Sarah and John are having a discussion on genetic diversity Sarah believes it happens over a long period of time John believes it happens immediately who is correct

Genetic diversity occurs through natural selection and the process of natural selection is a evolutionary process which occurs with time and ages through the generations.

While genetic variation is caused by mutation, random fertilization and recombination. This usually occurs during cell division and reproduction or any infection.

Thus Genetic diversity is a long process while the genetic variation is an immediate process of producing variation in the genes.