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Question #46653
The Question
An ecotone between a tropical rainforest and a savanna exhibits a pronounced 'edge effect', supporting a highly stratified and diverse community. If anthropogenic habitat fragmentation severely restricts the spatial area of this ecotone, how will the species-area relationship (log S = log C + Z log A) most likely be affected?
Options
- A.
The Z-value will remain constant between 0.1 and 0.2, as the inherent edge effect compensates for the loss of habitat area.
- B.
The Z-value will fluctuate wildly and steepen, as the restricted area falls below the minimum viable range for edge-specialists, disrupting niche partitioning.
- C.
The Y-intercept (C) will increase significantly because the remaining species will be forced into higher stratification within the restricted zone.
- D.
The Z-value will decrease towards zero, indicating that species richness in highly stratified ecotones is independent of spatial extent.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Ecotone and Edge Effect|Rivet Popper Hypothesis|Co-extinction Logic
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the NCERT fact that the Z-value is a constant 0.1-0.2 for small areas and only steepens (0.6-1.2) for entire continents.
They fail to synthesize this with 'The Evil Quartet' (Habitat Fragmentation).
The trap lies in assuming that the 'edge effect' (which naturally boosts biodiversity) makes the ecotone resilient to area restrictions.
In reality, edge-specialists are highly sensitive to minimum viable area thresholds, and fragmentation destabilizes the expected richness-area correlation.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Organisms and Populations - Class 12 |
| Concept | Ecotone and Edge Effect |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |