Babblers, a bird species, live in large cooperative groups. Each member attempts to defend the group by sounding a lo...

Amir on November 18, 2017

Please explain

why B is correct answer and not A?

3 Replies

Mehran on November 22, 2017

Let's take a closer look. This is a Paradox question.

What is the discrepancy we are trying to explain here?

The loud barklike call of the babblers that also incites other babblers to bark but alerts predators that would not notice the presence of the babblers but for these shrill barks.

The problem with (A) is that it does not resolve this discrepancy. Even if they fly faster than the predators, why would they be barking and alerting the predators to their presence.

Compare that with (B), which does serve as a possible explanation for this discrepancy.

If babblers' predators are intimidated by large numbers of babblers, this would explain why they start barking, inciting other babblers to bark, even though the predators would generally not be aware of the presence of babblers but for these barks.

Hope that helps! Please let us know if you have any other questions.

Jeremy on May 8, 2019

That still seems like a flimsy explanation for why the babblers would exhibit this strange behavior, made even further so by the use of "generally." How is it that B is the correct answer rather than E? E at least introduces a tactical element to the barking and is far less equivocal than B's "generally."

Victoria on May 8, 2019

Hi @JeremyG,

E is incorrect in this case because it is irrelevant. It provides no explanation for why the babblers would choose to bark even though it reveals their approximate location to predators, thereby failing to resolve the presented discrepancy. The question is specifically examining why the babblers would engage in this behaviour; this has nothing to do with other prey species or their proximity to the babblers.

This is why B is the stronger answer, despite the use of the word 'generally.' If babblers' predators are generally intimidated by large numbers of babblers, then it makes sense that babblers would evolve to utilize this approach due to its relative success in deterring predators.

Overall, the question is asking which one of the following, if true, would most help to explain the babblers' behaviour. B pertains directly to the babblers and their potential motivations, whereas E discusses the rate of predation on other species living in close proximity to the babblers. Therefore, B is the stronger answer.

Hope this was helpful! Please let us know if you have any further questions.