The importance of gene variations in evolution

In order to understand why option 'C' is the correct answer, we need to delve into the role of gene variations in the process of evolution. Gene variations, also known as genetic variations, are essential for the occurrence of evolution. These variations arise due to changes or mutations in the genetic material of an organism. They can occur in either somatic cells or germ cells.

Somatic variations vs Germinal variations

- Somatic variations: Somatic variations refer to changes in the genetic material of the somatic cells, which are non-reproductive cells. These variations cannot be passed on to the next generation as they are not present in the germ cells (sperm and egg cells) that give rise to offspring. Somatic variations can occur due to environmental factors, such as exposure to radiation or chemicals, but they do not contribute to evolution.

- Germinal variations: Germinal variations, on the other hand, occur in the germ cells and can be passed on to the next generation. These variations are essential for the occurrence of evolution as they form the basis for genetic diversity within a population. Genetic diversity is crucial because it allows populations to adapt to changing environments and increases the chances of survival and reproduction.

The role of gene variations in evolution

- Genetic variation: Gene variations are the raw material for natural selection, the driving force of evolution. They create differences in traits among individuals within a population. Some variations may be beneficial, providing individuals with an advantage in a particular environment, while others may be detrimental or have no effect.

- Natural selection: Natural selection acts on these variations by favoring individuals with advantageous traits. These individuals are more likely to survive, reproduce, and pass on their beneficial variations to the next generation. Over time, this leads to a gradual change in the frequency of certain traits within a population, ultimately resulting in the evolution of new species or adaptations to different environments.

The significance of gene variations in the given options

- Option 'A': The inheritance of acquired characters refers to the now-discredited idea that organisms can pass on characteristics acquired during their lifetime to their offspring. While this concept was proposed by Jean-Baptiste Lamarck, it does not play a significant role in modern evolutionary theory. Therefore, its absence would not prevent evolution from occurring.

- Option 'B': Somatic variations, as mentioned earlier, are not inheritable and do not contribute to genetic diversity in a population. Although they may occur, they do not play a direct role in the process of evolution.

- Option 'C': Gene variations must be found among members of a population for evolution to take place. Without gene variations, there would be no genetic diversity, and natural selection would have nothing to act upon. Therefore, the absence of gene variations among individuals would indeed prevent evolution from occurring.

- Option 'D': Somatic variations transforming into germinal variations is not a necessary condition for evolution. While germinal variations are essential for genetic diversity, they can arise independently through various mechanisms such as mutation, recombination, and gene flow.

In conclusion, the correct answer, option 'C', states that there would be no evolution if gene variations were not found among members of a population. Genetic diversity is crucial for natural selection to occur and drive the process of evolution.