argument 207[triple week]第九次作业by 泡面

泡面UID: 2513568

TOPIC: ARGUMENT207 - It is known that in recent years, industrial pollution has caused the Earth's ozone layer to thin, allowing an increase in the amount of ultraviolet radiation that reaches the Earth's surface. At the same time, scientists have discovered, the population of a species of salamander that lays its eggs in mountain lakes has declined. Since ultraviolet radiation is known to be damaging to delicate tissues and since salamander eggs have no protective shells, it must be the case that the increase in ultraviolet radiation has damaged many salamander eggs and prevented them from hatching. This process will no doubt cause population declines in other species, just as it has in the salamander species.
WORDS: 352
TIME: 0:30:00
DATE: 2009-7-29

Grounding on the discovery that the industrial pollution made the Earth’s ozone layer beocome thin, thus lead to increased amount of ultraviolet radiation reaches the earth's surface, and the discovery of the simultaneous declined population of a species of salamander eggs in mountain lakes, the arguer come s to the conclusion that the increase in ultraviolet radiation damages salamander eggs anf prevent them form hatching and thus the destruction on other species as well. Persuasive as it seems , the author virtually features some flaws once submitted to further examination.

Merely based on the phenomenon of the decline in population of one species of salmander eggs and the simaultaneous increase in amount of the ultraviolet radiation, it is too rashly to make the conclusion that the ultraviolet radiation is the direct reason to cause the decrease of salamander eggs. First of all, the increase of the amount of ultraviolet radiation is not assured to reach every inch of the earth. It is entirely possible that in the habitats of the salamanders and the place where they lay their eggs, ultraviolet radiation is rare or the amount of ultraviolet raditaion in that place has not increased. Thus the increase of ultraviolet radiation has nothing to do with the reducttion of population of salmander eggs.
On the other hand, the author is flawed to feature that the ultraviolet radiation is the only and direct reason to give rise to declined population of salmander eggs. There are many other reasons should taken into consideration of the depletion of salamander eggs in advance. For example, the author should provide information that whether there had floods, volcano erruption or other nature catastrophe during the period of investigation, and as well as the possibility that enermy of salamander has swallowed the salamander eggs, since these factors will possibly bring about decline of the salamander eggs directly.

Moreover, the author provides no information that the ultraviolet radiation-influenced eggs will be impeded the hatching of these eggs. Since the former population of hatched eggs has not given. The author fails to substatiate that the hatched salamder are fewer than before which the salamander eggs are not influenced.

Additonally, granted that ultraviolet radiation is detrimental to the salamander eggs, the author makes an unconvincing comparation between the salamanders of this species to the other species. Common sense informs me that the other species are not identical with this species. There are differences existing so that they can be classifies into several dissimilar species. Lacking the detailed evidence that all the other species possess no preventive shells or other kind of preventive organs, the author 's statement tend to be unconvincing.

To sum up , to bolster the author’s statement, he/she should provide detailed information in several aspects.(1) The exact amount of the ultraviolet radiation that reach the habitats of the salamander eggs.(2)The possible and direct elements that cause the declined population of salamander eggs (3)the hatching numbers before the
increase of ultraviolet raditaion(4) the sturcture of salamnder eggs and a detailed information of all species. Only based on all those evidence, could the author make further conclusion.