Before You Begin
Question #46454
The Question
In a randomly mating, large population of moths, wing color is controlled by a single gene with two alleles (B and b). The population is initially in Hardy-Weinberg equilibrium. An invasive bird species enters the habitat, establishing a specific biotic interaction where it selectively preys on the homozygous recessive (light-winged) moths before they can reproduce. Which of the following is the most accurate deduction regarding the population's genetic dynamics?
Options
- A.
This (+/-) interaction induces genetic drift, causing a sudden bottleneck that randomly alters the values of p and q.
- B.
The predator acts as an agent of natural selection, causing a continuous decrease in the value of q, proving that differential reproductive success invalidates the Hardy-Weinberg null hypothesis.
- C.
The frequency of the recessive allele (q) will drop to zero in the very next generation because all q² individuals are eliminated.
- D.
This (-/-) interaction will cause disruptive selection, simultaneously increasing the values of both p² and q² while eliminating 2pq.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Hardy-Weinberg Equilibrium Variables|Biotic Interactions - Positive/Negative sign matrix
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the agents of evolutionary change (Genetic Drift vs.
Natural Selection) and fail to recognize that biotic interactions (like predation or parasitism) are the actual ecological mechanisms driving Natural Selection.
Furthermore, a common misconception is that lethal selection against a recessive phenotype instantly eliminates the allele, ignoring the 'heterozygote shielding' effect inherent in the 2pq variable.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Evolution - Class 12 |
| Concept | Hardy-Weinberg Equilibrium Variables |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |