miércoles, 11 de junio de 2014

Homework 16th - 20th June

Due Tuesday 17th - Please read the attached article and write a personal essay. remember that a personal essay is a piece of writing that addresses a given topic from the writer's own perspective, usually including some examples from the person’s life to support the main ideas. Use approximately 150 words.


The Sixth Species Extinction can Still be Avoided

Source: Natural News ( BBC News)
 
(NaturalNews) Human beings, having reached the 6.7 billion mark, have succeeded in modifying our environment to the point of harming the biodiversity of a wide variety of native species. We are even at the point now that our own long-term survival is in question. The earth has endured five major extinctions in the four billion years it has existed. The first occurred 450 million years ago, shortly after the evolution of the first land-based plants. Four more extinctions occurred over the time between then and now and this brings us to the point of the sixth extinction. The sixth extinction is likely occurring RIGHT NOW and we are the root cause of it.

The International Union for Conservation of Nature keeps track of over 41,415 species to formulate an annual "red list." It is estimated that 16,306 of the 41,415 are threatened. What will happen to this species decline when our planet population hits 9.3 billion (predicted for 2050)? Unless several radical changes are made the decline is likely to intensify.

American biologists Paul Ehrlich and Robert Pringle present their opinion in the August 12th Proceedings in the National Academy of Sciences. A special section is devoted to the sixth extinction. These two researchers state that, "The fate of biodiversity for next ten million years will almost certainly be determined in the next fifty to one hundred years by the activity of a single species. That species, Homo sapiens, is about 200,000 years old." They continue on to compare humans to a "spoiled teenager," who is mistreating the ecosystems that "produced us and support us, mindless of the consequences."

Life dates back 3.7 billion years. It was not until 500 million years ago and the explosion of the Cambrian that the first complex marine organisms appeared, though. Since then five great extinctions have occurred.

The first
extinction occurred 440 million years ago and caused the disappearance of 65 percent of all species. This was caused by significant glaciations that were followed by warming and this provoked big changes in sea levels.

The second extinction occurred 380 million years ago and caused the death of 72 percent of mostly marine
species. This catastrophe was due to a global chilling and the fall of several meteorites.

The third extinction occurred 250 million years ago and was so huge that life almost didn`t recover. Approximately 90 percent of all species disappeared. The causes of this catastrophe are still being debated, but some believe that big lava flows in Siberia (perhaps provoked by an asteroid) changed the climate and reduced the amount of oxygen present in ocean waters.

The fourth extinction occurred 200 million years ago and is associated with the opening of the Atlantic Ocean and large lava flows that warmed the climate. Approximately sixty-five percent of all species died.

The fifth extinction occurred 65 million years ago and is the one most people are familiar with because it is associated with the disappearance of the dinosaurs and 62 percent of all species. The probable cause was an asteroid fall in the Gulf of Mexico and significant lava flows in India.

More recently, during a period from 50,000 to 3,000 years ago, approximately half the great mammal species disappeared. Some researchers consider this to be the sixth extinction and believe the extinction due to human behavior has already begun.

Humans must change the way we look at nature. It is necessary that we master demographic expansion and begin to drastically reduce our excess consumption of important
natural resources. The root of much of our consumption is the desire to satisfy excessive tastes and not necessary needs. Bringing our consumption back into a more moderate level instead of always striving for bigger and better is a key to reducing consumption. Our use and exposure to media is intricately connected to consumption levels. If one`s use of the many forms of media is reduced, a reduction in excessive consumption will naturally follow.

Another important area to consider is the services that the earth offers us. Our earth provides an amazing bounty of raw materials, perfectly natural water filtration, natural carbon storage facilities in vast forests, natural prevention of erosion and floods by vegetation, and natural plant pollination services furnished by insects and birds. The entire world would be wise to evaluate the value of these perfect services nature is providing us and take steps to assure these services are protected. Wasting and squandering what we have been given is a serious mistake.

Paul Ehrlich and Robert Pringle propose that we appeal to private foundations that are dedicated to conservation. This approach is less expensive for the taxpayer and also enables significant money to be generated.

Another worry the two researchers share is about the growing separation in industrialized countries between the population and nature. This separation is largely due to intensive multimedia use. They have seen a correlation between the rise of electronic media and a significant reduction in visits to national parks. Similar situations have occurred in other developed countries as well.


Learn more:
http://www.naturalnews.com/024897_extinction_natural_consumption.html##ixzz34N7fhpt2