Selection of variants by environmental factors forms the basis for evolutionary processes.explain the statement with example.

CBSE Class 10 Answered

Selection of variants by environmental factors forms the basis for evolutionary processes.explain the statement with example.

Asked by Tejasvikumar12438 | 07 Mar, 2019, 09:00: PM

Expert Answer

Variations produced in the organisms get accumulated and are passed on from the parents to their offspring by the phenomenon of inheritance.
The significance of a variation shows up only if it continues to be inherited by the offspring of several generations.
All variations that occur in a species do not have an equal chance of surviving in the environment. Depending on the nature of variations, different individuals would have different kinds of advantages.
Selection of variants by the environmental factors forms the basis of evolutionary processes.
Useful variations stand a chance of survival because nature selects only the useful variations.
These variations may lead to increased survival advantages of the individuals due to positive adoption of traits or may merely contribute to the genetic drift.
For example, bacteria variants which can withstand heat have better chances to survive in a heat wave than the non-variant bacteria having no capacity to tolerate heat wave. Thus, variants in a population of a species help in the survival of a species.
In the absence of variation, there would be no science of heredity as all individuals of a race would be identical to one another in all aspects.

Answered by Sheetal Kolte | 08 Mar, 2019, 02:59: PM