This website uses cookies to ensure you have the best experience. Learn more

The Causes Of The Dinosaurs’ Extinction

1513 words - 6 pages

PAGE PAGE 1 Elizabeth Hoover
Research EssayMay 7, 2013The Causes of the Dinosaurs' ExtinctionAbout sixty five million year ago something happened to change the Earth. At the end of the Cretaceous-Tertiary Period seventy-five to eighty percent of all animal species, including dinosaurs, became extinct. This event is known as the K-T mass extinction because it occurred at the boundary between the Cretaceous (K) and Tertiary (T) time periods. Although there are numerous theories and explanations as to what happened to the dinosaurs, the asteroid theory presented by physicist Luis W. Alvarez in 1981 is today the most commonly accepted. However there are a number of other factors that may have contributed to their extinction.The Asteroid Theory, proposed by physicist Luis W. Alvarez, his geologist son Walter Alvarez and two colleagues at the Lawrence Berkeley laboratory, Frank Asaro and Helen Michel ("Dinosaur" 19), stated that an asteroid four to nine miles wide (10km) made impact with the Earth; this caused dense clouds of dust, ash, and steam to be thrown up into the stratosphere where they cut off the sunlight causing the earth to become dark and cooling it to dangerous levels. Once the Earth became dark and cold the process of photosynthesis stopped, which removed the basic food for marine and terrestrial life. As greenhouse gases became more dominant, temperatures rose well above what they were before the impact. Causing what was left of the dinosaurs who had survived the cold temperatures to become extinct.The Alverez team found evidence in a sixty-five-million-year-old clay sedimentary layer near the K-T boundary in Gubbio, Italy. It gave weight to their theory that the asteroid was the cause of the extinction based on the high levels of the element iridium in the K-T layer. The sedimentary layer had thirty times the amount of iridium in it. The metal iridium, which is similar to platinum, is very rare on Earth's surface but is more common in extraterrestrial objects such as asteroids. They also found the same sedimentary layer with high levels of iridium in New Zealand, Spain, the South Atlantic, the North Pacific, Texas, and Denmark (Fitzgerald 54). To strengthen their theory, the sample layer they collected from Denmark was analyzed and found to not only have high levels of iridium, but also eight other minerals that asteroids are enriched with (Kerr 514).However, the metal iridium was not the only evidence that proves the Alverezs theory. There were also pieces found of once-molten rock, called impact ejecta, which is evidence of an explosion powerful enough to instantly melt bedrock and propel it more than a hundred miles from its origin. Ranging in size from large chunks to tiny beads, impact ejecta are common at or near the Cretaceous-Tertiary boundary.At first there were no craters found that matched the size of the impact the asteroid made. The Alverezs' thought it was possible that the asteroid could have crashed into the ocean,...

Find Another Essay On The Causes of the Dinosaurs’ Extinction

The Extinction of Distinction Essay

682 words - 3 pages Religions‘Why has God forsaken me?’ this is the cryThis is a cry of a man who died on the cross for the cause of god. This is the cry of the mothers whose children have been killed. This is the cry of the fathers looking through the rubble for their loved ones. This is the cry of a girl raped by the soldiers supposedly protecting her. This is the cry of the son dying on a battlefield created for men.And who is listening to this cry?Is

The Extinction of Privacy Essay

1532 words - 7 pages technology and couldn’t wait for the next cell phone to be released. I was always highly interested in what was next, but that was then when I was a young and obvious little kid, now as a young adult in this day of age I have an entirely different feel for all of it; privacy no longer exists and technology is the primary blame. Your identity is unsafe in more places than you may realize. Every store you walk in has the possibility or either

Major Causes of Extinction

1037 words - 4 pages Major Causes of Extinction Hotspots are areas that have rich diversity of species, but many species have become critically endangered because of devastating human activities. The loss of biodiversity in many hotspots was mainly because of habitat loss and fragmentation which in turn have occurred due to pollution, overexploitation of resources, deforestation, increased human population, and introduction of exotic species (Background paper on

Theories Explaining the Demise of the Dinosaurs

1352 words - 5 pages asteroid was so large and landed with such force that it effectively ended the dinosaurs reign over the earth. However, recent evidence and research reported in Proceedings of the National Academy of Sciences suggests that this could not have been the case, because the Chicxulab crater predates the mass extinction by roughly 300,000 years. Rather, the evidence suggests that two or more impacts caused the mass extinction experienced by dinosaurs

The Ethics of De-Extinction

1435 words - 6 pages matter of intact tissue with traces of the animals DNA. Though we cannot recreate dinosaurs, steller’s sea cows, or giant sloths, we can however, re-create a species with close relatives such as the pyrenean ibex, wooly mammoth, thylacine, and the heath hen. Cloning is one of the fastest methods of species revival. After a species has been chosen for de-extinction, we extract DNA from the intact cells; this starts the cloning process. Then we

The Extinction of Fin Whale

1128 words - 5 pages seriously if we want to save its genocide and make their lives secure from illegal hunting. Following are some measures which can be used to save them from extinction: Policy formation: authorities like whale commission and CMS make policies which are strict and clear enough to stop hunting of fin whales. These policies should be having end results of violators of this policy as well as the long term impact of obeying this policy for the

On the Brink of Extinction

1170 words - 5 pages occurrences. A similar study was conducted by Kevin Shear McCann to research the diversity-stability debate. He discovered that one third of the plant and animal species in the United States are now at risk of extinction. Based on this and other devastating accounts, I hypothesized that if the plant biodiversity of a given area is observed over period of time, then the level of diversity will decrease over time due to human intervention and

The Cause of the Dinosaur Extinction

1126 words - 5 pages The Cause of the Dinosaur Extinction The biggest mystery surrounding the dinosaur is how did they die? For over 130 million years dinosaurs ruled the earth. Then 65 million years ago, at the end of the Cretaceous period, they died out. Nobody can really say what actually eliminated the species, although everyone has their very own idea. Asteroid impact, atmospheric changes (hot to cold), catastrophic eruptions and astronomical events

Preventing the Extinction of the Simpona Lemur

2376 words - 10 pages known as the Silky Sifaka lemur, is critically endangered. If treatments of Madagascar’s habitat, specificity the small mountainous area of northeastern Madagascar where the Simpona lemur reside, continue being treated as they are today, this will not only lead to the complete extinction of this rare Lemur, but it will also affect the economic standing in Madagascar as a whole. Therefore, it is vital to recognize the solutions and act on them in

What are the major theories explaining the disappearance of dinosaurs?

807 words - 4 pages Dinosaurs use to cover this earth. Where are they now? Sixty-five million years ago dinosaurs became extinct. The most popular theory as of now is said to be an asteroid theory. Which was the last period of the Mesozoic era? Other theories was said to be a volcanic activities, ice age, disease, change in DNA of dinosaurs cells and even a gradually change in climate. Geologic events also played a role. It is up to me and my team to find out

What Really Killed the Dinosaurs?

885 words - 4 pages Dinosaur stress: Stress on the dinosaurs is a possible solution for their extinction. This theory was first thought up by Heinrch K. Erben when he found that the shell thickness of a certain type of dinosaur species decreased as time went on. It was thought that the warm climate and good habitats in the Cretaceous period could have caused over population of dinosaurs, thus an increase of stress on the dinosaurs would develop. Stress is known to

Similar Essays

The Extinction Of The Dinosaurs Essay

2112 words - 8 pages increase in its levels around the Cretaceous-Tertiary, which is the about the time the dinosaurs went extinct (“Eden Channel”). In conclusion, many theories exist that try to explain and understand the reasons and causes the dinosaurs died out. The more compelling ones including the volcanism extinction theory and the asteroid impact theory. The best evidence and majority of scientists back up these two theories. Right behind those comes the

Extinction Of Dinosaurs Essay

632 words - 3 pages Extinction of Dinosaurs      Two-hundred and thirty million years ago the first dinosaur-like creature roamed the earth. Within five million years it could be considered a dinosaur. They were soon at the top of the food chain. They populated every continent. Then 65 million years ago they vanished. The most powerful creatures ever to live on earth had become extinct.      Dinosaurs

Death Of The Dinosaurs Essay

763 words - 4 pages What happened to the dinosaurs is a highly controversial issue that we still can’t solve to this day. There are plenty of theories about what killed the dinosaurs. Unfortunately, there is a high margin for error due to the fact that it was 65 billion years ago. The most popular belief is an asteroid wiped out the dinosaurs, but how plausible is this theory? In Mexican’s Yucatán Peninsula, there is the 110-mile-wide Chicxulub crater. This

The Einstein Of Dinosaurs Essay

802 words - 4 pages the time of the Tyrannosaurus Rex and other many nasty predators. Using its intelligence along with its ability to hunt at night and survive in cold weather, the Troodon formosus fit in with the dinosaurs of its time. Some scientists think that if the Troodon formosus were to survive the mass extinction of 65 million years ago that it would have evolved into a human type of intelligence (Troodon-The Only Dinosaur That Could Pronounce Its Own Name