Before You Begin
Question #45605
The Question
Paul Ehrlich’s Rivet Popper hypothesis compares ecosystem stability to an airplane. Suppose a keystone species in such an ecosystem possesses a gene for thermal tolerance that exhibits multiple allelism. If the ecosystem undergoes continuous 'rivet popping' (species loss and habitat degradation) leading to severe population bottlenecks, which of the following statements correctly explains the ultimate collapse of the ecosystem during a sudden climate shift?
Options
- A.
The continuous loss of species triggers adaptive radiation, but the keystone species fails to survive because multiple allelism restricts the formation of new recombinants.
- B.
The population bottleneck eliminates specific alleles from the gene pool, reducing population heterozygosity and stripping the species of the genetic variants required to tolerate new thermal extremes.
- C.
The loss of 'rivets' forces the multiple alleles to undergo convergent evolution, resulting in a high degree of homozygosity that is lethal under thermal stress.
- D.
Multiple allelism inherently reduces the ecosystem's resilience because it promotes genetic drift, which accelerates the Rivet Popper effect during environmental fluctuations.
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
Allelic_Variation|Fitness_Landscape|Functional_Redundancy
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Bridging macro-ecology (Rivet Popper Hypothesis) with micro-genetics (Multiple Allelism and Genetic Drift).
Students often memorize these concepts in isolation.
The trap lies in misunderstanding how a reduction in ecological biodiversity directly translates to a reduction in genetic diversity (loss of multiple alleles via bottleneck), thereby destroying the population's buffering capacity against environmental shifts.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Principles of Inheritance and Variation - Class 12 |
| Concept | Multiple Allelism Limitation |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |