Logical Reasoning

PT143 · S1 · Q9 Red admiral butterflies fly

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Red admiral butterflies fly in a highly irregular fashion, constantly varying their speed, wing strokes, and flight path.

Curious Fact

Why do red admiral butterflies fly in a highly irregular fashion, constantly varying speed and flight path in a way that is clearly not energy efficient?

Author's Hypothesis

It's because the red admiral, unlike other butterflies, is not poisonous, and so it uses this funky flying style to elude predators.

Evaluate

The two pressure points of any Explain Curious Fact conversation are ....

1. Could there be some Alternate Explanation for the curious fact? 2. How plausible is the Author's Explanation?

Goal

Since this is Strengthen, we would either rule out an alternate explanation for the red admirals weird flying style (f.e. No Cause, No Effectwhen X is present, Y is present .... and when X goes away, Y goes away".

So we might see an answer like, "The red admiral doesn't start its funky flying until a predator is nearby" or "once the predator leaves, the red admiral stops doing its funky flying."

Which one of the following, if true, most strengthens the support for the scientists' hypothesis?

Correct
No species of poisonous butterfly
Why this is right
This adds some plausibility to the author's hypothesis. She thinks that red admirals have their funky flight pattern as a self-defense mechanism against predators, since they don't have a defense mechanism like being poisonous (as other butterflies do). This answer is saying, "Yeah, the butterflies who rely on being poisonous as their self-defense mechanism don't have this funky flying pattern". This is a variation of the "No Cause, No Effect" strengthener. The author thinks that "needing a way to avoid predators" causes the red admiral to have this funky flying behavior. Poisonous butterflies are avoided by predators. They don't need a way to avoid predators, so they don't have this funky flying behavior.
Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.
84% picked this
Attacks from predators are not
No Impact
This is a somewhat obvious statement for most animals in the natural world. Predators be killin', alright. However, the fact that butterflies are threatened by predators is not something we really felt we needed to establish or intensify. This fact doesn't lend any specific plausibility to the hypothesis that the funky flight pattern is a self-defense mechanism. If we were told that "predators have a really hard time killing red admirals when they fly in this irregular fashion, whereas they don't have a hard time killing red admirals when they fly normally", that would connect predators to funky flight pattern in a way that would add plausibility.
2% picked this
Many other types of butterfly
Unclear Impact
The fact that lots of butterflies have this funky flight pattern doesn't do anything to solve the causal mystery of why they have it. Is it for avoiding predators? Finding food? Finding a mate? We have no idea.
5% picked this
It is much more energy
No Impact
Comparing butterflies to heavier insects is totally irrelevant. We're just trying to solve the causal mystery behind why red admirals have this irregular flight pattern, and talking about heavier insects who are less likely to fly in an irregular fashion does nothing to help us solve the mystery.
2% picked this
All of the predators that
No Impact
We know predators avoid poisonous butterflies. It makes sense that they don't need to avoid nonpoisonous butterflies. This answer doesn't seem to tell us anything we wouldn't have already assumed (that predators are happy to go after nonpoisonous butterflies). Nothing in this answer rules out an alternate explanation for the irregular flight pattern of the red admirals, nor does it add plausibility to the idea that the weird flight pattern is connected to avoiding predators, as opposed to sneaking up on prey or seducing a mate.
7% picked this

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