Genetic diversity is the range genetic characteristics within a single species.The most important level in term of evolution is that of the gene.
genetic diversity is important to the survival of a species
Genetic diversity is important because it codes variations of phenotypes, some of which may better suit the individual organism to a particular environment than others, giving it an increased chance of survival. If this individual survives, there is an increased chance of it reproducing to pass the advantageous gene to its offspring, also giving them an increased chance of surviving. This genetic advantage will increase the survival of the species within that environment.