Genetic isolate

A genetic isolate is a population that has little to no genetic mixing with other populations of the same species, whether because of geographic barriers or restrictions on breeding, and such isolated populations can eventually diverge into new species. Isolation can arise from physical separation that prevents interbreeding, from human activities such as deforestation that fragment habitat and reduce gene flow, from simple distance, which reduces genetic exchange the farther populations are apart, or from behavioral or ecological differences that reduce breeding between groups. How genetically distinct an isolated population becomes over time depends on the interplay of genetic drift, gene flow and natural selection. Natural examples include island populations and species living at the edges of their range; human-created examples include restricted dog breeding programs and island communities such as Tristan da Cunha and the Pitcairn Islands, while populations such as Sardinians and Finns show a reduced, though not complete, degree of genetic isolation.