Logical Reasoning

PT144 · S4 · Q25 Many bird and reptile species use

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Many bird and reptile species use hissing as a threat device against potential predators.

Given that ...

The ancestors of modern birds and reptiles would have had predators who didn't have the ability to hear hissing sounds,

How could it be that ...

These ancestors evolved the ability to hiss?

Evaluate

This paradox is a little harder than average to find. Usually, the final claim in the paragraph is the Surprising Claim we need to explain. But here, it feels more like the final claim is a background fact, and the surprise comes earlier.

The author is convinced that early ancestors of birds and reptiles would have had the ability to hiss, even though their predators wouldn't have been able to hear hissing sounds.

Goal

To reconcile this paradox and explain why these ancestors would have evolved hissing behavior, we could go a couple different ways:

1. Yes, the predators couldn't hear the hissing, but the hissing still worked as a deterrent to predators because _______ .

2. Yes, the hissing wasn't an effective deterrent against predators because they couldn't hear it, but the hissing still had adaptive value because _______ .

25.

Which one of the following, if true, most helps to resolve the apparent discrepancy in the information above?

Like its potential predators, the
No Impact
This maybe even deepens the paradox, because now we're even more confused by the hissing behavior in these ancestors. THEY couldn't hear it. Their PREDATORS couldn't hear it. What was the point of this hissing? Why did it evolve? This answer provides no answers.
3% picked this
The common ancestor of bird
No Impact
This doesn't offer any explanation for why these ancestors possessed an ability to hiss. It's saying they probably had several ways to deter predators, but as far as we know, hissing was not one of those (since the predators couldn't hear the hissing). So we still have no explanation for these ancestors hissed.
13% picked this
Correct
The production of a hissing
Why this is right
We can use this answer to complete our first blank: 1. Yes, the predators couldn't hear the hissing, but the hissing still worked as a deterrent to predators because .... the hissing made the birds and snakes look bigger, which scares off predators.
Skill tested: Paradox · how this choice captures the argument's function is the move to repeat next time.
74% picked this
The use of hissing as
Cheating the Paradox
This answer helps explain why you'd evolve hissing as a predator deterrent: it's less energetically costly. That's a good thing. But to use this answer, we'd have to act like the hissing was a predator deterrent (a threat device). We were told that predators would have been unable to hear the hissing, so we have no reason to believe that hissing was used as a threat device.
5% picked this
Unlike most modern bird and
No Impact
In addition to the fact that any predators these ancestors did have couldn't hear the hissing, this answer is telling us that there really weren't that many predators to begin with. Cool, so these ancestors had very few predators, and those predators couldn't hear the hissing. So it sounds like the hissing had nothing to do with predators. So .... why did this ancestor evolve the ability to hiss? This answer provides no answer to that question.
4% picked this

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