Can Gene Flow Prevent or Speed up Evolution

The effect of gene flow is to reduce genetic differences between populations, thereby preventing or delaying the evolution of the populations in different geographical areas into separate species of the pathogen.

How does gene flow prevent evolution?

For this reason, gene flow has been thought to constrain speciation and prevent range expansion by combining the gene pools of the groups, thus preventing the development of differences in genetic variation that would have led to differentiation and adaption.

What happens when gene flow increases?

The introduction of new alleles through gene flow increases variability within the population and makes possible new combinations of traits. In humans gene flow usually comes about through the actual migration of human populations, either voluntary or forced.