What term describes the movement of alleles caused by individuals immigrating into or emigrating out of a population?

The term that describes the movement of alleles due to individuals immigrating into or emigrating out of a population is gene flow. Gene flow occurs when members of different populations interbreed, leading to a transfer of genetic material. This process can introduce new alleles into a population or alter allele frequencies, thereby affecting genetic diversity and evolutionary dynamics.

Gene flow is crucial for maintaining genetic variation within populations, as it counters the effects of genetic drift and separation due to environmental factors. It can also play a role in adaptation by providing new genetic combinations that may be beneficial in changing environments. Understanding gene flow is essential in the context of evolution, conservation biology, and studies on population genetics.