For bird species in which females are the sole incubators, a male can

Question

For bird species in which females are the sole incubators, a male can increase the female’s percentage of time spent on the nest (nest attentiveness) by feeding the incubating female on the nest (incubation feeding). Given the benefits of nest attentiveness and the potential ability of incubation feeding to increase attentiveness, the question arises of why species vary in their rate of incubation feeding. One hypothesis suggests that greater incubation feeding is required in harsher microclimates because there the cost of leaving eggs unattended is greater. Under this hypothesis, nest attentiveness and incubation feeding rates should be highest in species using nest sites that are exposed to extreme temperatures that can threaten embryo development or survival. An alternative hypothesis is that incubation feeding is constrained by nest predation; increased trips to the nest are hypothesized to attract the attention of predators. Females can consume more food in one foraging trip off the nest than a male can bring back to the nest in one trip, so the number of trips to the nest can be reduced by females obtaining most of their own food. Therefore, under the nest predation hypothesis, species with a higher risk of nest predation should show increased foraging by females and lower rates of incubation feeding by males.

1. The nest predation hypothesis implies that in situations where there is a high risk of nest predation, which of the following statements regarding the behavior of nesting birds is most likely to be true?

A. It is less threatening to embryo development to leave a nest unattended at times than it is to draw attention to the nesting site.
B. Embryos will be most successful in situations where females forage for less than half of their own food during incubation.
C. Incubation feeding is likely to increase steadily as embryos develop.
D. Attempts at incubation feeding by males will be rejected by incubating females.
E. Incubation feeding will occur only when a harsh microclimate is combined with a high risk of predation.

2. According to the nest predation hypothesis as it is described in the passage, which of the following should occur when a bird species in which females are the sole incubators is at high risk of nest predation?

A. Females will go without food in the interest of keeping the nest inconspicuous.
B. Females will leave the nest unattended periodically in order to forage for food for themselves.
C. Males will supply all of the females’ food throughout the incubation period.
D. Males will bring food to females only at times when embryo development is threatened by extreme temperatures.
E. Males will obtain most of the females’ food, but females will occasionally forage for food themselves.

3. Which of the following best describes the structure of the passage as a whole?

A. A scientific debate is noted, and then certain research methods that could help resolve that debate are discussed.
B. A scientific study is described, and then various implications of that study are summarized.
C. A scientific question is introduced, and then potential answers to that question are discussed.
D. A hypothesis is presented, discussed, and then rejected in favor of a second hypothesis.
E. Factual information about a certain situation is provided, and then contradictory interpretations of that information are noted.

Show Spoiler

Attachment:

GMAT-Club-Forum-vn40e7de.png [ 103.43 KiB | Viewed 2873 times ]

Attachment:

GMAT-Club-Forum-r8iqsr6a.png [ 66.75 KiB | Viewed 2866 times ]

Attachment:

GMAT-Club-Forum-4iwe53iv.png [ 66.42 KiB | Viewed 2871 times ]

Attachment:

GMAT-Club-Forum-8aqg91e7.png [ 57.81 KiB | Viewed 2868 times ]

Show Answer Question #1

Official Answer

A

Show Answer Question #2

Official Answer

B

Show Answer Question #3

Official Answer

C

Pro tip: Combine official questions for familiarity with GMAT Club Tests for analytics and tougher Focus-level practice so the real exam feels manageable. Explore →

Sajjad1994 · Answer

Explanation

3. Which of the following best describes the structure of the passage as a whole?

Explanation

The passage begins by   introducing a phenomenon:   in bird species where females exclusively incubate eggs, males can increase the female's nest attentiveness by feeding her while she's on the nest.  It then poses a question:  why do species vary in their rates of incubation feeding? Two hypotheses are presented to address this question.

The first hypothesis suggests that greater incubation feeding is needed in harsher microclimates because leaving eggs unattended in such conditions poses a greater risk to embryo development or survival. This hypothesis implies that nest attentiveness and incubation feeding rates should be highest in species inhabiting extreme temperature conditions.

The second hypothesis proposes that incubation feeding is constrained by nest predation. According to this hypothesis, increased trips to the nest, such as those required for incubation feeding, could attract predators. It suggests that species facing a higher risk of nest predation may exhibit increased foraging behavior by females and lower rates of incubation feeding by males.

The passage doesn't clearly favor one hypothesis over the other; instead, it presents both hypotheses as potential explanations for the observed variation in incubation feeding rates among bird species.

Therefore, the best description of the structure of the passage as a whole is  C.

(C)  accurately reflects how the passage introduces a scientific question (why do species vary in their rates of incubation feeding?) and then discusses two potential answers (hypotheses) to address that question.

Answer: C

adarshravindra · Answer

Q2, isnt E the right answer as male is bringing most of the food and only lower rates of foraging in females?

Shayan08 · Answer

"  Therefore, under the nest predation hypothesis, species with a higher risk of nest predation should show increased foraging by females and lower rates of incubation feeding by males."

This part of the passage suggests that there will be lower rates of incubation feeding and high foraging. Thats why male bringing most of the food isnt a viable option

VerbalBot · Answer

Automated notice from GMAT Club VerbalBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.

For bird species in which females are the sole incubators, a male can

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Reading Comprehension (RC) Questions

For bird species in which females are the sole incubators, a male can

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards