Argument207[快刀杀鸡]7/31作业 by ajohnares

ajohnaresUID: 2661147

题目：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.

The arguer concludes that the increase in the amount of ultraviolet radiation has caused population in the salamander species. In addition, the arguer reasons that other species, as it has occurred to salamander, will suffer from declines also. I find this argument logically unconvincing for several reasons.

First, the arguer unfairly assumes that it is the ultraviolet radiation, other than any other factor, that causes the decline in the salamander species. It is entirely possible that other deteriorating factors have made such impacts on salamander. The manifest decline is probably due to the global warming, environmental pollution, or other human activities such as deforestation and so forth. In addition, it is also possible that the decline is a normal phenomenon happening in nature, that is, numbers of species fluctuate within a certain range. Without ruling out these and other possible explanations, the arguer cannot convince me that the ultraviolet radiation results in the decline of salamander.

Second, even assuming that ultraviolet radiation contributes to the decline of salamander, the arguer provide insufficient evidence that such decline is by means of damaging the salamander eggs and preventing them from hatching. It is largely possible that the ultraviolet radiation endangers the salamander in other ways. Perhaps the undue amount of ultraviolet radiation kills the mature salamander directly. Or perhaps the ultraviolet radiation throws threat on other species, which are the prey of salamander. Without sufficient food supply, the salamander is consequently confronted with a decline in number. If so, then the conclusion made by the arguer would be further undermined.

Third, the arguer assumes unjustifiably that the population of other species is doomed to abate in future. However, this is not necessarily the case. It is known that ultraviolet radiation is damaging to delicate tissues. Nevertheless, we are not informed whether other species will abide this destructive force. It is mostly possible that salamander is one type of inferior animals and other highly-evolved species will survive when encountering the ultraviolet radiation. Lacking evidence as to the viability of other species, the arguer cannot make a hasty conclusion that the number of other species will also decline.

To sum up, the argument relies on a series of doubtful assumptions that render it unpersuasive as it stands. To bolster the argument, the arguer would have to provide clear evidence, probably via relevant scientific research, that ultraviolet radiation actually does damage to the salamander eggs and serves as the chief reason for the decline. To better assess the argument, we also need to know the circumstances of other species, for example, the endurance of ultraviolet radiation.