Human migration

Human migration denotes any movement by humans from one locality to another, often over long distances or in large groups. Humans are known to have migrated extensively throughout history and prehistory. Migration and population isolation is one of the four evolutionary forces (along with natural selection, genetic drift, and mutation). The study of the distribution of and change in allele (gene variations) frequencies under such influences is the discipline of Population genetics.The movement of populations in modern times has continued under the form of both voluntary migration within one's region, country, or beyond, and involuntary migration (which includes slave trade, Trafficking in human beings and ethnic cleansing). The people who migrate are called migrants, or, more specifically, emigrants, immigrants or settlers, depending on historical setting, circumstance and perspective.
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