PrepTest 131, Section 3, Question 20
The peppered moth avoids predators by blending into(56 more words not shown)
Which one of the following(11 more words not shown)
- AThe argument overlooks(13 more words not shown)
- BThe argument takes(18 more words not shown)
- CThe argument presumes,(23 more words not shown)
- DThe argument overlooks(22 more words not shown)
- EThe argument presumes,(18 more words not shown)
Reading the argument
Blending into tree bark sounds like a useful defense. If the lightest moths stood out the most, I can see why predators were most likely to notice and eat them.
But why would the darkest moths blend in best? Perhaps they were too dark. Imagine a medium-green background, with pale-green, dark-green, and medium-green moths. The pale ones could contrast the most while the dark ones still stand out. The medium-green ones could match the background best.
What we’re looking for
This could be a Goldilocks situation: the best match lies somewhere in the middle. Knowing which extreme does worst doesn't establish that the other extreme does best. For the flaw question, I'd look for the overlooked possibility that moths of an intermediate color were better camouflaged than the darkest ones.
Working the answers
- A
More predators of the light moths could give another reason for their high risk. It doesn't explain why the darkest moths must have the lowest risk among all the colors. Even if light moths had more predators, intermediate moths could still blend in better than dark ones.
- B
The moths need not control their coloring for it to affect whether predators see them. The argument's claim concerns how their appearance relates to risk. It doesn't depend on their choosing how well to blend into the background.
- C
A claim about which color group is most or least vulnerable does not require every individual of that color to face identical risk. A larger moth might be easier to spot than a smaller one of the same color, for example. The argument need not assume away such individual differences.
- DCorrect
An intermediate shade could match the background better than the darkest shade. That would leave the lightest moths as the most conspicuous without making the darkest the least conspicuous. D preserves the evidence and shows why the conclusion about the other extreme need not follow.
- E
Camouflage can matter without being the moths' only defense. They might also escape by flying away. The argument does not need to deny other defenses to compare colors; its problem is assuming that the darkest color offers the best camouflage just because the lightest offers the worst.
More Flaw questions
Learn the LSAT our way
Our platform drills Flaw questions at your level and adjusts as you improve.