Organisms And The Non Living Environment example essay topic

Rachel Carson's Silent Spring begins with a short story depicting a made-up town in the heart of America where all life once lived in harmony with its surroundings. Carson quickly presents her central issue by quickly describing the disasters this made-up town faces. Because what silenced the made-up town was the inhabitants and their ignorance to the environmental hazards they had imposed as a result of their decisions. Although the town does not exist, the potential of the occurrence of these disasters is an eye-opener for the reader, as well as a great lead in for the book. A re occuring theme in biology, life is a result of the interaction between living things and their non-living environment.

However, this balance is disrupted when the non-living environment is contaminated by dangerous materials. Carson states that since the 1940's over 200 basic chemicals have been created for killing insects, weeds, rodents, and other organisms considered pests by our society. The introduction of such chemicals into our environment have caused an unmeasurable amount of damage. The environmental damage caused by a pesticide must be measured in the totality of life forms it affects, ie., along the entire food chain. Sprays to kill mosquitoes accumulate in fish, in fish-eating birds, and in mammals eating birds and fish (including man! ).

Today's insecticides are no match to the in organics and the Arsenical's used before World War I. Of these, the most widely used can be classified as either DDT or the organic phosphorus insecticides. DDT is a chlorinated hydrocarbon. Many believe this pesticide is harmless because there have been a substantial number of people that have come in contact with teh chemical and have suffered no physical damage. But the truth is that DDT is very harmful. Although the harmful properties of the chemical is not seen immediately, its damaging characteristics become measurable as the chemical is passed on from organism to organism through the food chain; becoming more and more harmful with each transfer. Long term exposure to pesticides may result in the gradual accumulation of a lethal dose.

While the residue at the time of application may be within an acceptable tolerance, fat-soluble compounds may continue to accumulate in body fat and in substances like milk to very high levels. These chlorinated hydrocarbons were directly responsible for tremendous environmental damage. Several species of birds were driven to near extinction before the full impact of the insecticide was realized. As for Phosphorus insecticides, there are obvious hazards.

This chemical is known for its acute poisoning of people such as people who spray it or people that may come in contact with it through drifting spray comming from vegetation coated with it. By destroying enzymes in the body that perform specific functions, the physical harm done to the person is very quickly. To workers dealing with teh chemical, the danger has become serious. As a result of teh dangers, certain states have established labs in which workers dealing with the chemical can be tested and receive an accurate diagnosis from expert researchers. Along with the potential to harm living organisms, the pollution of the non-living environment, which is equally important in the interaction responsible for the emergence of life, is also discussed by Carson.

The consequences of surface and ground water contamination can act as carriers for the fatal pesticides. Although nature's purifying properties can potentially mend an amount of the damage, at the rate at which these chemicals are introduced into the environment constantly it is impossible. The sources of the pollution come from radioactive waste reactors, factories, fall-out from nuclear explosions and even domestic waste from cities. These cities receiving their drinking water from rivers had a higher death rate from cancer than did those whose water came from sources such as wells. At water treatment plants, the potential reactive potential of chemicals in water was such that plants were not able to remove some chemicals from teh drinking water. They feared that the relation of the removed chemicals in catch basins with each other would form into toxic compounds that would too increase cancer hazards from pollutants.

Carson also goes on to discuss the design sof insect control programs in the 60's. Wide-area "eradication" programs aimed at control or localization of imported pests are almost always unsuccessful, and extract severe penalties from non-target organisms. She explains that in designing insect control programs, the possibility of successfully controlling an insect population is more effective in natures potential than man's. Also, the species desired to be controlled reproduce once the potential of the environment to control it has weakened. Carson's underlying idea is that biological methods are the solutions to such a problem. Such a method could be the male sterilization, which consists of the release of large numbers of sterilized insects.

When released, the sterilized males would compete with the wild males to such an extent that only infertile eggs would be reproduced and the population would die out. Carson discussion of the effects of pesticides on living organisms and the non-living environment came, in Al Gore's words, as a cry in the wilderness. It was an awakening to many that began the environmental movement. In her final statement, she declares that mans desire to control nature is philosophy born in the Stone Age among the Neanderthals that has been passed on till now.

The irony is this desire for total control could become an alarming reality, but unfortunately it would not be man's true intentions; for all the research and formulated chemicals engineered to control a percentage of a species could be the extinction of many others.