处女作Argument207，求piapia~thanks！

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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 author first shows the discovery that the population of salamander that lays its eggs in mountain lakes has decreased, then he uses the common sense to relate the increasing ultraviolet radiation to the supposed damaging of the salamander eggs. Finally the author predicts the population declines in other species.

However, the evidences the author cites are not valid and convincible. First, the result of the discovery is not accurate and in detail. The discovery only shows that the population of salamander that lays its eggs in mountain lakes has declined. But I can raise some questions to the result: Has the total population of salamander decreased or just that of which can lay eggs? Where do the salamander lay their eggs? Do they just lay eggs in the mountain lakes? Lacking such important data and details, maybe we can assume that only the specific kind of salamander decreased in its population and the author cannot use the result to summarize the general situation.

Second, there are many factors that he or she has overlooked or chosen to ignore. Other factors may include the increasing in their natural enemies, the warmer temperature of that area, the water or air pollution that impedes their growths, the humans' destruction of their habitat. The factors above can also have the same result as the ultraviolet radiation has.

In addition, the author presumes that the eggs are delicate tissues so that he can prove ultraviolet radiation really harms the eggs. Unfortunately, there is no evidence to validate that presumption. Although the eggs have no protective shells, they can have other methods to prevent the damage of ultraviolet radiation. For instance, it is possible there is some liquid that reflect ultraviolet radiation, or maybe there is a membrane that isolates the inner part of the egg from ultraviolet radiation. Besides, the author did not clarify the effects of the ultraviolet radiation on the eggs. The author has not given strong reasons for the ultraviolet radiation preventing eggs from hatching. The reality, however, may be opposite: the ultraviolet radiation turns out to be necessary to the hatching process. Or the ultraviolet radiation does not prevent hatching but cause other problems such as abnormalities in shape and function.

Finally, even assuming that the population of salamander really declined, the author cannot pontificate that it will result in population declines in other species, because the relationship between salamander and other species is unclear. Perhaps some species that compete with salamander increase in population due to lacking a kind of competitors. And the populations of natural enemies of salamander may keep stable because they can prey on other alternatives instead of salamander.

In sum, the evidences that the author cites are inconvincible, the deduction is invalid because of the unreliable presumption. And the author fails to consider other factors and makes a hasty prediction without discreet survey and investigation. If the author want to convince me that his prediction is reasonable, he must improve the all the aspects above.