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Question #135659

Difficulty: 8/10 | 🟢 Free

The Question

Ecologists studying a contiguous tropical rainforest observed a historical Z-value of 0.15. Following severe anthropogenic fragmentation over a decade, the landscape was reduced to isolated patches. Regarding the species-area relationship ( $\log S = \log C + Z \log A$ ) in this altered landscape, which of the following statements is NOT correct?

Options

A.
The Z-value will shift towards a steeper slope (e.g., 0.6 to 1.2), reflecting a rapid, non-linear collapse in species richness.
B.
The steepening of the regression line indicates that species loss is directly and linearly proportional to the loss of habitat area.
C.
Niche-restricted and specialized species will transition to 'Critically Endangered' status at a faster rate than generalist species.
D.
The Z-value acts as a scale-dependent variable, demonstrating that habitat fragmentation exponentially increases extinction risk.

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

Species-Area Relationship|Z-value in Large Areas|IUCN Red List Data

Why This Question Is Tricky

Examiner Levers

Boundary Condition

Tests behavior at limits like 0, 1, infinity, or empty sets.

Difficulty Boost : +4

Common Mistakes

Conceptual Pivot: Students often confuse the logarithmic relationship of the species-area curve with a linear one.

While the equation $\log S = \log C + Z \log A$ produces a straight line on a log-log plot, the actual biological relationship ( $S = CA^Z$ ) is a rectangular hyperbola.

Therefore, species loss due to area reduction is exponential, not linear.

Furthermore, students rigidly memorize Z-values (0.1-0.2 for small areas, 0.6-1.2 for continents) without understanding that Z represents the rate of change, which steepens drastically during habitat fragmentation.

Quick Facts About This Question

Question Information

Subject	Biology
Chapter	Biodiversity and Conservation - Class 12
Concept	IUCN Red List Data
Difficulty	8
Cognitive Load	5
Target Solve Time	120 sec
Access	Free