Question

Assertion :The "biological species" concept helps us to ask how species are formed. Reason: The concept of biological species focusses our attention on the question of how reproductive isolation comes about.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Both Assertion and Reason are incorrect.

Answer 1

The correct option is D Both Assertion and Reason are incorrect.

The biological species concept defines organisms belonging or not belonging to the same species based on whether they can interbreed to make fertile offspring.

Reproductive isolation comes due to environmental conditions, genetic drift or natural selection. It has nothing to do with the concept of biological species.

Both the development of reproductive isolation and the differentiation of other characters identifying organisms as members of a species is influenced by selection or by genetic drift. In selection, adaptation to a particular set of environmental conditions drives speciation. In genetic drift, chance events, such as the genetic diversity present in individuals that become geographically isolated, leads to the formation of new species.

So, the correct option is 'Both Assertion and Reason are incorrect'.