Question

Explain convergent evolution with an example.

Hint:

Look for similar structures in UNRELATED organisms - that similarity is analogous, not homologous.

Answer 1

Step 1: Define convergent evolution:
Convergent evolution is the process by which unrelated species, living in similar environments and facing similar selection pressures, independently evolve similar (analogous) structures or traits, without inheriting them from a common ancestor.

Step 2: Contrast with divergent evolution:
This is the opposite of divergent evolution (adaptive radiation), where related species from a common ancestor evolve different structures suited to different environments/functions.

Step 3: Give an example:
The wings of butterflies (insects) and the wings of birds are a classic example: both serve the same flight function and look superficially similar, but they evolved completely independently from very different ancestral structures - the two groups are not closely related.

Final Answer:
Convergent evolution produces superficially similar (analogous) structures in unrelated organisms facing similar environmental pressures - e.g. the wings of butterflies and birds, or the streamlined body shape of sharks (fish) and dolphins (mammals).