extinctions").

These techniques led to the discovery of the boundary between the two eras. A single thin layer of clay found within predominantly limestone rocks established this. By comparing the marine life found in, above, and below the clay, the marine life, like the dinosaurs, had been terribly affected by the extinction event. The percentage of life in the upper layers was dramatically lower than that in the lower. This was far more compelling than what was suggested by dinosaur’s fossils.

Rapid climate change also ends up on the suspect list of possible dinosaur extinction events. During the latter part of the Cretaceous Period continents broke up causing volcanoes to erupt and fill the sky with gas and ash resulting in a drastic climate change (“Dinosaurs Climate Change and Biodiversity”). The shifting of continents changed the Earth’s landscape, altering weather patterns and overall climate (“Dinosaur Extinction Theories”). Also, over a long period of time, climate gradually changed. Ocean habits changed, temperatures grew much more extreme causing scorching summers and frigid winters (Norell, Dingus, and Gaffney). Radical temperature changes like these led to a green-house effect, making life for the dinosaurs a lot