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Question #46061
The Question
The introduction of the predatory Nile Perch into Lake Victoria led to the extinction of an ecologically unique assemblage of over 200 species of native cichlid fish. When analyzing this ecological catastrophe through the lens of Paul Ehrlich’s Rivet Popper hypothesis, which of the following statements most accurately describes the fundamental impact on the lake's ecosystem dynamics?
Options
- A.
A catastrophic loss of functional redundancy due to the popping of critical 'rivets', shifting the ecosystem from a high-diversity stable state to a low-diversity unstable state.
- B.
The competitive exclusion of endemic species, illustrating that the Nile Perch acted as a superior competitor for the same limiting resources, thereby stabilizing the food web.
- C.
The removal of redundant 'rivets' from the ecosystem's 'seats', which drastically decreased species richness but maintained the overall resilience and stability of the lake.
- D.
An example of co-extinction, where the introduction of the alien species directly caused the obligate collapse of host-parasite networks, increasing functional redundancy.
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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
Co-extinction Logic|Trophic Efficiency Limits|Standing Crop quantification
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the four causes of biodiversity loss (The Evil Quartet) in isolation.
The trap lies in failing to synthesize 'Alien Species Invasion' (Nile Perch) with 'Ecosystem Stability' (Rivet Popper Hypothesis).
Furthermore, Distractor B exploits a common misconception where students confuse the mechanism of extinction in this specific NCERT example (predation by an alien species) with Gause's Competitive Exclusion Principle.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biodiversity and Conservation - Class 12 |
| Concept | Evil Quartet Drivers |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |