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Question #132876
The Question
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): The Abingdon tortoise in the Galapagos Islands became extinct within a decade after goats were introduced on the island. Reason (R): The introduced goats possessed greater browsing efficiency, creating severe niche overlap that drastically reduced the intrinsic rate of natural increase (r) of the tortoises, culminating in competitive exclusion.
In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- A.
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
- B.
Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
- C.
Assertion is correct but Reason is incorrect.
- D.
Both Assertion and Reason are incorrect.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Ecological Fitness (Darwinian Fitness)|Alien Species Invasion Impacts|Resource Partitioning
Why This Question Is Tricky
Examiner Levers
Logical Assertion
Tests the causal relationship between two true statements.
Difficulty Boost : +4Common Mistakes
Conceptual Pivot: The question bridges a factual NCERT example (Abingdon tortoise) with the mathematical and theoretical underpinnings of population ecology (Darwinian fitness 'r' and Gause's principle).
Common Misconception: Students often memorize the tortoise-goat example merely as 'Alien Species Invasion' or 'Amensalism' without recognizing it as a classic demonstration of resource competition driving the intrinsic rate of natural increase (r) to negative values, resulting in competitive exclusion.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Organisms and Populations - Class 12 |
| Concept | Ecological Fitness (Darwinian Fitness) |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |