Logical Reasoning

PT7 · S1 · Q14 Marine biologists had hypothesized that lobsters

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Marine biologists had hypothesized that lobsters kept together in lobster traps eat one another in response to hunger.

Conclusion (therefore / clearly)

The marine biologists' hypothesis is wrong. rephrase: Lobsters kept together in traps do not eat one another in response to hunger.

Evidence

Lobsters can share traps for extended periods without eating one another. For example, eight lobsters shared a trap for two months without anyone eating each other.

Evaluate

Given that these eight lobsters spent two months in a trap together and never ate each other, how could we argue that the biologists are right to think that ?

Maybe two months isn't long enough? Maybe they weren't hungry enough? Maybe there was some complicating factor about these eight lobsters that disrupted the normal "eat each other" behavior? (they were in love / they were all teaming up against some predator).

The marine biologists' claim isn't saying "they IMMEDIATELY or ALWAYS eat each other", so as long as we can make an excuse for why these fools didn't eat each other, we could argue that the biologists claim is still often true.

Goal

Look for an answer that, if negated, would allow us defend the idea that lobsters in traps eat each other in response to hunger, despite this apparent counterexample.

14.

The argument against the marine biologists’ hypothesis is based on which one of the following assumptions?

Lobsters not caught in lobster
Opposite (if anything)
Since the author's goal is to show that lobsters don't eat other in traps, it would seemingly hurt her argument if they have been observed eating each other elsewhere. If we negated this and said, "Lobsters outside of traps are never observed eating each other", that would strengthen her case, not weaken.
5% picked this
Two months is the longest
Too Strong
The author doesn't need two months to be the longest period ever! She only needs to believe that two months is long enough of a time period for them to start eating each other, if they were going to ever eat each other.
12% picked this
It is unusual to find
Irrelevant Quality: unusual
Who cares whether 8 lobsters is common or rare? There's no significance to the number eight. The author is just saying, "Check it out -- a bunch of lobsters in a trap for two months and none of them ate each other."
2% picked this
Members of other marine species
Out of Scope: other species
This argument is about lobsters and makes no assumptions about any other species.
2% picked this
Correct
Any food that the eight
Why this is right
This answer has the lovable Defender "not", so we negate it and see if it weakens. "The food they lobsters obtained WAS enough to ward off hunger". Yup, that definitely weakens. If they were finding enough food to avoid being hungry, then there's no reason we'd expect them to start eating each other. And thus, this doesn't any longer look like a counterexample to the claim that "lobsters in a trap eat each other in response to hunger". A counterexample would involve hungry lobsters in a trap that didn't eat each other. And the lobsters in this trap weren't hungry, so they don't qualify as a counterexample.
Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.
79% picked this

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