Gene flow also called
migration is any movement of individuals, and/or the genetic material they carry, from one population to
another. Gene flow includes lots of different kinds of events, such
as pollen being blown to a new destination or people moving to new
cities or countries. If gene versions are carried to a population where those gene versions previously did not exist,
gene flow can be a very important source
of genetic variation. In the
graphic below, the gene version for brown coloration moves from one population to another.