Logical Reasoning

PT117 · S3 · Q15 Seemingly inconsequential changes in sea

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Seemingly inconsequential changes in sea temperature due to global warming eventually result in declines in fish and seabird populations.

Conclusion

Seemingly inconsequential changes in sea temperature due to global warming eventually result in declines in fish and seabird populations.

Evidence

Even just a seemingly inconsequential two degree increase in sea temperature prevents vertical mixing of seawater, which limits how many nutrients flow up to phytoplankton (which imperils the population of phytoplankton), which imperils the population of zooplankton which feed upon it, which imperils the rest of the food chain, which feed upon zooplankton.

Evaluate

Whenever we do Main Conclusion and Role, we prime our brain to listen for a First Sentence Conclusion or a Rebuttal Conclusion, since those are the two dominant strains for those question types.

Without that tendency-awareness on Main Conclusion and Role, our work can be much harder. If we listen to this first sentence knowing there's a high probability it's the conclusion, then it's easier to hear the rest of the paragraph as fleshing out the causal chain that gets us from a change in sea temperature to a decline in fish and seabird populations.

They don't give us any keywords to go off of, other than the Support Indicator "since" in the final sentence. "Since X, Y" always indicates that Y is a conclusion supported by X (or, in causal contexts, that Y is an effect of X).

In this paragraph, we could call "the declines are inevitable" an intermediate conclusion, but it seems more appropriate to just see that last sentence as we do the 2nd and 3rd sentences: presenting cause/effect relationships.

Words like since / because / thus / so can be used in causal ways, where we don't attach our normal Support Indicator or Conclusion Indicator thoughts to them.

for example: Kevin broke his leg because he fell off the roof. Kevin fell off the roof, thus breaking his leg.

Goal

They're asking us about the second to last claim, which was part of the Support (everything after the first sentence was part of the support).

15.

Which one of the following most accurately describes the role played in the argument by the statement that zooplankton feed upon phytoplankton?

It is a hypothesis supported
Not a Hypothesis
A hypothesis means a speculative causal explanation for something or a speculative guess about something. It is a fact that zooplankton feed upon phytoplankton. We can't call that a hypothesis.
2% picked this
It is intended to provide
Wrong Role
Even if we awkwardly stretched this to potentially be saying something true, it would still not be accurately expressing the role. The fact that zooplankton feed upon phytoplankton is an example of a feeding habit that could be impacted by a disruption to the vertical mixing of seawater. But the role of "zooplankton feed upon phytoplankton" was simply one more step in the causal chain that gets us from warmer sea temperatures to declines in fish and seabird populations.
25% picked this
Correct
It helps show how global
Why this is right
This identifies the Support role that our claim had = "it helps to show" We would want something resembling the Conclusion to follow that phrase, and the idea of "global temperature changes affecting larger sea animals indirectly" is a pretty good match for what the first sentence is talking about. So this answer just says, "the claim we're asked about helps to show how the first sentence is true", which just means "the claim we're asked about is one of the Premises for the Conclusion in the first sentence".
Skill tested: Role · how this choice captures the argument's function is the move to repeat next time.
60% picked this
It is offered as one
Bad Conclusion Match
The author never said that global warming must be curtailed. There are no prescriptions, recommendations, or any other normative language in here. The argument just identifies and then explain a cause/effect relationship.
1% picked this
It is offered in support
Bad Conclusion Match
The author never said that global warming poses a threat to all organisms. The conclusion only indicates that global warming poses a threat to fish and seabird populations.
13% picked this

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