Before You Begin
Question #46020
The Question
A stable, mesic climax community is subjected to a severe invasion by an alien weed species such as Parthenium hysterophorus. Based on the principles of ecological succession and population interactions, which of the following statements is INCORRECT regarding the impact of this invasion?
Options
- A.
It forces the ecosystem to revert from a stable climax state to a simplified, unstable community by outcompeting indigenous species.
- B.
The invasive species, often exhibiting r-selected traits, drives the competitive exclusion of native K-selected species due to the absence of natural predators.
- C.
It occupies vacant fundamental niches within the ecosystem, leading to an increase in species evenness and reinforcing the climax community's homeostatic equilibrium.
- D.
The invasion acts as a biological disturbance that alters realized niche availability, effectively resetting the successional clock and initiating secondary succession.
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
Climax_Community|Alien_Species_Invasion|Niche_Displacement
Why This Question Is Tricky
Common Mistakes
The Conceptual Pivot lies in understanding the components of biodiversity (specifically 'Species Evenness') and niche dynamics.
A common misconception is that climax communities have 'vacant' niches waiting to be filled, or that adding a new highly productive plant increases overall ecosystem stability.
The trap tests the realization that invasive species create monocultures, thereby destroying species evenness, usurping realized niches, and regressing the successional climax.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Ecological Succession Climax |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |