How does the creation of variations in a species promote survival?

Q. How does the creation of variations in a species promote survival? 

 

Answer:- 

All the variations in the species do not have equal chances of survival in the environment. The survival of the variations depends upon the nature of variation. Different individuals have different chances. Selection of variants by environmental factors forms the basis for evolutionary processes.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