(N/A) Migration, also known as gene flow, involves the movement of individuals from one population to another.
When individuals migrate, they carry their alleles with them, which alters the gene frequencies in both the source and the recipient populations.
If the migrating individuals possess traits that are favored by the environment in the new location, migration can enhance the effects of natural selection by increasing the frequency of beneficial alleles.
Conversely, if the migrating individuals introduce alleles that are less fit or counteract the current selective pressures, migration can blur or mask the effects of selection by introducing genetic variation that opposes the adaptive trend.
Over time, repeated gene flow can prevent populations from diverging or, if the change is significant enough, it may contribute to speciation.