What environmental factor would cause an increase in the rate of genetic change?

Answer 1

climate, food supply, and even something like radiation exposure would increase the rate of genetic change. As Darwin argued, it is the survival of the fittest. Much like the Peppered Moths, those animals who can change to live in their environment will survive to pass on their dna. If something (like radiation) prompts a genetic mutation (or if it is sponatenous) and that trait is better for the environment it will most likely become a more prevalent trait in a species,

Answer 2

Almost any enviromental factor could or would cause such an increase. If not in humans, then in other organisms.