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Question #46419
The Question
In the Species-Area Relationship (S = CA^z), the z-value for a large continental area is typically 0.6 to 1.2. Consider a highly degraded continental landscape that contains isolated 'Sacred Groves' acting as temporal refugia. Which of the following statements correctly explains how these groves disrupt standard SAR expectations?
Options
- A.
They exhibit a steeper slope (z > 1.2) because they represent the climax community of the entire continent compressed into a small region.
- B.
They artificially deflate the localized z-value by maintaining disproportionately high species richness (S) despite a drastically reduced area (A), delaying the expected extinction debt.
- C.
They conform strictly to a z-value of 1.15, identical to frugivorous birds in tropical forests, due to their undisturbed canopy architecture.
- D.
They decrease the y-intercept (C) of the SAR curve because their extreme isolation prevents the influx of new species over geological time.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Z-value in Large Areas|Stellar Distance vs. Geological Time|Sacred Groves as Refugia
Why This Question Is Tricky
Common Mistakes
The 'Conceptual Pivot' lies in understanding the mathematical reality of the z-value (slope).
Students often memorize that continents have high z-values (0.6-1.2) but fail to realize that a steeper slope means species richness is highly dependent on area.
By introducing 'Sacred Groves' (refugia), the question tests if the student understands that preserving high biodiversity in a small, fragmented area artificially flattens the expected slope, decoupling the standard area-species rule from geological time expectations.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Evolution - Class 12 |
| Concept | Stellar Distance vs. Geological Time |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |