argument45 [Jet小组] 第三次作业

yimengshanUID: 2392100

TOPIC: ARGUMENT45 - The following appearedas an editorial in a wildlife journal.
"Arctic deer live on islands in Canada's arcticregion. They search for food by moving over ice from island to island duringthe course of a year. Their habitat is limited to areas warm enough to sustainthe plants on which they feed, and cold enough, at least some of the year, forthe ice to cover the sea separating the islands, allowing the deer to travelover it. Unfortunately, according to reports from local hunters, the deerpopulations are declining. Since these reports coincide with recent globalwarming trends that have caused the sea ice to melt, we can conclude that thedecline in arctic deer populations is the result of deer being unable to followtheir age-old migration patterns across the frozen sea."
WORDS: 319         

In the editorial, the author asserts thatit is the global warming that causes the decrease of deer population, becausethe increasing temperature has melted the ice which covered the sea separatingthe islands. To support the assertion the author explains the Arctic deer'sliving condition and migration habit. Yet, the argument rests on a series ofunsubstantial assumptions, and therefore unpersuasive as it stands.

A threshold assumption upon the argument isthe reports from local hunters are effective while the author fails tosubstantiate it. Canada'sarctic region has a large area and it is impossible for the local hunters tomake conclusion just according to their local circumstance. It is entirelypossible that the over many local hunters make deer fearful of their originalliving condition, so their migrations to other islands lead to the local deerpopulation's decrease. Accordingly, perhaps the other areas’ deer populationhas experienced an increase. Therefore the author cannot draw any absoluteconclusion until the reports can represent the whole area's circumstance.

Even assuming the reports arerepresentative, the arguments rests on an additional assumption that thereexists causal relationship between global warming and the decrease of deerpopulation. There are many factors that contribute directly to the decreasingnumber. Perhaps the excess hunting make the deer’s population declining, orperhaps it is the appearance of natural enemy or the shortage of food thatcause the actuality. The author establishes the causal relationship justaccording to a coincidence; however, the author must provide more evidence toprove the coincidence is a causal relationship.

In conclusion, to convince me that theglobal warming cause the decline of deer population, the author must providemore evidence to prove that the deer population did experienced a decline inthe past years. Also, the author should establish the causal relationshipbetween global warming and deer population in a more convincing way, not justby a coincidence.