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Question #46616
The Question
In a specific habitat, a K-selected mammalian population undergoes a demographic transition, resulting in an age pyramid where the base is significantly narrower than the middle and top. Based on life history trade-offs and population ecology, which of the following is the most likely consequence for the reproductive cohort?
Options
- A.
Decreased intraspecific competition due to a smaller pre-reproductive cohort, leading to increased energy allocation towards fecundity.
- B.
Increased metabolic demand per unit area by the large post-reproductive cohort, forcing increased foraging effort that reduces the Darwinian fitness of reproductive individuals.
- C.
A rapid evolutionary shift towards an r-selected life history to restore the pre-reproductive base and expand the carrying capacity (K).
- D.
Enhanced resource partitioning between age cohorts, which minimizes foraging time and maximizes the intrinsic rate of natural increase (r).
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
Thermal Tolerance Ranges|Rivet Popper Hypothesis|Co-extinction Logic
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often assume that a declining population (fewer young) automatically means less overall competition.
The trap lies in failing to account for the metabolic load and resource consumption of the large post-reproductive cohort in an urn-shaped pyramid, which drives life-history trade-offs (shifting energy allocation away from reproduction towards survival and foraging).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Organisms and Populations - Class 12 |
| Concept | Thermal Tolerance Ranges |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |