Logical Reasoning

PT149 · S4 · Q8 A study of guppy fish shows

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A study of guppy fish shows that a male guppy will alter its courting patterns in response to feedback from a female guppy.

Conclusion

A male guppy will alter its courting patterns in response to feedback from a female guppy.

Evidence

Males with more orange on one side than the other were free to vary which side they showed to a female.

Females were drawn to those males with more orange showing, and males tended to show the females their more orange side when courting.

Evaluate

Since the author is interpreting the results of a study and drawing a causal conclusion (X happens in response to Y), we can use our Explain Curious Fact mindset.

Curious Fact ... why were the males tending to show the females their more orange side when courting?

Author's Explanation ... The male guppy was swimming normally, then noticed that females were drawn to males with more orange showing, and so they altered their courting patterns to highlight more of their orange side.

Goal

Since this is Strengthen, we have two different options for how the correct answer will work:

- rule out an Alternate Explanation of the curious fact (get rid of some other explanation for why males tend to show more of their orange side).

- boost the Plausibility of the Author's Explanation (provide more evidence that corroborates the idea that males show more orange in response to feedback from a female. there are lots of ways to do this, but the #1 formula is No Cause, No Effect, i.e. an answer that shows when a male guppy does not get feedback from a female guppy, it does not alter its courting patterns to show more orange).

Which one of the following, if true, provides the most support for the argument?

Correct
When a model of a
Why this is right
This strengthens in the classic No Cause, No Effect style. The author is arguing that a male guppy shows more orange in response to feedback from a female guppy. CAUSE EFFECT feedback from female male shows more orange We can make this seem more plausible by demonstrating that when the supposed cause is absent, the effect is absent. That's what this answer does. A model of a female guppy cannot give feedback, because it's motionless. When feedback from a female wasn't present, the "showing more orange" alteration to courting patterns no longer happened.
Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.
76% picked this
In many other species females
No Impact
The fact that this mismatches with what we heard about female guppies technically has no strengthening or weakening effect, but given that superficially it feels more like weaken than strengthen, we can safely get rid of this one. Female guppies didn't seem to care as much about symmetry as they did about maximizing the quantity of orange.
3% picked this
No studies have been done
No Impact: orange heredity
The argument doesn't really care whether splotchy orange is a trait that gets passed on via the male bloodline. It only cares about whether the males were showing off their orange side in response to female feedback.
1% picked this
Female guppies have little if
No Impact
It wouldn't change this argument one bit if females were 100% orange, 0% orange, or anything in between.
4% picked this
The male and female guppies
No Impact
Separate tanks vs. the same tank doesn't have any clear relevance. This answer isn't ruling out an alternate explanation for why the males showed more orange. And it's not adding any plausibility to the story that they showed more orange in response to female feedback. So, it's not doing anything for us.
16% picked this

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