Organisms change over time. Some of these changes make no difference to the success or failure of the organisms that inherit them; other changes do. Take a group of antelopes in which one individual has longer legs than its siblings. Those longer legs make the individual better at escaping from predators, hence giving it an advantage in the survival stakes. Its descendants inherit this feature and are better able to survive as a consequence. Those longer legs have thus become an 'adaptation'. Their evolution means that this particular lineage of antelopes has adapted to its conditions, thanks to its development of this feature.
Over the generations, the individual components of the genetic code within a species change, or mutate. So far as we know, mutations may provide no evolutionary advantage at all. They may be disadvantageous, in which case they are weeded out via natural selection; or they may be advantageous, in which case they persist through the generations.
Choose an appropriate title for the passage from the following options:-
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Adaptation and Mutation
The passage has two parts: the first explains how a useful feature, the antelope's longer legs, becomes an adaptation; the second explains mutation, the change in the genetic code, and what happens to harmful and useful mutations. A title that names both ideas covers the whole passage.
Why the Other Options are Incorrect?
Option 2: Mutation: A Necessity — Incorrect. Overstated: the passage says that many mutations give no advantage and some are harmful, so it does not present mutation as a necessity.
Option 3: Genetic Code — Incorrect. Too narrow: the genetic code is mentioned only to explain mutation; the title leaves out adaptation.
Option 4: Survival of the Antelope — Incorrect. Too narrow: the antelope is only an example used to explain adaptation.