AIIMS 2003 Botany Nesting Habits Assertion Reason Question

To address the question regarding the assertion and reason about the nesting behavior of birds, let's break down both parts and analyze them in detail.

Explanation of the Assertion and Reason

Assertion: "All birds, except the ones like koel (cuckoo) build nests for retiring and taking rest during nighttime (daytime for nocturnal)."

This assertion is largely true. Most birds do indeed build nests, which serve multiple purposes, including providing a safe space for resting and rearing their young. However, the assertion specifically mentions "koel (cuckoo)" birds, which are known for their distinctive reproductive strategy known as brood parasitism. Koels do not build their own nests; instead, they lay their eggs in the nests of other birds, such as the tailor bird. Thus, the assertion is true because it correctly identifies that koels do not build nests, aligning with the broader behavior of most birds.

Reason: "Koel lays its eggs in the nests of tailor birds."

This reason is also true. The koel is a brood parasite and lays its eggs in the nests of other birds, particularly the tailor bird. This behavior is a well-documented aspect of koel reproductive strategy and serves to save energy and resources that would otherwise be spent on nest building and raising young.

Correct Answer: C

Now, let's analyze why the correct answer is (C): "Assertion is true but Reason is false."

1. Assertion is True: As discussed, the assertion about most birds building nests and the koel's exception is accurate.

2. Reason is True: The reason provided is indeed accurate. It describes the behavior of the koel correctly.

However, the reasoning does not explain the assertion adequately. The assertion is about the nesting behavior of birds in general, while the reason only describes the koel's reproductive behavior. Thus, while both statements are true, the reason does not support or explain why the assertion is valid.

Clarification of Other Options

• Option A: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.
  This is incorrect because, although both statements are true, the reason does not appropriately explain the assertion.

• Option B: Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
  This option is partially correct since both statements are true, but the emphasis on the reason not being the correct explanation is insufficient without specifying that the reason pertains only to the koel.

• Option D: Both Assertion and Reason are false.
  This is incorrect as both the assertion and reason are true.

Conclusion

In summary, the correct answer is (C) because the assertion about birds and their nesting habits is true, and while the reason regarding the koel is also true, it fails to explain the assertion. The key takeaway is to differentiate between the general behavior of birds and the specific behaviors of the koel when addressing such questions.