How does genetic variation affect the type of traits or the adaptations in the individuals of a species?

Genetic variation describes the genetic differences among individuals of the same species that are naturally occurring.  Each genotype within a population usually has different degrees of fitness to an environment. Mating between same species with favored genes guarantees survival of the population in their chosen environment. As the environment changes, the mating behavior between species may again change resulting to a different gene pool to guarantee survival.