Examkin

Question

Difficulty: MediumCell Biology, Genetics, and Evolution

In evolutionary biology, comparative anatomy provides evidence of common ancestry and evolutionary adaptation through homologous and analogous organs. Which of the following pairs of anatomical structures represents homologous organs resulting from divergent evolution?

  1. A
    Wings of butterflies and wings of birds
  2. Forelimbs of cheetahs and wings of batsAnswer
  3. C
    Eyes of octopuses and eyes of mammals
  4. D
    Fins of sharks and flippers of dolphins

Answer

Forelimbs of cheetahs and wings of bats
The forelimbs of cheetahs and the wings of bats are homologous organs because they share a common basic anatomical framework—the vertebrate pentadactyl limb—inherited from a common ancestor. Divergent evolution led these structures to adapt to distinct functional demands, such as rapid terrestrial running in cheetahs and powered flight in bats.

Step-by-Step Solution

1
Define homologous structures and divergent evolution in the context of comparative anatomy
Homologous organs are structures in different organisms that share a common embryonic origin and basic anatomical architecture derived from a common ancestor, but have evolved different functions (divergent evolution).
Establishing the defining criteria differentiates homology from analogy.
2
Evaluate the anatomical composition and lineage of the forelimbs of cheetahs and the wings of bats
Both cheetah forelimbs (adapted for running) and bat wings (adapted for flying) possess the fundamental vertebrate pentadactyl plan consisting of the humerus, radius, ulna, carpals, metacarpals, and phalanges.
Shared structural plan despite divergent functional adaptation confirms homology.
3
Contrast with analogous structures formed by convergent evolution
Pairs such as butterfly wings/bird wings, octopus eyes/mammal eyes, and shark fins/dolphin flippers do not share a common structural origin and represent convergent adaptations (analogy).
Eliminates distractors that represent convergent evolutionary adaptations.

Key Concept

Homologous Organs and Divergent Evolution
Estimated Time:1m 0s
Rate this question

Topics

Cell Biology, Genetics, and Evolution

More questions from this topic