QUESTION TEXT: Red admiral butterflies fly in a highly irregular…
QUESTION TYPE: Strengthen
CONCLUSION: The red admiral butterfly’s irregular flight style evolved to help the butterfly avoid enemies.
REASONING: Predators will eat nonpoisonous butterflies like the red admiral. Predators avoid poisonous butterflies.
ANALYSIS: This sounds like a good argument. But the author ignores the possibility that all butterflies have an irregular flight style, and that red admirals use some other defense to avoid predators.
I mean, have you ever looked at a butterfly? Those things fly all over the place. We need more information about butterfly flight styles.
___________
- CORRECT. Poisonous butterflies don’t need to avoid predators. If none of them have flight styles similar to the red admiral’s, then that strengthens the idea that the red admiral developed this flight style because because red admirals aren’t poisonous.
- Who cares? Being crushed by a car is not the most common cause of death for humans, but you still take precautions against getting crushed by cars, right?
It almost never matters what the most common or most important cause of something is. - It’s hard to say what effect this has. If other non-poisonous butterflies share the flight style, then that helps the argument.
But if poisonous butterflies share the flight style, then that hurts the argument.
This answer doesn’t say which other butterflies share the flight style. - Who cares about other, heavier insects. I imagine that anything a small insect like a butterfly does is more energy efficient than what a large insect does.
I mean, humans are more energy efficient in their movements than elephants, but that doesn’t tell us much about human or elephant behavior. - This provides zero information. We know nothing about how those other non-poisonous butterflies avoid predators.
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Luke says
Hey Graeme, I have a question concerning your analysis as to what’s wrong with the reasoning in the stimulus on this one. You said “This sounds like a good argument. But the author ignores the possibility that all butterflies have an irregular flight style, and that red admirals use some other defense to avoid predators.” If all butterflies fly in a particular fashion, then by definition, wouldn’t this fashion necessarily be the regular one? The author states that the highly irregular fashion is due to the constant change in speed, wing strokes, and flight path. But if all butterflies constantly changed their speed, wing strokes, and flight path, then this flight pattern would be the regular one. I understand your explanation as to why (A) is the correct answer, but the above mentioned part of the analysis threw me off, because you seem to imply that the author was comparing the fashion in which a butterfly flies to the fashion in which other winged creatures fly, which I hadn’t considered.
TutorLucas (LSAT Hacks) says
That’s a good question, but here’s why we can argue that the word “irregular” here isn’t being used to suggest that the way they fly is “irregular among butterflies.” The stimulus tells us that the red admiral constantly varies its speed, wing strokes, and flight path. Regardless of whether or not this way of flying is something that is common among butterflies, common sense dictates that is an irregular way of getting around–why put in the effort of constantly varying how you fly when it would clearly be such a hindrance to survival? And in fact, the last sentence even refers to this way of flying as “clearly energy-efficient”, suggesting that the irregularity is the constant shifts in speed, wing strokes, and flight path, and not that this way of flight is “irregular among butterflies.”