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Question #46094
The Question
A continuous tropical rainforest, known for its high biodiversity due to latitudinal gradients, undergoes severe anthropogenic habitat fragmentation. When ecologists plot the species-area relationship (log S = log C + Z log A) specifically for these newly isolated, smaller forest patches, which of the following phenomena is most likely observed regarding the Z-value and extinction dynamics?
Options
- A.
The slope of the regression line (Z-value) steepens significantly, causing observed extinction rates to exceed those predicted by standard continuous-area models.
- B.
The Z-value remains strictly between 0.1 and 0.2 because the individual fragments represent smaller geographical areas, keeping extinction rates predictable.
- C.
The Z-value decreases as the strong latitudinal gradient of the tropics compensates for the loss of area, buffering against species extinction.
- D.
The Z-value shifts to exactly 1.15 for all taxonomic groups, stabilizing the biodiversity in the fragments due to the edge effect.
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
CBD|Nile Perch|Water Hyacinth|Invasive Species
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often rote-memorize the NCERT fact that 'small areas have a Z-value of 0.1-0.2' and 'large continents have 0.6-1.2'.
The trap (Option B) relies on this memorization.
The synthesis requires understanding that anthropogenic fragmentation violates the 'continuous habitat' assumption.
Fragmented patches act like isolated islands, causing a rapid collapse in species richness, which steepens the slope (Z-value) and leads to higher-than-predicted extinction rates.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biodiversity and Conservation - Class 12 |
| Concept | Convention on Biological Diversity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |