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Question #46072
The Question
Paul Ehrlich’s Rivet Popper Hypothesis compares ecosystem stability to an airplane held together by thousands of rivets (species). If this hypothesis is applied to a lithosere undergoing primary succession, which of the following correctly identifies the 'key rivet on the wing' and the ecological consequence of its removal?
Options
- A.
The climax mesophytic forest; its removal permanently halts secondary succession and irreversibly depletes the soil seed bank.
- B.
The pioneer crustose lichens; their removal destroys the facilitation pathway for pedogenesis, causing an immediate collapse of seral progression.
- C.
The intermediate perennial grasses; their removal acts as a catalyst, directly facilitating the invasion of climax angiosperms by reducing competition.
- D.
The keystone top predator; its removal leads to competitive exclusion among pioneer species, thereby accelerating the rate of primary succession.
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
Climax Community|Specialist Parasites|Niche Breadth
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often associate 'keystone species' or 'key rivets' exclusively with top predators or climax species.
In the temporal dimension of primary succession, pioneer species are the ultimate 'key rivets' because their facilitation (soil building) is the absolute prerequisite for all subsequent biodiversity.
The trap relies on the misconception that climax species are always the most structurally important components of an ecosystem.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biodiversity and Conservation - Class 12 |
| Concept | Co-extinction Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |