TOPIC: ARGUMENT53 - Thirteen years ago, researchers studied a group of 25 infants who showed signs of mild distress when exposed to unfamiliar stimuli such as an unusual odor or a tape recording of an unknown voice. They discovered that these infants were more likely than other infants to have been conceived in early autumn, a time when their mothers' production of melatonin-a hormone known to affect some brain functions-would naturally increase in response to decreased daylight. In a follow-up study conducted earlier this year, more than half of these children-now teenagers-who had shown signs of distress identified themselves as shy. Clearly, increased levels of melatonin before birth cause shyness during infancy and this shyness continues into later life.
WORDS: 494 TIME: 上午 0:30:00(超时完成) DATE: 2006-7-30
（我自己把拼写和小错误改了，但刚开始写argu，不知道大的方面有没有什么问题，比如逻辑推理方面的，还请大家指教，我感觉遣词造句还有些生硬）
The argument is well presented, but not thoroughly well-reasoned. The author concludes based on the researchers' study thirteen years ago and earlier this year that increased levels of melatonin before birth cause shyness during infancy and this shyness continues into later life, which seems logical at the first glance, however is logically unflawed in several respects listed below after in-depth examination.
First of all, the study conducted by researchers is problematic in several respects: first, the size of the study is not so large as to draw any conclusion whatsoever and we are not informed that the group of infants is representative of all the infants. For that matter, it is as likely that the infants involved in the study have some distinctive features distinguishing them from the ones in the overall pool such as that they are not taken good care of immediately after birth. Moreover, absent evidence to support that the infants are indeed in an anomalous state when exposed to unfamiliar stimuli, it is entirely possible that it is the nature of infants to show signs of mild distress. Either of the scenarios, if true, would serve to undermine the authenticity of the study, further weaken the conclusion to a great extent.
Secondly, the author concludes based on the known correlation between the mild distress of the infants and increased levels of melatonin in their mother's body that the latter is attributable to the former. Yet, no evidence is provided to substantiate the correlation, it is entirely possible that other factors such as the feeling of hunger or discomfort other than melatonin lead directly to mild stress. Moreover, we are not informed that the increased level of melatonin in mother's body can exert direct influence on her child, thus we have good reasons to doubt whether the melatonin can have any bearing on the infants. Lacking such evidence, the author's claim cannot convince me at all.
Finally, the author infers from earlier study that the increased melatonin will take effect into infants' later life. Yet the inference is not logically convincing because the author overlooks other factors that might affect the maturing of the infants over the thirteen yeas passed. For example, some infants may experience great misfortune or emotional breakdown such as the failure of love and the loss of dignity, thus they are quite likely to show signs of shyness. Moreover, we cannot rely on the self-evaluating of shyness by teenagers themselves; there might be too much subjective factors involved.
In sum, the argument is not persuasive as it stands. To strengthen it, the author may enlarge the width of the study and collect their study objectives from a more lager pool to make the infants involved representative. Also, more evidence needs to be provided to justify that there is direct relationship between increased melatonin and the mild distress. Meanwhile, the author must rule out other alternatives that may lead to shyness of teenagers in their growing process.