Definitely, a victory 小组第5次作业 Argument 207 By9号wdx19861106

wdx19861106UID: 2821198

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: 317

The article concludes that the increase in the amount of ultraviolet radiation will cause population decline in all species. To justify this conclusion the author notes that the ultraviolet radiation could reduce the salamander population. It seems logical in the first glance, however, after particular reasoning, I find some flaws of logic in the article.

In the first place, the author doesn't tell us clearly whether the ultraviolet radiation is the only element that affects the salamander population, or there are other elements. It is entirely possible that the salamander hatch eggs in their cave, and if so, the ultraviolet radiation will harmless for salamander population. Maybe other factors, such as the air pollution and the over hunting, that reduce the salamander population. And it is possible that the population of salamander is not reduced, while the researchers don't find them all and then get the false conclusion.

In the second place, even if the relationship between ultraviolet radiation and the declining salamander population is true. We all know that different animal have various life styles, and their living circumstance is different. For instance, the shark live in the sea, and main reason why their population decline is that some people in some country live to eat the shark fin and thus catch many shark and kill them. Moreover, the chicken are living in the land and in some extent, their population will declined by the ultraviolet radiation, indeed, the number is still high and may be higher than before, and no data indicate that their population will deduce in future.


In sum, the argument is logically flawed and therefore unconvincing as it stands. To bolster it the author must provide better evidence that the decline of the salamander population is caused by the increasing ultraviolet radiation, and does more researches to test whether the other animal population reduced or increased and the reason for these events.