Geenivoolust

Geenivoolust is a population-genetic process in which alleles move among subpopulations or demes due to the dispersal of individuals or gametes, followed by reproduction. This gene exchange changes allele frequencies in both donor and recipient groups and tends to homogenize genetic differences between populations.

Gene flow occurs through several mechanisms, including the movement of individuals between populations, seed or pollen dispersal in plants, and the transfer of genetic material via other reproductive vectors. The rate of gene flow depends on how many migrants occur per generation and on the structure of the populations involved. Geographic barriers, habitat fragmentation, and differences in mating or dispersal behavior can limit gene flow, while connected or mobile populations facilitate it.

The consequences of geenivoolust are context-dependent. In general, gene flow reduces genetic differentiation among populations, increasing genetic similarity (often measured by lower FST values) and raising genetic diversity within populations. It can introduce new alleles that enhance adaptability to changing environments, but it can also dilute locally advantageous alleles, potentially hindering local adaptation. The overall effect depends on the balance between migration, selection, drift, and mutation.

In research and conservation, gene flow is a key factor in managing population connectivity. It is estimated using parameters such as the number of migrants per generation and genetic differentiation metrics, with demographic and ecological data informing its role in shaping population structure. Real-world examples appear across animals, plants, and humans, where migration and dispersal influence genetic variation over space and time.