Question

Consider an imaginary group of organisms, and make up a scenario in which both gene flow and genetic drift occur. Make sure that both concepts are clearly defined, and completely and specifically illustrated in your answer. If using diagrams or graphs to help explain the situation, be sure they include informative labels that make what you are depicting easy to understand.

Answer 1

Genetic drift occurs when the allele frequency changes as a result of the decreased population size due to effects such as bottleneck effect or founder's effect. Gene flow happens when the alleles of one population are transferred to another population as a result of migration or geographical isolation.

Consider a population of beetles living in one area. If this population undergoes the bottleneck effect, then a random group of alleles will survive and continue in the population (genetic drift). If some members of the same population migrate to another population living in an adjacent area, then the allele frequency of the second population will be altered too (gene flow).