QUESTION TEXT: Seemingly inconsequential changes in sea temperature due…
QUESTION TYPE: Role in Argument
CONCLUSION: Seemingly inconsequential changes in sea temperature due to global warming eventually result in declines in fish and seabird populations.
REASONING: A rise of two degrees prevents vertical mixing of water. This starves phytoplankton. That starves zooplankton. The loss of zooplankton starves the rest of the food chain.
ANALYSIS: This is a good argument. The statement about zooplankton is evidence that zooplankton will die. It ultimately supports the idea that the rest of the food chain will die if temperatures increase.
___________
- It isn’t a hypothesis. It is a fact.
- More than this. Phytoplankton are a crucial link in the food chain. If phytoplankton die then zooplankton die. Then everything else dies.
- CORRECT. Zooplankton are one of the links between warm waters and dead birds.
- The argument didn’t actually say we should stop global warming. It just described what would happen if we didn’t stop it.
- The argument only claimed that global warming would hurt fish and seabirds. It didn’t talk about land ecosystems.
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I guess that I don’t understand why this question particularly allows you to jump straight to the main conclusion. When I read the question I was looking specifically for what “zooplankton feeding on phytoplankton” had to do with anything. I know where the argument goes logically, but I felt that zooplankton argument went more to support the change in vertical mixing statement than the overall global warming argument. When the question asks what role, I would say “it supports the vertical mixing argument which in turn supports the global warming argument.” How do I not get caught in this trap in the future?
In this case, look at the structural words. For example:
Since BLORPS BLOOZLE, the declines are inevitable.
You don’t need to know what “blorps bloozle” means, or what role it plays in the sentence. The word “since” indicates that it is evidence. And the end of the sentence is a conclusory statement: a prediction. Predictions, being less certain, tend to be predictions.
E.g. “Since campuses are shut due to coronavirus, schools will be online only in the fall”.
Since = structural word
Campuses are shut = an indisputable true fact about the world
Schools will be shut in the fall = a predictive conclusion. It could obviously be wrong: something may change, and campuses may open in the fall.
Conclusions are the least certain part of the argument. The fact that the author argues the decline is “inevitable” is precisely what tells us that it is the conclusion and actually not necessarily inevitable. That depends on the strength of the author’s proofs :)