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Question #46254
The Question
The papilionaceous corolla, exhibiting vexillary aestivation, is a hallmark of the family Fabaceae. When observing various species of this family that have undergone adaptive radiation into diverse ecological niches (e.g., xerophytic shrubs vs. mesophytic climbers), the floral structure remains remarkably conserved. Which of the following statements regarding this evolutionary and morphological phenomenon is INCORRECT?
Options
- A.
The vexillary aestivation represents a homologous trait, indicating that these diverse species share a common evolutionary ancestor.
- B.
The conservation of this complex zygomorphic flower amidst vegetative divergence is primarily driven by specialized co-evolutionary pressures from specific insect pollinators.
- C.
The standard (vexillum), wings (alae), and keel (carina) represent analogous structures that have convergently evolved in these species to ensure successful cross-pollination.
- D.
The transition from actinomorphic to this highly specialized zygomorphic symmetry represents a derived evolutionary advancement rather than a primitive trait.
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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
Vexillary_Aestivation|Leguminosae|Evolutionary_Divergence
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the functional adaptation of a trait with its evolutionary origin.
Because the papilionaceous flower is highly specialized for specific pollinators, a student might mistakenly associate 'specialized adaptation' with 'convergent evolution/analogous structures'.
The trap relies on forgetting that within a single taxonomic family (Fabaceae), shared complex traits are inherently homologous and indicate divergent evolution from a common ancestor, regardless of how specialized they are.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Morphology of Flowering Plants - Class 11 |
| Concept | Aestivation Patterns |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |