How does the creation of variations in a species promotes survival

Dear student,Variation is the basis for evolution and genetic diversity. Variation helps species to get well adapted to the existing environment. New species emerges because of variation. When the environment changes radically, the few who are able to withstand those changes will be the ones who define the population in the future. It also helps a species to emerge strong if favoured by natural selection. Variation helps a species to be resistant to diseases, thus if a species is to survive there has to be variation.Regards