When thinking about how some populations became lighter or darker over time, we are describing evolutionary changes in populations thousands of years ago prior to the development of modern technology. The host of Ologies, Ali Ward, asked Dr. Lasisi about how transportation options like cars, high speed rail, and planes that have made global movement easier than ever may affect evolution. Because of easier transportation options, many people are migrating to areas where their most recent ancestors did not live. When people move to new areas that aren't representative of their ancestry, assuming they reproduce, what mechanism of evolution does this movement represent? Mutation Genetic Drift Gene Flow Natural Selection