Short Answer

Variation helps in evolution by creating differences among individuals of the same species. These differences allow some organisms to survive better than others in changing environments. Without variation, all individuals would be the same and respond in the same way to environmental changes.

When useful variations help organisms survive and reproduce, these traits are passed to the next generation. Over a long period of time, such changes lead to evolution and the formation of new species.

Detailed Explanation :

Role of Variation in Evolution

Variation plays a very important role in evolution. Evolution means the gradual change in living organisms over many generations. This change is possible only when differences exist among individuals of the same population. These differences are called variations. Without variation, evolution cannot occur because there would be no traits for natural selection to act upon.

In any population, individuals are not exactly the same. They differ in size, shape, color, strength, behavior, and many other features. These differences may seem small, but they are very important for survival. When the environment changes, some variations prove to be useful while others may not.

Variation Creates Survival Advantage

Variation helps some individuals survive better than others. In nature, organisms face many challenges such as lack of food, predators, diseases, and climate changes. Individuals with useful variations are better able to face these challenges.

For example, in a population of animals, some may be faster runners. When predators attack, faster animals can escape more easily. Similarly, plants with deeper roots can survive drought better than plants with shallow roots. These useful variations give certain individuals a survival advantage.

Variation and Natural Selection

Natural selection is closely linked to variation. Natural selection means that nature selects organisms that are best suited to their environment. This selection is possible only because of variation.

When individuals with helpful variations survive and reproduce, they pass these traits to their offspring. Individuals without helpful variations may fail to survive or reproduce. Over time, useful variations become more common in the population. This process leads to gradual change, which is evolution.

Variation Helps in Adaptation

Adaptation means developing features that help organisms survive in their environment. Variation is the starting point of adaptation. Different individuals show different traits, and some of these traits help them live better in a particular environment.

For example, animals living in cold regions may have variations that result in thicker fur. Plants growing in deserts may have variations that help them store water. Over many generations, these useful variations lead to strong adaptations. Thus, variation helps organisms adjust to their surroundings.

Variation Increases Chances of Survival

Variation increases the chances that at least some individuals of a species will survive environmental changes. If all individuals were identical, a single disease or environmental change could wipe out the entire population.

With variation, some individuals may be resistant to diseases, while others may tolerate extreme temperatures. These individuals survive and continue the species. Therefore, variation protects species from extinction and helps maintain life.

Variation Leads to Evolutionary Change

Evolution is a slow and gradual process. Small variations accumulate over many generations. Each generation may show slight improvements or changes compared to the previous one.

As useful variations are passed on repeatedly, the population slowly changes its characteristics. Over a very long period of time, these changes may become so great that a new species is formed. Thus, variation leads directly to evolutionary change.

Variation and Formation of New Species

When populations of the same species live in different environments, they develop different variations. These variations help them survive in their specific surroundings. Over time, the populations become very different from each other.

Eventually, they may no longer be able to interbreed. When this happens, new species are formed. This process is called speciation, and it occurs due to accumulation of variations over time.

Variation Is the Basis of Evolution

Variation is the foundation of evolution. It provides the raw material on which natural selection works. Without variation, all individuals would be the same, and there would be no survival advantage for any organism.

Because variation exists, nature can select the best-suited individuals. This leads to adaptation, survival, and evolution. Therefore, variation is essential for the continuity and diversity of life on Earth.

Conclusion

Variation helps in evolution by creating differences among individuals of the same species. These differences allow some organisms to survive better, adapt to their environment, and reproduce successfully. Over many generations, useful variations accumulate and lead to evolutionary changes. Without variation, natural selection and evolution would not be possible.