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Question #46484
The Question
The evolutionary trajectory from Homo habilis (650-800 cc) to Homo neanderthalensis (1400 cc) demonstrates a marked increase in cranial capacity. In the context of population ecology and metabolic trade-offs, which of the following shifts was an obligatory consequence of this encephalization?
Options
- A.
A transition towards r-selected traits to compensate for the high maternal mortality associated with larger fetal head sizes.
- B.
A reduction in the intrinsic rate of natural increase (r) coupled with intensified K-selected traits, prioritizing parental investment over raw reproductive output.
- C.
A linear increase in Darwinian fitness achieved by maximizing the number of offspring produced per reproductive cycle.
- D.
A decrease in the metabolic demands of the digestive tract, allowing a simultaneous increase in both cranial capacity and the intrinsic rate of increase (r).
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
Hominid Cranial Capacity|Ecological Fitness (Darwinian Fitness)
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often conflate 'Evolutionary Advancement' (larger brains) with an absolute increase in 'Darwinian Fitness' (misinterpreted purely as high reproductive rate 'r').
The trap lies in failing to recognize that advanced hominids sacrificed raw reproductive output (r-selection) for high offspring survival probability (K-selection) due to the immense metabolic and developmental costs of encephalization.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Evolution - Class 12 |
| Concept | Hominid Cranial Capacity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |