Which term describes the movement of genes from one population to another?

• A. Movement of genes between populations
• B. Movement of individuals between populations
• C. Random changes in allele frequencies
• D. Creation of new genes

Answer: (A)

Gene flow describes the movement of genes between populations. It happens when individuals migrate to a new population and breed there, or when their gametes (like pollen) move between populations and introduce alleles into the other gene pools. This transfer changes the allele frequencies in the populations involved and tends to make populations more genetically similar over time. It’s different from simply moving individuals (which is migration rather than the gene transfer itself), from genetic drift (random changes in allele frequencies), and from mutation (the creation of new genes). An example is pollen blown to a neighboring population, bringing new alleles into that population’s gene pool.