Which one of the following is an example of Analogy ?

Question

Accepted Answer

Option 3, "Wings of birds and bat," is the correct answer as an example of analogy. In biological terms, analogy refers to structures that serve similar functions and may appear similar due to convergent evolution, but do not share a common ancestral origin. The wings of birds and bats are analogous structures because they both serve the function of flight and have similar shapes adapted for this purpose. However, they evolved independently in these two groups of animals. Birds are avians, and their wings are modified forelimbs with feathers, while bats are mammals, and their wings are formed by a membrane stretched between elongated fingers. This independent evolution of similar features in different lineages due to similar environmental pressures is a classic example of analogy.

Now, let's explain why the other options are incorrect:

1. **Hand of man and leg of horse**: This is an example of homology, not analogy. Homologous structures are those that are derived from a common ancestor, even if they serve different functions. The hand of a human and the leg of a horse are both derived from the forelimb of a common tetrapod ancestor, making them homologous, not analogous.

2. **Testis in males and ovaries in female develop from same embryonic tissue**: This is also an example of homology. Both the testis and ovaries develop from the same embryonic tissue, known as the gonadal ridge, in vertebrates. This shared developmental origin indicates homology, not analogy.

4. **Mouth parts of honeybee and housefly**: The mouthparts of a honeybee and a housefly are examples of homology. Although they have adapted to different feeding mechanisms (bees for sucking nectar and flies for sponging liquids), they are derived from the same basic insect mouthpart structure, indicating a common evolutionary origin.

In summary, Option 3 is the correct example of analogy because it illustrates how similar functions (flight) can evolve independently in different lineages (birds and bats) due to similar environmental pressures, despite having different evolutionary origins.