PrepTest 131, Section 1, Question 15
The typological theory of species classification, which has(70 more words not shown)
The reasoning in the argument(9 more words not shown)
- Athe argument does(8 more words not shown)
- Bthe argument confuses(13 more words not shown)
- Cthe argument, in(16 more words not shown)
- Dthe argument takes(18 more words not shown)
- Ethe argument does(7 more words not shown)
Reading the argument
These theories classify organisms using different criteria. The typological theory looks at physical features. The mainstream biological theory, as described here, separates the sibling species because they cannot interbreed.
Different criteria can produce different groupings. Imagine comparing a small dog, a small fox, and a wolf. A classification focused on size might group them differently from one focused on ancestry. We cannot choose the better classification merely by announcing that the two systems disagree.
That is what worries me about the conclusion here. Why must the typological theory separate organisms that look indistinguishable? The demand comes from the competing biological theory. The author treats that theory's criterion as correct and then rejects typological classification for failing to follow it.
What we’re looking for
Calling the biological theory “mainstream” does not supply the missing justification. To criticize one theory by applying its rival's standard, we first need a reason to accept that standard. That is the assumption I would look for in the flaw answers.
Working the answers
- A
We do not have to evaluate every aspect of a theory to find a genuine reason to reject it. Similarly, one serious disqualifying act might justify rejecting a political candidate without reviewing every policy the candidate supports. The problem here is whether the stated objection actually establishes a defect, not whether the discussion covers every possible aspect.
- B
The author does not move from a requirement for species distinction to a claim that meeting that requirement guarantees distinction, or make the corresponding mistaken move in the other direction. The dispute is over which criterion should determine the classification in the first place.
- CCorrect
The author assumes that the biological theory's separation of sibling species is correct, then faults the typological theory for not reaching the same classification. But disagreement with another theory is not by itself a refutation. The argument needs support for treating the rival's standard as the proper one.
- D
A single genuine counterexample can be enough to refute a theory; we do not always need several. But we also need the example actually to conflict with what the theory says. The inability of these organisms to interbreed does not contradict a classification based on appearance. It becomes a supposed defect only when we assume the biological theory's criterion is the right one. That assumed standard, not the number of examples, is the issue.
- E
The passage gives us the fact that the sibling species cannot interbreed. We do not need an explanation of the biological mechanism to understand the disagreement between the classification systems. The missing justification concerns why interbreeding should govern the classification, not why these organisms cannot do it.
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